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  • Wiley  (36)
  • Springer  (34)
  • Massachusetts Institute of Technology and Woods Hole Oceanographic Institution  (28)
  • Essen : Verl. Glückauf
  • Krefeld : Geologischer Dienst Nordhein-Westfalen
  • 2020-2023  (98)
  • 2005-2009
  • 2021  (98)
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  • 1
    Publication Date: 2022-01-19
    Description: Global population projections foresee the biggest increase to occur in Africa with most of the available uncultivated land to ensure food security remaining on the continent. Simultaneously, greenhouse gas emissions are expected to rise due to ongoing land use change, industrialisation, and transport amongst other reasons with Africa becoming a major emitter of greenhouse gases globally. However, distinct knowledge on greenhouse gas emissions sources and sinks as well as their variability remains largely unknown caused by its vast size and diversity and an according lack of observations across the continent. Thus, an environmental research infrastructure—as being setup in other regions—is more needed than ever. Here, we present the results of a design study that developed a blueprint for establishing such an environmental research infrastructure in Africa. The blueprint comprises an inventory of already existing observations, the spatial disaggregation of locations that will enable to reduce the uncertainty in climate forcing’s in Africa and globally as well as an overall estimated cost for such an endeavour of about 550 M€ over the next 30 years. We further highlight the importance of the development of an e-infrastructure, the necessity for capacity development and the inclusion of all stakeholders to ensure African ownership.
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  • 2
    Publication Date: 2022-01-07
    Description: The present study aims to valorize the apple peels (AP) and grape seeds (GS) by the fortification of the yogurts using their powder. Firstly, the optimization of the extraction parameters for assessing maximum of total phenolic content (TPC) was achieved. Under the optimized conditions, the experimental maximum yields of TPC were 19.33 ± 2.33 and 240.59 ± 4.77 mg Gallic Acid Equivalents (GAE)/100 g Dry Weight (DW) for AP and GS, respectively, which was in close agreement with predicted values (19.32 ± 0.91 and 242.26 ± 11.08 mg GAE/100 g DW for AP and GS, respectively). The antioxidant capacity of GS extract was better with IC50 of 12.22 ± 0.89 and 225.47 ± 7.10 µg/ml in DPPH and phosphomolybdenum assays, respectively. Besides, powder from these by-products was incorporated into yogurt samples. The classification test revealed that the yogurt prepared with GS powder was the preferred one.
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  • 3
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, p. 1.
    Publication Date: 2022-01-14
    Description: Pa.ra.rho.do.spi.ril'lum. Gr. pref. para-, beside, alongside of, near, like; N.L. neut. n. Rhodospirillum, a bacterial generic name; N.L. neut. n. Pararhodospirillum, resembling Rhodospirillum. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Rhodospirillaceae / Pararhodospirillum Pararhodospirillum species are spiral-shaped, mesophilic, and phototrophic freshwater bacteria of the Rhodospirillaceae family. Cells are motile by polar flagella, and photosynthetic pigments are located in internal photosynthetic membranes present as lamellar stacks. Photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series with spirilloxanthin itself lacking. Ubiquinone-9 and rhodoquinone-9 are the major quinones. All species are sensitive to oxygen and require anoxic or microoxic conditions for growth. They grow photoheterotrophically under anoxic conditions in the light. Photoautotrophic growth, aerobic chemotrophic growth, and fermentative growth have not been demonstrated. Growth factors are required. DNA G + C content (mol%): 60.2–65.8 (Bd and HPLC) and 64.7–67 (GA). Type species: Pararhodospirillum photometricum Lakshmi et al. 2014VP (basonym: Rhodospirillum photometricum Molisch 1907AL).
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  • 4
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, p. 1.
    Publication Date: 2022-01-14
    Description: Rho.do.ci'sta Gr. neut. n. rhodon, rose; L. fem. n. cista a basket; N.L. fem. n. Rhodocista, red basket. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Azospirillaceae / Rhodocista Rhodocista centenaria is a well-characterized thermotolerant, phototrophic purple bacterium growing optimally at a temperature of 40–45°C and a maximal growth temperature of 48°C. Under low nutrient conditions, Rhodocista forms desiccation-, heat-, and UV-resistant cysts, which enable survival under severe drought and salt stress. Cells are motile by a single polar flagellum in liquid culture but in addition form lateral flagella on agar surfaces and under these conditions may show a characteristic phototactic movement. Rhodocista species grow under photoheterotrophic conditions and also are able to perform a chemotrophic aerobic metabolism. They encode enzymes for autotrophic carbon dioxide fixation and fixation of dinitrogen, although autotrophic growth has so far not been demonstrated. In the type species, bacteriochlorophyll biosynthesis occurs under both aerobic and anaerobic growth conditions. Aerobically grown cells are fully pigmented. In other species, oxygen may inhibit photosynthetic pigment biosynthesis, and aerobically grown cells are colorless. DNA G + C content (mol%): 68.8–69.9 (Tm), 70.5 (WGS). Type species: Rhodocista (Rcs.) centenaria Kawasaki et al. 1992, VL48 (basonym: Rhodospirillum centenum Favinger et al. 1989, VL48).
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  • 5
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, p. 1.
    Publication Date: 2022-01-14
    Description: Rho.do.pi'la. Gr. neut. n. rhodon the rose; N.L. fem. n. pila a ball or sphere; N.L. fem. n. Rhodopila red sphere. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Acetobacteraceae / Rhodopila Rhodopila globiformis is one of the very few anaerobic phototrophic purple bacteria that can grow below pH 6 with an optimum depending on the organic carbon substrate from 4.8 to 5.6. Growth occurs preferably photoheterotrophically under anoxic conditions in the light. Cells are sensitive to oxygen but grow by respiration under microoxic conditions in the dark. Growth factors are required. They are acidophilic freshwater bacteria that inhabit acidic warm sulfur springs. Cells are spherical to ovoid, motile by means of polar flagella, and divide by binary fission. They stain Gram-negative and have internal photosynthetic membranes of the vesicular type. Rhodopila is classified within the Acetobacteraceae family and Rhodospirillales order of the Alphaproteobacteria. The photosynthetic pigments are bacteriochlorophyll a and carotenoids. The major fatty acids are C18:1 (∼75%) and C16:0. Ubiquinones, menaquinones, and rhodoquinones with 9 and 10 isoprene units are produced. DNA G + C content (mol%): 67.1 (genome analysis). Type species: Rhodopila globiformis Imhoff et al. 1984VP (basonym: Rhodopseudomonas globiformis Pfennig 1974AL).
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  • 6
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, p. 1.
    Publication Date: 2022-01-14
    Description: Rho.do.pla'nes. Gr. neut. n. rhodon rose; Gr. masc. n. planos a wanderer; N.L. masc. n. Rhodoplanes a red wanderer. Proteobacteria / Alphaproteobacteria / Rhizobiales / Hyphomicrobiaceae / Rhodoplanes The genus Rhodoplanes accommodates species of anoxygenic facultative phototrophic bacteria that grow optimally under anaerobic conditions in the light. They belong to the family Hyphomicrobiaceae of the order Rhizobiales within the class Alphaproteobacteria. Cells are Gram-stain-negative rods and multiply by budding and asymmetric cell division. Motile by means of polar, subpolar, or lateral flagella. Internal photosynthetic membranes are present as lamellar stacks parallel to the cytoplasmic membrane. Photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series. Photoorganotrophy with pyruvate and some other organic acids is the best mode of growth. Straight-chain, monounsaturated C18:1 ω7c is the main component of the cellular fatty acids and C16:0 is a second major component. Ubiquinones and rhodoquinones with 10 isoprene units (Q-10 and RQ-10) are present. The main components of polar lipids are phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, and diphosphatidylglycerol. Terrestrial and freshwater bacteria having a preference for mesophilic to moderately thermophilic habitats and neutral pH. DNA G + C content (mol%): 67.2–70.4. Type species: Rhodoplanes roseus Hiraishi and Ueda 1994 (Rhodopseudomonas rosea Janssen and Harfoot 1991).
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  • 7
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, pp. 1-7.
    Publication Date: 2022-01-17
    Description: Rho.do.pi'la. Gr. neut. n. rhodon the rose; N.L. fem. n. pila a ball or sphere; N.L. fem. n. Rhodopila red sphere. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Acetobacteraceae / Rhodopila Rhodopila globiformis is one of the very few anaerobic phototrophic purple bacteria that can grow below pH 6 with an optimum depending on the organic carbon substrate from 4.8 to 5.6. Growth occurs preferably photoheterotrophically under anoxic conditions in the light. Cells are sensitive to oxygen but grow by respiration under microoxic conditions in the dark. Growth factors are required. They are acidophilic freshwater bacteria that inhabit acidic warm sulfur springs. Cells are spherical to ovoid, motile by means of polar flagella, and divide by binary fission. They stain Gram-negative and have internal photosynthetic membranes of the vesicular type. Rhodopila is classified within the Acetobacteraceae family and Rhodospirillales order of the Alphaproteobacteria. The photosynthetic pigments are bacteriochlorophyll a and carotenoids. The major fatty acids are C18:1 (∼75%) and C16:0. Ubiquinones, menaquinones, and rhodoquinones with 9 and 10 isoprene units are produced. DNA G + C content (mol%): 67.1 (genome analysis). Type species: Rhodopila globiformis Imhoff et al. 1984VP (basonym: Rhodopseudomonas globiformis Pfennig 1974AL).
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  • 8
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, pp. 1-10.
    Publication Date: 2022-01-17
    Description: Rho.do.spi.ril'lum. Gr. neut. n. rhodon, the rose; N.L. neut. n. Spirillum, a bacterial genus; N.L. neut. n. Rhodospirillum, the rose Spirillum. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Rhodospirillaceae / Rhodospirillum The genus Rhodospirillum has harbored a diverse set of spiral-shaped phototrophic bacteria, most of which have been reclassified as species of other genera, families, and even orders and phyla since the 1980s. The heterogeneity has been long known, but only the faith into sequence-based information gave strong support for taxonomic rearrangements. Currently, the genus Rhodospirillum contains a single species, which is characterized by spiral-shaped cells, motility by bipolar flagella, and internal membranes as vesicles. It performs anaerobic photosynthesis, which is restricted to anoxic light conditions due to the oxygen-sensitive biosynthesis of bacteriochlorophyll and thus the phototrophic apparatus. It can grow photoheterotrophically as well as photoautotrophically. The key enzyme of autotrophic carbon dioxide fixation in Rhodospirillum rubrum, ribulose bisphosphate carboxylase (RubisCO) type-II, is well characterized and forms a homodimer that is also encoded in some related genera of Rhodospirillaceae. Chemotrophic growth may also occur under microoxic to oxic conditions in the dark and anaerobically by fermentation. The genus comprises mesophilic freshwater bacteria. Ubiquinones and rhodoquinones with 10 isoprene units and fatty acids typical of other Alphaproteobacteria with C18:1, C16:0, and C16:1 as major components are present. DNA G + C content (mol%): 64.6–65.7, type 65.4 (genome analysis), 63.8–65.8 (Bd). Type species: Rhodospirillum (Rsp.) rubrum Molisch 1907AL (basonym: Spirillum rubrum Esmarch 1887).
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  • 9
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, pp. 1-8.
    Publication Date: 2022-01-17
    Description: Rho.do.ci'sta Gr. neut. n. rhodon, rose; L. fem. n. cista a basket; N.L. fem. n. Rhodocista, red basket. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Azospirillaceae / Rhodocista Rhodocista centenaria is a well-characterized thermotolerant, phototrophic purple bacterium growing optimally at a temperature of 40–45°C and a maximal growth temperature of 48°C. Under low nutrient conditions, Rhodocista forms desiccation-, heat-, and UV-resistant cysts, which enable survival under severe drought and salt stress. Cells are motile by a single polar flagellum in liquid culture but in addition form lateral flagella on agar surfaces and under these conditions may show a characteristic phototactic movement. Rhodocista species grow under photoheterotrophic conditions and also are able to perform a chemotrophic aerobic metabolism. They encode enzymes for autotrophic carbon dioxide fixation and fixation of dinitrogen, although autotrophic growth has so far not been demonstrated. In the type species, bacteriochlorophyll biosynthesis occurs under both aerobic and anaerobic growth conditions. Aerobically grown cells are fully pigmented. In other species, oxygen may inhibit photosynthetic pigment biosynthesis, and aerobically grown cells are colorless. DNA G + C content (mol%): 68.8–69.9 (Tm), 70.5 (WGS). Type species: Rhodocista (Rcs.) centenaria Kawasaki et al. 1992, VL48 (basonym: Rhodospirillum centenum Favinger et al. 1989, VL48).
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  • 10
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, pp. 1-2.
    Publication Date: 2022-01-17
    Description: Rho.do.tha.las.si.a.ce'ae. N.L. neut. n. Rhodothalassium, type genus of the family; suff. -aceae, ending to denote a family; N.L. fem. pl. n. Rhodothalassiaceae, the family of Rhodothalassium. Proteobacteria / Alphaproteobacteria / Rhodothalassiales / Rhodothalassiaceae Cells are vibrioid to spiral shaped, are motile by means of polar flagella, and multiply by binary fission. They belong to the class Alphaproteobacteria and stain Gram-negative. An unusual protein-rich cell wall with only low amounts of peptidoglycan may be present. Internal photosynthetic membranes are present as lamellar stacks lying parallel to the cytoplasmic membrane. The photosynthetic pigments are bacteriochlorophyll a and carotenoids. The major ubiquinone and menaquinone components are Q-10 and MK-10. Growth occurs preferably photoheterotrophically under anoxic conditions in the light but also may be possible under microoxic to oxic conditions in the dark. Obligately halophilic bacteria that require NaCl or sea salt for growth. Habitats are anoxic zones of hypersaline environments such as salterns, salt lakes, and evaporated coastal lagoons that are exposed to light. At present, the family includes a single genus. DNA G + C content of the type species and genus (mol%): 68.5–69.0 (genome analysis), 60.0–62.8 (HPLC analysis). Type genus: Rhodothalassium Imhoff et al. 1998VP.
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  • 11
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, p. 1.
    Publication Date: 2022-01-17
    Description: Phae.o.spi.ril'lum. Gr. masc. adj. phaeos, brown; N.L. neut. n. Spirillum, a bacterial genus; N.L. neut. n. Phaeospirillum, brown Spirillum. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Rhodospirillaceae / Phaeospirillum Phaeospirillum species are vibrioid to spiral shaped and motile Alphaproteobacteria. They are strictly anaerobic and anoxygenic phototrophic bacteria with a reaction center and light-harvesting complexes located in the internal membrane stacks formed at a sharp angle with the cytoplasmic membrane. The photosynthetic pigments are bacteriochlorophyll a esterified with phytol and carotenoids of the spirilloxanthin series, with spirilloxanthin itself lacking. They have a photoheterotrophic metabolism and depend on anoxic conditions for biosynthesis of bacteriochlorophyll and photosynthesis. The preferred carbon substrates are fatty acids including longer chains up to pelargonate. The longer chain fatty acids provide a selective advantage for several of the species. Chemotrophic growth may be possible at controlled and very low oxygen tensions (〈1.5 kPa) in the dark. Ammonia and dinitrogen serve as nitrogen sources. Assimilatory sulfate reduction is present. Growth factors may be required. Phaeospirillum species are mesophilic freshwater bacteria with a preference for neutral pH that live in stagnant and anoxic freshwater habitats. DNA G + C content (mol%): 60.5–65.3 (Bd), 62.1–62.8 (Tm), 61.5–64.7 (WGS). Type species: Phaeospirillum (Phs.) fulvum Imhoff et al. 1998VP (basonym: Rhodospirillum fulvum van Niel 1944AL).
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  • 12
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, p. 1.
    Publication Date: 2022-01-17
    Description: Rho.do.tha.las.si.a'les. N.L. neut. n. Rhodothalassium, type genus of the order; suff. -ales, ending denoting an order; N.L. fem. pl. n. Rhodothalassiales, the Rhodothalassium order. Proteobacteria / Alphaproteobacteria / Rhodothalassiales The order currently comprises a single family and genus, which is characterized by halophilic anoxygenic phototrophic bacteria having spiral-shaped cells and containing lamellar photosynthetic membranes. The properties of the order are determined by the characteristics of the Rhodothalassiaceae family.
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  • 13
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, p. 1.
    Publication Date: 2022-01-17
    Description: Rho.do.tha.las'si.um. Gr. neut. n. rhodon, the rose; Gr. masc. adj. thalassios, belonging to the sea; N.L. neut. n. Rhodothalassium, the rose belonging to the sea. Proteobacteria / Alphaproteobacteria / Rhodothalassiales / Rhodothalassiaceae / Rhodothalassium The genus Rhodothalassium is represented by a single species and is the only genus of the Rhodothalassiaceae family and Rhodothalassiales order. It is characterized by vibrioid- to spiral-shaped cells which multiply by binary fission and are motile by means of flagella. Internal photosynthetic membranes are present as lamellar stacks lying parallel to the cytoplasmic membrane. Photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series. Ubiquinones and menaquinones with 10 isoprene units (Q-10 and MK-10) are present. Growth occurs preferably photoheterotrophically under anoxic conditions in the light. Most strains also grow chemoorganotrophically under oxic conditions in the dark. Rhodothalassium species are obligately halophilic, require NaCl or sea salt for growth, and live in anoxic zones of hypersaline environments such as salterns, salt lakes, and evaporated coastal lagoons that are exposed to the light. DNA G + C content (mol%): 68.5–69.0 (WGS), 60.0–62.8 (HPLC). Type species: Rhodothalassium salexigens Imhoff et al. 1998VP (basonym: Rhodospirillum salexigens Drews 1981, VL9).
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  • 14
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, pp. 1-12.
    Publication Date: 2022-01-17
    Description: Rho.do.pla'nes. Gr. neut. n. rhodon rose; Gr. masc. n. planos a wanderer; N.L. masc. n. Rhodoplanes a red wanderer. Proteobacteria / Alphaproteobacteria / Rhizobiales / Hyphomicrobiaceae / Rhodoplanes The genus Rhodoplanes accommodates species of anoxygenic facultative phototrophic bacteria that grow optimally under anaerobic conditions in the light. They belong to the family Hyphomicrobiaceae of the order Rhizobiales within the class Alphaproteobacteria. Cells are Gram-stain-negative rods and multiply by budding and asymmetric cell division. Motile by means of polar, subpolar, or lateral flagella. Internal photosynthetic membranes are present as lamellar stacks parallel to the cytoplasmic membrane. Photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series. Photoorganotrophy with pyruvate and some other organic acids is the best mode of growth. Straight-chain, monounsaturated C18:1 ω7c is the main component of the cellular fatty acids and C16:0 is a second major component. Ubiquinones and rhodoquinones with 10 isoprene units (Q-10 and RQ-10) are present. The main components of polar lipids are phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, and diphosphatidylglycerol. Terrestrial and freshwater bacteria having a preference for mesophilic to moderately thermophilic habitats and neutral pH. DNA G + C content (mol%): 67.2–70.4. Type species: Rhodoplanes roseus Hiraishi and Ueda 1994 (Rhodopseudomonas rosea Janssen and Harfoot 1991).
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  • 15
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, pp. 1-7.
    Publication Date: 2022-01-17
    Description: Pa.ra.rho.do.spi.ril'lum. Gr. pref. para-, beside, alongside of, near, like; N.L. neut. n. Rhodospirillum, a bacterial generic name; N.L. neut. n. Pararhodospirillum, resembling Rhodospirillum. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Rhodospirillaceae / Pararhodospirillum Pararhodospirillum species are spiral-shaped, mesophilic, and phototrophic freshwater bacteria of the Rhodospirillaceae family. Cells are motile by polar flagella, and photosynthetic pigments are located in internal photosynthetic membranes present as lamellar stacks. Photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series with spirilloxanthin itself lacking. Ubiquinone-9 and rhodoquinone-9 are the major quinones. All species are sensitive to oxygen and require anoxic or microoxic conditions for growth. They grow photoheterotrophically under anoxic conditions in the light. Photoautotrophic growth, aerobic chemotrophic growth, and fermentative growth have not been demonstrated. Growth factors are required. DNA G + C content (mol%): 60.2–65.8 (Bd and HPLC) and 64.7–67 (GA). Type species: Pararhodospirillum photometricum Lakshmi et al. 2014VP (basonym: Rhodospirillum photometricum Molisch 1907AL).
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  • 16
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    Wiley
    In:  In: Bergey's Manual of Systematics of Archaea and Bacteria. Wiley, Chichester, p. 1.
    Publication Date: 2022-01-17
    Description: Ro.se.o.spi'ra. L. masc. adj. roseus, rosy; Gr. fem. n. spira, the spiral; N.L. fem. n. Roseospira the rosy spiral. Proteobacteria / Alphaproteobacteria / Rhodospirillales / Rhodospirillaceae / Roseospira Roseospira species are vibrioid to spiral shaped, anoxygenic, and phototrophic bacteria of the Rhodospirillaceae family that live in various types of marine and slightly saline habitats all over the world. The photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series, and internal photosynthetic membranes are present as vesicles. They perform a phototrophic way of life using organic substrates (photoheterotrophic growth) or inorganic reduced sulfur compounds (photoautotrophic growth) as electron donors for photosynthesis. Bacteriochlorophyll biosynthesis depends on anoxic to microoxic conditions, and chemotrophic growth is possible under microoxic to oxic conditions in the light. Nitrogenase and ribulose bisphosphate carboxylase may be present. Vitamins or yeast extracts are required as growth factors. The G + C content of the DNA is 67.8–71.2 (GA), and the genome size ranges from 4.19 to 4.61 Mb. DNA G + C content (mol%): 67.8–71.2 (GA) (type species 66.6 Tm). Type species: Roseospira mediosalina Imhoff et al. 1998VP (synonym: “Rhodospirillum mediosalinum” Kompantseva and Gorlenko 1984).
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  • 17
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    Springer
    In:  Human-Environment Interactions
    Publication Date: 2022-03-21
    Type: info:eu-repo/semantics/book
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  • 18
    Publication Date: 2022-09-26
    Type: Article , NonPeerReviewed
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  • 19
    Publication Date: 2022-03-02
    Description: To provide a contribution to the Thematic Strategy for Soil Protection, here we present the results of a study focused on the potentially toxic elements (PTE) content in agricultural soils’ representative for the Mediterranean region. To reach this aim, samples of 22 Italian (NE Peloritani Mountains, Sicily) and 18 Turkish (Amik Plain, Hatay) soils were collected and analyzed to evaluate their PTE content. The Italian and Turkish sites have been selected because they represent very important cultivation zones. In Amik Plain (Turkey), the dominant crops consist of cotton, wheat, corn and olives, whereas in NE Peloritani Mountains, Sicily (Italy), an appreciate citrus variety, known as the “Interdonato lemon”, guaranteed by Protected Geographical Indication label, is produced. The collected results include: (1) the assessment of PTE levels in soils; (2) the identifcation of the PTE sources; (3) the relationships between PTE contents and soil properties (pH, electrical conductivity, organic matter, CaCO3, and clay). Several multivariate statistical methods such as correlation matrix, cluster analysis and main component analysis were applied to individuate the anthropogenic vs natural origin of the PTE sources. The detected PTE levels are in decreasing order Mn〉Zn〉V〉Cr〉Cu〉Ni〉As〉Pb〉Co〉Sb〉Se〉Cd for the Italian soils, and Mn〉 Ni〉V〉Zn〉Cr〉Cu〉Pb〉Co〉As〉Se〉Sb〉Cd for the Turkish soils. The overall obtained results allowed to defne: (a) a main lithogenic source for PTE detected in the Italian soils, except for Zn which origin is also associated to anthropogenic input; (b) a lithogenic origin for all of the PTE detected for the Turkish soils, with an associate anthropogenic contribution for Cr, Ni, V, Cu and V. The results obtained in this work enhance the knowledge in the individuation of PTE pollution sources in agricultural soils of the European Mediterranean region.
    Description: Published
    Description: 499
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
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  • 20
    Publication Date: 2022-03-07
    Description: Fjords are recognized as hotspots of organic carbon (OC) burial in the coastal ocean. In fjords with glaciated catchments, glacier discharge carries large amounts of suspended matter. This sedimentary load includes OC from bedrock and terrigenous sources (modern vegetation, peat, soil deposits), which is either buried in the fjord or remineralized during export, acting as a potential source of CO2 to the atmosphere. In sub-Antarctic South Georgia, fjord-terminating glaciers have been retreating during the past decades, likely as a response to changing climate conditions. We determine sources of OC in surface sediments of Cumberland Bay, South Georgia, using lipid biomarkers and the bulk 14C isotopic composition, and quantify OC burial at present and for the time period of documented glacier retreat (between 1958 and 2017). Petrogenic OC is the dominant type of OC in proximity to the present-day calving fronts (60.4 ± 1.4% to 73.8 ± 2.6%) and decreases to 14.0 ± 2.7% outside the fjord, indicating that petrogenic OC is effectively buried in the fjord. Beside of marine OC, terrigenous OC comprises 2.7 ± 0.5% to 7.9 ± 5.9% and is mostly derived from modern plants and Holocene peat and soil deposits that are eroded along the flanks of the fjord, rather than released by the retreating fjord glaciers. We estimate that the retreat of tidewater glaciers between 1958 and 2017 led to an increase in petrogenic carbon accumulation of 22% in Cumberland West Bay and 6.5% in Cumberland East Bay, suggesting that successive glacier retreat does not only release petrogenic OC into the fjord, but also increases the capacity of OC burial.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 21
    Publication Date: 2022-04-22
    Description: Integrated electron microprobe analyses (EMPAs) on glass and Sr–Nd isotope analyses have been performed on 17 tephras from the Middle Pleistocene Mercure lacustrine succession, southern Apennines. Two 40Ar/39Ar ages and the recognition of four relevant tephras from Colli Albani, Sabatini and possibly Roccamonfina volcanoes allowed us to ascribe the investigated succession to the late Marine Isotope Stage (MIS) 15–12 interval (560–440 ka). The Sr–Nd isotopes and major element glass compositions allowed us to attribute 10 out of the other 13 tephras to a poorly known activity of the Roccamofina volcano, whereas two layers were tentatively attributed to previously unknown Middle Pleistocene activity of Ponza Island or Campanian volcanoes, and one to Salina Island. The tephrostratigraphic correlation of the Mercure tephras with the Acerno lacustrine pollen record (Campania) also allowed us to evaluate the climatostratigraphic position of the tephras within the framework of the MIS 15–12 climatic variability. These results were obtained by combining the Sr–Nd isotope ratio with EMPA and 40Ar/39Ar geochronological data. This confirms the notable consistency of this approach for studying the Mediterranean Middle Pleistocene tephrostratigraphy, which, despite its great potential for both volcanology and Quaternary studies, has been hitherto barely explored.
    Description: Published
    Description: 232–248
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: 4V. Processi pre-eruttivi
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: 40Ar/39Ar dating; EMPA glass compositions ; Middle Pleistocene; ; peri-Tyrrhenian explosive volcanisms ; Sr isotopes.
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
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  • 22
    Publication Date: 2022-04-22
    Description: New geochemical and isotopic data on volcanic rocks spanning the period ~75–50 ka BP on Ischia volcano, Italy, shed light on the evolution of the magmatic system before and after the catastrophic, caldera-forming Monte Epomeo Green Tuff (MEGT) eruption. Volcanic ac tivity during this period was influenced by a large, composite and differentiating magmatic system, replenished several times with isotopically distinct magmas of deepprovenance. Chemical and isotopic variations highlight that the pre-MEGT eruptions were fed by trachytic/phonolitic magmas from an isotopically zoned reservoir that were poorly enriched in radiogenic Sr and became progressively less radiogenic with time. Just prior to the MEGT eruption, the magmatic system was recharged by an isotopically distinct magma, relatively more enriched in radiogenic Sr with respect to the previously erupted magmas. This second magma initially fed several SubPlinian explosive eruptions and later supplied the climactic, phonolitic-to-trachytic MEGT eruption(s). Isotopic data, together with erupted volume estimations obtained for MEGT eruption(s), indicate that 〉5–10 km3of this relatively enriched magma had accumulated in the Ischia plumbing system. Geochemical modelling indicates that it accumulated at shallow depths (4–6 km), over a period of ca. 20 ka. After the MEGT eruption, volcanic activity was fed by a new batch of less differentiated (trachyte-latite) magma that was slightly less enriched in radiogenic Sr. The geochemical and Sr–Nd-isotopic variations through time reflect the upward flux of isotopically distinct magma batches, variably contaminated byHercynian crust at 8–12 km depth. The deep-sourced latitic to trachytic magmas stalled at shallow depths (4–6 km depth), differentiated to phonolite through crystal fractionation and assimilation of a feldspar-rich mush, or ascended directly to the surface and erupted.
    Description: Published
    Description: 1035
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: 4V. Processi pre-eruttivi
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Ischia volcano ; Magmatic plumbing system ; Radiogenic isotopes ; Geothermometry ; Feldspar assimilation ; Caldera collapse
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 23
    Publication Date: 2022-04-22
    Description: During the past millennia, several eruptions have occurred within the La Fossa caldera on the island of Vulcano (Aeolian Islands, Italy), some being also described in historical documents dating back to Republican Roman times (first to second century BC). The absolute and relative timing of such activity, however, has remained poorly defined and controversial, due to contrasting ages provided by radiometric and unconventional palaeomagnetic methods. Here, we present a detailed recon- struction of the eruptive history focused on the ninth to fifteenth century AD period that occurred at both La Fossa cone and Vulcanello. This integrated approach involves tephrostratigraphy, standard palaeomagnetic methodology and radiocarbon dating. The new dataset confirms that the lavas exposed above sea level at Vulcanello were erupted between the tenth and eleventh century AD, and not between the first and second century BC as previously suggested. In this same time interval, La Fossa cone was characterized by long-lasting, shoshonitic, explosive activity followed by a discrete, sustained, rhyolitic explosive eruption. Between AD 1050 and 1300, activity was focused only on La Fossa cone, with alternating explosive and effusive eruptions that emplaced four rhyolitic and trachytic lava flows, resulting in significant growth of the cone. After the violent, phreatic event of the Breccia di Commenda (thirteenth century), the eruption continued with a substantial, long- lasting emission of fine ash until activity ceased. Magmatic explosive activity resumed at La Fossa cone at the beginning of the fifteenth century marking the onset of the Gran Cratere cycle. This phase lasted until the mid-sixteenth century and produced at least seven explosive eruptions of intermediate magma composition and a couple of lateral explosions (Forgia Vecchia I and II). During this time interval, a third cinder cone was emplaced at Vulcanello, and the activity produced the lava flows of Punta del Roveto and Valle dei Mostri. From the seventeenth to twentieth centuries, volcanic activity was concentrated at La Fossa cone, where it ended in 1890. This work confirms that Vulcanello island formed in Medieval times between the tenth and eleventh centuries. Moreover, between the tenth and mid-sixteenth centuries, La Fossa caldera was the site of at least 19 eruptions with an average eruption rate of one event every 34 years. This rate makes volcanic hazard at Vulcano higher than that suggested to date.
    Description: Published
    Description: 12
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 24
    Publication Date: 2022-03-16
    Description: In this work, we assess ground shaking in the wider Zagreb area by computing simulated seismograms at regional distances. For the purposes of the simulations, we assemble the 3D velocity and density model and test its performance. First, we compare the low-frequency simulations obtained using deterministic method for both new 3D model and a simple 1D model. We then continue the performance test by computing the full broadband seismo- grams. To do that, we apply the hybrid technique in which the low frequency (f〈1 Hz) and high frequency (f=1–10 Hz) seismograms are obtained separately using deterministic and stochastic method, respectively, and then reconciled into a single time series. We apply this method to the MW=5.3 event and four smaller (3.0〈MW〈5.0) events that occurred in the studied region. We compare simulated data with the recorded seismograms and vali- date our results by calculating the goodness of fit score for peak ground velocity and shak- ing duration. Next, to improve the understanding of the strong ground motion in this area, we simulate seismic shaking scenarios for the 1880, MW = 6.2 earthquake. From computed low-frequency waveforms, we generate shakemaps and compare the ground-motion fea- tures of the two possible sources of this event, Kašina fault and North Medvednica fault. We conduct a preliminary study to determine which fault is a more probable source of the 1880 historic event by comparing the peak ground velocities and Arias intensity with the observed intensities.
    Description: Croatian Science Foundation under the Project No. IP-2020-02-3960 European Commission, H2020 Excel- lence Science [ChEESE (Grant No. 823844)]
    Description: Published
    Description: 167–192
    Description: 1T. Struttura della Terra
    Description: 6T. Studi di pericolosità sismica e da maremoto
    Description: JCR Journal
    Keywords: Numerical simulation ; 3D ground motion ; Earthquake ; Central Croatia ; Zagreb ; Seismic wave propagation ; 3D crustal model ; 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 25
    Publication Date: 2022-03-16
    Description: Geomorphological investigations in Rome’s river valley are revealing the dynamism of the prehistoric landscape. It is becoming increasingly apparent that paleogeographic conditions that defined Rome in the historical era are the product of changes since the Bronze Age, which may be the result of local fault activity in addition to fluvial dynamism. Through a dedicated borehole chronostratigraphic study, integrated by 14C and archaeological dates, and paleomagnetic investigations, we offer here new evidence for fault displacement since ca. 4500 years/BP. We present the failure of the sedimentary fabric of a clay horizon caused by liquefaction processes commonly linked with seismic shaking, interpreting an (ca. 4 m) offset to signify the existence of a fault line located at the foot of the Capitoline Hill. In addition, we show evidence for another (ca. 1 m) offset affecting a stratigraphic horizon in the river channel, occurring along another hypothesized fault line crossing through the Tiber Valley. Movement along this fault may have contributed to a documented phase of fast overflooding dated to the sixth century BCE which eventually led to the birth of the Tiber Island. The most plausible scenario implies progressive deformation, with an average tectonic rate of 2 mm/year, along these inferred fault lines. This process was likely punctuated with moderate earthquakes, but no large event necessarily occurred. Together, the available evidence suggests that during the early centuries of sedentary habitation at the site of Rome, active fault lines contributed to significant changes to the Tiber River valley, capable of challenging lowland activities.
    Description: Published
    Description: 359–378
    Description: 2T. Deformazione crostale attiva
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 26
    Publication Date: 2022-03-16
    Description: In November 2019, the fourth meeting on Volcano Observatory Best Practices workshop was held in Mexico City as a series of talks, discussions, and panels. Volcanologists from around the world offered suggestions for ways to optimize volcano-observatory crisis operations. By crisis, we mean unrest that may or may not lead to eruption, the eruption itself, or its aftermath, all of which require analysis and communications by the observatory. During a crisis, the priority of the observatory should be to acquire, process, analyze, and interpret data in a timely manner. A primary goal is to communicate effectively with the authorities in charge of civil protection. Crisis operations should rely upon exhaustive planning in the years prior to any actual unrest or eruptions. Ideally, nearly everything that observatories do during a crisis should be envisioned, prepared, and practiced prior to the actual event. Pre-existing agreements and exercises with academic and government collaborators will minimize confusion about roles and responsibilities. In the situation where planning is unfinished, observatories should prioritize close ties and communications with the land and civil-defense authorities near the most threatening volcanoes.
    Description: Published
    Description: 3
    Description: 6SR VULCANI – Servizi e ricerca per la società
    Description: N/A or not JCR
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 27
    Publication Date: 2022-01-04
    Description: We present a novel method to estimate dynamic ice loss of Greenland's three largest outlet glaciers: Jakobshavn Isbræ, Kangerlussuaq Glacier, and Helheim Glacier. We use Global Navigation Satellite System (GNSS) stations attached to bedrock to measure elastic displacements of the solid Earth caused by dynamic thinning near the glacier terminus. When we compare our results with discharge, we find a time lag between glacier speedup/slowdown and onset of dynamic thinning/thickening. Our results show that dynamic thinning/thickening on Jakobshavn Isbræ occurs 0.87 ± 0.07 years before speedup/slowdown. This implies that using GNSS time series we are able to predict speedup/slowdown of Jakobshavn Isbræ by up to 10.4 months. For Kangerlussuaq Glacier the lag between thinning/thickening and speedup/slowdown is 0.37 ± 0.17 years (4.4 months). Our methodology and results could be important for studies that attempt to model and understand mechanisms controlling short-term dynamic fluctuations of outlet glaciers in Greenland.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 28
    Publication Date: 2021-11-29
    Description: This work presents a novel empirical Ground Motion prediction Model (GMM) for vertical-to-horizontal (VH) response spectral amplitudes up to 10 s, peak ground acceleration and velocity for shallow crustal earthquakes in Italy. Being calibrated on the most up-to-date strong motion dataset for Italian crustal earthquakes (ITA18), the model is consistent with the ITA18 GMM for the horizontal ground motion. This property makes the model useful in probabilistic seismic hazard assessment for Italy to derive compatible vertical and horizontal response spectra. To account for the increase of VH ratios in the proximity of the seismic source, an adjustment term is introduced to improve the prediction capability of the model in near-source conditions, relying on the worldwide NEar-Source Strong motion dataset (NESS). The proposed model uses a simple functional form restricted to a limited number of predictor variables, namely, magnitude, source-to-site distance, focal mechanism, and site effects, and the variability associated with both VH and V models is provided.
    Description: Published
    Description: 4121-4141
    Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 29
    Publication Date: 2021-12-09
    Description: Risk assessments in volcanic contexts are complicated by the multi-hazard nature of both unrest and eruption phases, which frequently occur over a wide range of spatial and temporal scales. As an attempt to capture the multi-dimensional and dynamic nature of volcanic risk, we developed an integrAteD VolcanIc risk asSEssment (ADVISE) model that focuses on two temporal dimensions that authorities have to address in a volcanic context: short-term emergency management and long-term risk management. The output of risk assessment in the ADVISE model is expressed in terms of potential physical, functional, and systemic damage, determined by combining the available information on hazard, exposed systems and vulnerability. The ADVISE model permits qualitative, semi-quantitative and quantitative risk assessment depending on the final objective and on the available information. The proposed approach has evolved over a decade of study on the volcanic island of Vulcano (Italy), where recent signs of unrest combined with uncontrolled urban development and significant seasonal variations of exposed population result in highly dynamic volcanic risk. For the sake of illustration of all the steps of the ADVISE model, we focus here on the risk assessment of the transport system in relation to the tephra fallout associated with a long-lasting Vulcanian cycle.
    Description: Published
    Description: 7
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: N/A or not JCR
    Keywords: Emergency management; Functional vulnerability; Hazard; Physical vulnerability; Risk assessment; Risk management; Systemic vulnerability; Vulcano island
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 30
    Publication Date: 2021-12-15
    Description: The Campi Flegrei volcano (or Phlegraean Fields), Campania, Italy, generated the largest eruption in Europe in at least 200 ka. Here we summarise the volcanic and human history of Campi Flegrei and discuss the interactions between humans and the environment within the “burning felds” from around 10,000 years until the 1538 CE Monte Nuovo eruption and more recent times. The region’s incredibly rich written history documents how the landscape changed both naturally and anthropogenically, with the volcanic system fuelling these considerable natural changes. Humans have exploited the beautiful landscape, accessible resources (e.g. volcanic ash for pulvis puteolana mortar) and natural thermal springs associated with the volcano for millennia, but they have also endured the downsides of living in a volcanically active region—earthquakes, signifcant ground deformation and landscape altering eruptions. The pre-historic record is detailed, and various archaeological sites indicate that the region was certainly occupied in the last 10,000 years. This history has been reconstructed by identifying archaeological fnds in sequences that often contain ash (tephra) layers from some of the numerous volcanic eruptions from Campi Flegrei and the other volcanoes in the region that were active at the time (Vesuvius and Ischia). These tephra layers provide both a relative and absolute chronology and allow the archaeology to be placed on a relatively precise timescale. The records testify that people have inhabited the area even when Campi Flegrei was particularly active.The archaeological sequences and outcrops of pyroclastic material preserve details about the eruption dynamics, buildings from Roman times, impressive craters that now host volcanic lakes and nature reserves, all of which make this region particularly mystic and fascinating, especially when we observe how society continues to live within the active caldera system. The volcanic activity and long record of occupation and use of volcanic resources in the region make it unique and here we outline key aspects of its geoheritage.
    Description: Published
    Description: 5
    Description: 1V. Storia eruttiva
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: 6SR VULCANI – Servizi e ricerca per la società
    Description: JCR Journal
    Keywords: Archaeology ; Campania ; Campi Flegrei volcano ; History ; Human
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 31
    Publication Date: 2021-12-15
    Description: Here, we report on the Quaternary Volsci Volcanic Field (VVF, central Italy). In light of new 40Ar/39Ar geochronological data and compositional characterization of juvenile eruptive products, we refine the history of VVF activity, and outline the implications on the pre-eruptive magma system and the continental subduction processes involved. Different from the nearby volcanic districts of the Roman and Campanian Provinces, the VVF was characterized by small-volume (0.01–0.1 km3) eruptions from a network of monogenetic centers (mostly tuff rings and scoria cones, with subordinate lava occurrences), clustered along high-angle faults of lithospheric depth. Leucite-bearing, high-K (HKS) magmas (for which we report for the first time the phlogopite phenocryst compositions) mostly fed the early phase of activity (∼761–539 ka), then primitive, plagioclase-bearing (KS) magmas appeared during the climactic phase (∼424–349 ka), partially overlapping with HKS ones, and then prevailed during the late phase of activity (∼300–231 ka). The fast ascent of primitive magma batches is typical of a tectonically controlled volcanic field, where the very low magma flux is a passive byproduct of regional tectonic strain. We suggest that the dominant compressive stress field acting at depth was accompanied by an extensional regime in the upper crust, associated with the gravity spreading of the Apennine chain, allowing the fast ascent of magma from the mantle source with limited stationing in shallow reservoirs.
    Description: Published
    Description: 689–718
    Description: 1V. Storia eruttiva
    Description: JCR Journal
    Keywords: Quaternary volcanism ; 40Ar/39Ar geochronology ; Tyrrhenian Sea margin ; Central Italy
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 32
    Publication Date: 2021-12-15
    Description: Numerical results of a two-layer depth-averaged model of pyroclastic density currents (PDCs) were compared with an experimental PDC generated at the international eruption simulator facility (the Pyroclastic flow Eruption Large-scale Experiment (PELE)) to establish a minimal dynamical model of PDCs with stratification of particle concentrations. In the present two-layer model, the stratification in PDCs is modeled as a voluminous suspended-load layer with low particle volume fractions ( ≲ 10−3) and a thin basal bed-load layer with higher particle volume fractions ( ∼ 10−2 ) on the basis of the source condition in the experiment. Numerical results for the suspended load quantitatively reproduce the time evolutions of the front position and flow thickness in the experimental PDC. The numerical results of the bed-load and deposit thicknesses depend on an assumed value of settling speed at the bottom of the bed load ( WsH ). We show that the thicknesses of bed load and deposit in the simulations agree well with the experimental data, when WsH is set to about 1.25 × 10−2 m/s. This value of the settling speed is two orders of magnitude smaller than that predicted by a hindered-settling model. The small value of WsH is considered to result from decreasing in the effective deposition speed due to the erosion process accompanied by saltating/rolling of particles at the bottom of the bed load.
    Description: Published
    Description: 73
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: JCR Journal
    Keywords: Pyroclastic density current ; Two-layer model ; Experimental validation ; Pyroclastic surge ; Bed load ; Sedimentation process Introduction ; 04.08. Volcanology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 33
    Publication Date: 2021-12-16
    Description: A new analysis of high-resolution multibeam and seismic reflection data, collected during several oceanographic expeditions starting from 1999, allowed us to compile an updated morphotectonic map of the North Anatolian Fault below the Sea of Marmara. We reconstructed kinematics and geometries of individual fault segments, active at the time scale of 10 ka, an interval which includes several earthquake cycles, taking as stratigraphic marker the base of the latest marine transgression. Given the high deformation rates relative to sediment supply, most active tectonic structures have a morphological expression at the seafloor, even in presence of composite fault geometries and/or overprinting due to mass-wasting or turbidite deposits. In the frame of the right-lateral strike-slip domain characterizing the North Anatolian fault system, three types of deformation are observed: almost pure strike-slip faults, oriented mainly E–W; NE/SW-aligned axes of transpressive structures; NW/SE-oriented trans-tensional depressions. Fault segmentation occurs at different scales, but main segments develop alongthree major right-lateral oversteps, which delimit main fault branches, from east to west: (i) the transtensive Cinarcik segment; (ii) the Central (East and West) segments; and (iii) the westernmost Tekirdag segment. A quantitative morphometric analysis of the shallow deformation patterns observed by seafloor morphology maps and high-resolution seismic reflection profiles along the entire basin allowed to determine nature and cumulative lengths of individual fault segments. These data were used as inputs for empirical relationships, to estimate maximum expected Moment Magnitudes, obtaining values in the range of 6.8–7.4 for the Central, and 6.9–7.1 for the Cinarcik and Tekirdag segments, respectively. We discuss these findings considering analyses of historical catalogues and available paleoseismological studies for the Sea of Marmara regionto formulate reliable seismic hazard scenarios.
    Description: Published
    Description: 29–44
    Description: 6T. Studi di pericolosità sismica e da maremoto
    Description: N/A or not JCR
    Keywords: North Anatolian fault · ; Sea of Marmara ; Earthquakes ; Active fault segments ; Marine geophysics ; Seismic hazard ; 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 34
    Publication Date: 2021-12-16
    Description: Diffusive gradients in thin fi lms (DGT) have been tested in CO2-rich, metal-bearing fl uids from springs in the Campo de Calatrava region in Central Spain, to assess their applicability as a monitoring tool in onshore CO2 storage projects. These fi lms are capable of adsorbing metals and recording changes in their concentration in water, sediments, and soils. Considering that CO2 dissolution promotes metal solubilization and transport, the use of these fi lms could be valuable as a monitoring tool of early leakage. A number of DGT have been deployed in selected springs with constant metal concentration. The studied waters show high concentrations of Fe, as high as 1 × 104 μg·L–1, Ni, Co, Zn, Cu, and Mn. Comparing re-calculated metal concentration in DGT with metal water concentration, two different metal behaviors are observed: (i) metals with sorption consistent with the metal concentration (i.e. plotting close to the 1:1 line in a [Me]DGT: [Me]water plot), and (ii) metals with non–linear sorption, with some data showing metal enrichment in DGT compared with the concentration in water. Metals in the fi rst group include Fe, Mn, Co, Ni, and U, and metals in the second group are Zn, Pb, Cr, Cu, and Al. From this research, it is concluded that the metals in the fi rst group can be used to monitor potential leakage by using DGT, providing effective leakage detection even considering low variations of concentrations, episodic metal release, and reducing costs compared with conventional, periodic water sampling.
    Description: Published
    Description: 163-175
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Campo de Calatrava ; CO2 storage and leakage ; DGT ; metal leakage ; metal transport ; trace metals ; 03.04. Chemical and biological ; 05.04. Instrumentation and techniques of general interest
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 35
    Publication Date: 2021-12-22
    Description: Future occurrence of explosive eruptive activity at Cotopaxi and Guagua Pichincha volcanoes, Ecuador, is assessed probabilistically, utilizing expert elicitation. Eight eruption types were considered for each volcano. Type event probabilities were evaluated for the next eruption at each volcano and for at least one of each type within the next 100 years. For each type, we elicited relevant eruption source parameters (duration, average plume height, and total tephra mass). We investigated the robustness of these elicited evaluations by deriving probability uncertainties using three expert scoring methods. For Cotopaxi, we considered both rhyolitic and andesitic magmas. Elicitation findings indicate that the most probable next eruption type is an andesitic hydrovolcanic/ash-emission (~ 26–44% median probability), which has also the highest median probability of recurring over the next 100 years. However, for the next eruption at Cotopaxi, the average joint probabilities for sub-Plinian or Plinian type eruption is of order 30–40%—a significant chance of a violent explosive event. It is inferred that any Cotopaxi rhyolitic eruption could involve a longer duration and greater erupted mass than an andesitic event, likely producing a prolonged emergency. For Guagua Pichincha, future eruption types are expected to be andesitic/dacitic, and a vulcanian event is judged most probable for the next eruption (median probability ~40–55%); this type is expected to be most frequent over the next 100 years, too. However, there is a substantial probability (possibly 〉40% in average) that the next eruption could be sub-Plinian or Plinian, with all that implies for hazard levels.
    Description: Published
    Description: 35
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 36
    Publication Date: 2021-12-22
    Description: We present a new geometrical method capable of quantifying and illustrating the outcomes of a three-component mixing dynamics. In a three-component mixing sce nario, classical algebraic equations and endmember mixing analysis (EMMA) can be used to quantify the contributions from each fraction. Three-component mixing of natural waters, either in an element–element plot or by using the EMMA mixing sub space is described by a triangular shaped distribution of sample points where each endmember is placed on an apex, while each side corresponds to the mixing function of the two endmembers placed at the apex, considering the third endmembers' con tribution equal to zero. Along each side, the theoretical mixing fractions can be com puted using mass balance equations. Samples with contributions from three endmembers will plot inside the triangle, while the homogeneous barycentric coordi nate projections can be projected onto the three sides. The geochemistry observed in the mineralized Ferrarelle aquifer system (southern Italy) results from three component mixing of groundwater, each with diagnostic geochemical compositions. The defined boundary conditions allow us to parameterize and validate the proce dures for modelling mixing, including selection of suitable geochemical tracer
    Description: Published
    Description: e14409
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 37
    Publication Date: 2021-12-22
    Description: Exposure to volcanic ash is a long-standing health concern for people living near active volcanoes and in distal urban areas. During transport and deposition, ash is subjected to various physicochemical processes that may change its surface composition and, consequently, bioreactivity. One such process is the interaction with anthropogenic pollutants; however, the potential for adsorbed, deleterious organic compounds to directly impact human health is unknown. We use an in vitro bioanalytical approach to screen for the presence of organic compounds of toxicological concern on ash surfaces and assess their biological potency. These compounds include polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzop- dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dlPCBs). Analysis of ash collected in or near urbanised areas at five active volcanoes across the world (Etna, Italy; Fuego, Guatemala; Kelud, Indonesia; Sakurajima, Japan; Tungurahua, Ecuador) using the bioassay inferred the presence of such compounds on all samples. A relatively low response to PCDD/Fs and the absence of a dlPCBs response in the bioassay suggest that the measured activity is dominated by PAHs and PAH-like compounds. This study is the first to demonstrate a biological potency of organic pollutants associated with volcanic ash particles. According to our estimations, they are present in quantities below recommended exposure limits and likely pose a low direct concern for human health.
    Description: Published
    Description: 30
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 38
    Publication Date: 2021-11-26
    Description: Integrating palaeoclimatological proxies and historical records, which is necessary to achieve a more complete understanding of climate impacts on past societies, is a challenging task, often leading to unsatisfactory and even contradictory conclusions. This has until recently been the case for Italy, the heart of the Roman Empire, during the transition between Antiquity and the Middle Ages. In this paper, we present new high-resolution speleothem data from the Apuan Alps (Central Italy). The data document a period of very wet conditions in the sixth c. AD, probably related to synoptic atmospheric conditions similar to a negative phase of the North Atlantic Oscillation. For this century, there also exist a significant number of historical records of extreme hydroclimatic events, previously discarded as anecdotal. We show that this varied evidence reflects the increased frequency of floods and extreme rainfall events in Central and Northern Italy at the time. Moreover, we also show that these unusual hydroclimatic conditions overlapped with the increased presence of "water miracles" in Italian hagiographical accounts and social imagination. The miracles, performed by local Church leaders, strengthened the already growing authority of holy bishops and monks in Italian society during the crucial centuries that followed the "Fall of the Roman Empire". Thus, the combination of natural and historical data allows us to show the degree to which the impact of climate variability on historical societies is determined not by the nature of the climatic phenomena per se, but by the culture and the structure of the society that experienced it.
    Description: Published
    Description: 25
    Description: 5A. Ricerche polari e paleoclima
    Description: JCR Journal
    Keywords: Precipitation ; Roman Empire ; miracles ; Social feedbacks ; Cultural change ; climate change
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 39
    Publication Date: 2021-12-09
    Description: Volcano-hydrothermal systems are governed by complex interactions between fluid transport, and geochemical and mechanical processes. Evidence of this close interplay has been testified by distinct spatial and temporal correlations in geochemical and geophysical observations at Vulcano Island (Italy). To understand the interaction between fluid circulation and the geochemical and geophysical manifestations, we perform a parametric study to explore different scenarios by implementing a hydro-geophysical model based on the equations for heat and mass transfer in a porous medium and thermo-poroelastic theory. Numerical simulations allow us to define the controlling role of permeability distribution on the different modeled parameters as well as on the geophysical observables. Changes in the permeability within the highly fractured crater area could be responsible for the fluctuations in gas emission and temperature recorded during the crisis periods, which are accompanied by shallow volcano-seismicity in the absence of significant deformation and gravity variations. Despite the general medium permeability of the volcanic edifice, the presence of more highly permeable pathways, which allow the gas to rapidly escape, as testified by the presence of a well-developed fumarolic field, prevents the pressure buildup at shallow depths.
    Description: Published
    Description: 179
    Description: 4V. Processi pre-eruttivi
    Description: JCR Journal
    Keywords: Hydrothermal system ; Parametric simulation ; Vulcano Island ; Hydro-geophysical model
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 40
    Publication Date: 2021-12-09
    Description: Lahars are rapid flows composed of water and volcaniclastic sediments, which have the potential to impact residential buildings and critical infrastructure as well as to disrupt critical services, especially in the absence of hazard-based land-use planning. Their destructive power is mostly associated with their velocity (related to internal flow properties and topographic interactions) and to their ability to bury buildings and structures (due to deposit thickness). The distance reached by lahars depends on their volume, on sediments/water ratio, as well as on the geometrical properties of the topography where they propagate. Here we present the assessment of risk associated with lahar using Vulcano island (Italy) as a case study. First, we estimated an initial lahar source volume considering the remobilisation by intense rain events of the tephra fallout on the slopes of the La Fossa cone (the active system on the island), where the tephra fallout is associated with the most likely scenario (e.g. long-lasting Vulcanian cycle). Second, we modelled and identified the potential syn-eruptive lahar impact areas on the northern sector of Vulcano, where residential and touristic facilities are located. We tested a range of parameters (e.g., entrainment capability, consolidation of tephra fallout deposit, friction angle) that can influence lahar propagation output both in terms of intensity of the event and extent of the inundation area. Finally, exposure and vulnerability surveys were carried out in order to compile exposure and risk maps for lahar-flow front velocity (semi-quantitative indicator-based risk assessment) and final lahar-deposit thickness (qualitative exposure-based risk assessment). Main outcomes show that the syn-eruptive lahar scenario with medium entrainment capability produces the highest impact associated with building burial by the final lahar deposit. Nonetheless, the syn-eruptive lahar scenario with low entrainment capacity is associated with higher runout and results in the highest impact associated with lahar-flow velocities. Based on our simulations, two critical infrastructures (telecommunication and power plant), as well as the main road crossing the island are exposed to potential lahar impacts (either due to lahar-flow velocity or lahar-deposit thickness or both). These results show that a risk-based spatial planning of the island could represent a valuable strategy to reduce the volcanic risk in the long term.
    Description: Published
    Description: 9
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: N/A or not JCR
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  • 41
    Publication Date: 2021-12-23
    Description: Gender equality is a fundamental human right, embedded into the United Nations Charter (1945). Women still face multiple forms of discrimination, harassment and abuse. Gender equality is foundational to ensuring inclusive sustainable socio-economic development, peace and justice.
    Description: Published
    Description: 105-126
    Description: 1TM. Formazione
    Description: 3TM. Comunicazione
    Keywords: gender equality ; sustainable development goals ; geosciences ; geoethics ; women ; girls ; 05.03. Educational, History of Science, Public Issues ; 05.09. Miscellaneous
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
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  • 42
    Publication Date: 2021-12-13
    Description: Hydrogeoethics is an emergent transdisciplinary field in geosciences focused on ethical research and best practices related to responsible groundwater science and engineering, creating conditions for sustainable water resources management while respecting human needs and environmental dynamics.
    Description: Published
    Description: 289–292
    Description: 1TR. Georisorse
    Description: N/A or not JCR
    Keywords: Hydrogeoethics ; Geoethics ; Water resources ; Water management ; Water scarcity ; Sustainability ; Mediterranea region ; 03.02. Hydrology ; 05.03. Educational, History of Science, Public Issues ; 05.09. Miscellaneous
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 43
    Publication Date: 2021-12-10
    Description: Groundwater close to three municipal solid waste landfll sites in Sicily (southern Italy) was sampled to determine the presence of contaminants and the risk associated with its possible use as drinking and sanitary water. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and metals were investigated. These target compounds are the most common pollutants present in leachates. Risk Assessment Guidance for Superfund (RAGS, US EPA) was used to assess human health risk. Ingestion, dermal, and total exposure to these xenobiotic contaminants in groundwater were evaluated, and the cancer and non-cancer risk indexes were calculated. The results revealed that, while the groundwater complied with Italian Drinking Water Directive 30/2001, it did not comply with the "good environmental state" criteria of Directive 30/2009 at two of the three sites investigated. Worrying results were revealed by the risk assessment at the investigated sites. Cancer and non-cancer risk indexes indicated a probable risk, mainly due to dermal exposure to groundwater. These results underline the importance of assessing the risk for all possible routes, evaluating not only ingestion but also dermal exposure, especially when organic pollutants are present. The results of this study show that human health risk has probably been underestimated in the past, as dermal exposure to organic pollutants has only rarely been evaluated in the literature.
    Description: Published
    Description: 535–550
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Human health risk ; Polycyclic aromatic hydrocarbons ; Polychlorinated biphenyls ; Dioxin PCDD/Fs ; Toxic elements ; Environmental quality standard
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 44
    Publication Date: 2021-11-25
    Description: The island of Ischia, located in the Gulf of Naples, represents an unusual case of resur- gent caldera where small-to-moderate magnitude volcano-tectonic earthquakes generate large damage and catastrophic e ects, as in the case of 4 March 1881 (Imax-VIII-IXMCS) and 28 July 1883 (Imax X-XI MCS) historical earthquakes, and of the recent 21 August 2017 MW=3.9, event. All these earthquakes struck the northern area of the island. With about 65,000 inhabitants, Ischia is a popular touristic destination for thermals baths, host- ing more than 3,000,000 visitors per year, thus representing a high seismic risk area. Assessing its seismic potential appears a fundamental goal and, to this end, the estimate of the magnitude of signi cant historical events and the characterization of their source are crucial. We report here a reassessment of historical data of damage of 1881 and 1883 earth- quakes to evaluate the main source parameters of these events (obtained with the BOXER and EXISM software) and quantitatively compare, for the rst time, the results with the source characteristics, obtained from instrumental data, of the recent 2017 earthquake. The results allowed us to assess the location, as well as the possible dimension and the related maximum magnitude, of the seismogenic structure responsible for such damaging earth- quakes. Our results also provide an additional framework to de ne the mechanisms leading to earthquakes associated with the dynamics of calderas.
    Description: Published
    Description: 177–201
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 45
    Publication Date: 2021-11-26
    Description: The AD 1761 eruption on Terceira was the onlyhistorical subaerial event on the island and one of the lastrecorded in the Azores. The eruption occurred along the fis-sure zone that crosses the island and produced a trachybasaltlava flow and scoria cones. Small comenditic trachyte lava domes (known as Mistérios Negros) were also thought by some to have formed simultaneously on the eastern flank of Santa Bárbara Volcano. Following a multidisciplinary approach, we combined geological mapping, paleomagnetic, petrographic, mineral and whole-rock geochemical and structural analyses to study this eruption. The paleomagnetic dating method compared geomagnetic vectors (directions and intensities) recorded by both the AD 1761 lava flow and Mistérios Negros domes and revealed that the two events were indeed coeval. Based on new data and interpretation of historical records, we have accordingly reconstructed the AD 1761eruptive dynamics and distinguished three phases: (1) a pre-cursory phase characterized by decreased degassing in the fumarolic field of Pico Alto Volcano and a gradual increase of seismic activity, which marked the intrusion of trachybasalt magma; (2) a first eruptive phase that started with phreatic explosions on the eastern flank of Santa Bárbara Volcano, followed by the inconspicuous effusion of comenditic trachyte (66 wt% SiO2), forming a WNW-ESE-oriented chain of lava domes; and (3) a second eruptive phase on the central part ofthe fissure zone, where a Hawaiian to Strombolian-style erup-tion formed small scoria cones (E-W to ENE-WSW-oriented)and a trachybasalt lava flow (50 wt% SiO2) which buried 27houses in Biscoitos village. Petrological analyses show thatthe two batches of magma were emitted independently without evidence of interaction. We envisage that the dome-forming event was triggered by local stress changes induced by intrusion of the trachybasalt dyke along the fissure zone, which created tensile stress conditions that promoted ascent of comenditic trachyte magma stored beneath Santa Bárbara Volcano.
    Description: Published
    Description: 22
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 46
    Publication Date: 2022-05-24
    Description: We have reinterpreted the causative fault parameters of the 2005 Zarand earthquake in the light of a new imagery study using Interferometric Synthetic Aperture Radar (InSAR). By conducting a joint inversion of two InSAR datasets, we can characterize the rupture as it relates to complex local structures. At first, the mainshock ruptured a nearly pure reverse fault, dipping ~65° NNW in the basement below the southeastern area of Zarand. Two more fault segments were subsequently activated: an oblique‐normal fault segment parallel to the first segment, dipping 61° to the south, and a normal‐oblique fault segment at the eastern termination of the rupture zone. The first fault segment ruptured the surface, while slip along the other two segments was confined to the lower sedimentary strata.
    Description: Published
    Description: 274-283
    Description: 2T. Deformazione crostale attiva
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 47
    Publication Date: 2022-06-22
    Description: The Riardo basin hosts groundwater exploited for the production of high quality, naturally sparkling, bottled water (e.g., Ferrarelle water), and circulating in a system constituted by highly fractured Mesozoic carbonates, overlain by more impervious volcanic rocks of the Roccamonfina complex. The two formations are locally in hydraulic connection and dislocated by deep-rooted faults. The study aimed at elucidating groundwater origin and circulation, using isotopic tracers (δ18O, δ2H, δ11B and 87Sr/86Sr) coupled to groundwater dating (Tritium, CFCs and SF6). Besides recharge by local precipitation over the Riardo hydrogeological basin, stable isotope ratios in water indicated an extra-basin recharge, likely from the elevated surrounding carbonate reliefs (e.g., Maggiore and Matese Mts.). The mineralization process, promoted by the deep CO2 flux, controls the B and Sr contents. However, their isotopic ratios did not allow discriminating between circulation in the volcanic and in the carbonate aquifers, as in the latter the isotopic composition differed from the original marine signature. Groundwater model ages ranged from ~ 30 years for the volcanic endmember to 〉 70 years for the deep, mineralized end-member, with longer circuits recharged at higher elevations. Overall, the results of this study were particularly relevant for mineral water exploitation. A recharge from outside the hydrogeological basin could be evidenced, especially for the more mineralized and valuable groundwater, and an active recent recharge was detected for the whole Riardo system. Both findings will contribute to the refinement of the hydrogeological model and water budget, and to a sustainable development of the resource.
    Description: Published
    Description: 1–28
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Aquifer recharge; Fractured aquifers; Groundwater dating; Hydrogeological circuits; Stable isotopes
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 48
    Publication Date: 2022-06-22
    Description: El Niño-Southern Oscillation (ENSO) is known to affect the Northern Hemisphere tropospheric circulation in late-winter (January–March), but whether El Niño and La Niña lead to symmetric impacts and with the same underlying dynamics remains unclear, particularly in the North Atlantic. Three state-of-the-art atmospheric models forced by symmetric anomalous sea surface temperature (SST) patterns, mimicking strong ENSO events, are used to robustly diagnose symmetries and asymmetries in the extra-tropical ENSO response. Asymmetries arise in the sea-level pressure (SLP) response over the North Pacific and North Atlantic, as the response to La Niña tends to be weaker and shifted westward with respect to that of El Niño. The difference in amplitude can be traced back to the distinct energy available for the two ENSO phases associated with the non-linear diabatic heating response to the total SST field. The longitudinal shift is embedded into the large-scale Rossby wave train triggered from the tropical Pacific, as its anomalies in the upper troposphere show a similar westward displacement in La Niña compared to El Niño. To fully explain this shift, the response in tropical convection and the related anomalous upper-level divergence have to be considered together with the climatological vorticity gradient of the subtropical jet, i.e. diagnosing the tropical Rossby wave source. In the North Atlantic, the ENSO-forced SLP signal is a well-known dipole between middle and high latitudes, different from the North Atlantic Oscillation, whose asymmetry is not indicative of distinct mechanisms driving the teleconnection for El Niño and La Niña.
    Description: Published
    Description: 1965–1986
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
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  • 49
    Publication Date: 2022-06-22
    Description: A theoretical pattern for Fe and As co-precipitation was tested directly in a groundwater natural system. Several monitoring wells were sampled to identify the different endmembers that govern the hydrodynamics of the Ferrarelle Groundwater System in the Riardo Plain (Southern Italy). In agreement with recent investigations, we found a mix of a deep and a shallow component in different proportions, resulting in a specific chemical composition of groundwater in each well depending on the percentages of each component. The shallow component was characterized by EC ~ 430 µS/cm, Eh ~ 300 mV, Fe ~ 0.06 µmol/L and As ~ 0.01-0.12 µmol/L, while the deep component was characterized by EC ~ 3400 µS/cm, Eh ~ 170 mV, Fe ~ 140 µmol/L and As ~ 0.59 µmol/L. A general attenuation of As and Fe concentration that was not due to a simple dilution effect was observed in the mixing process. The oxidation of Fe(II) to Fe(III) produces solid precipitates which adsorb As from solution and then co-precipitate. The reactions pattern of Fe(II) oxidation and As adsorption gave a linear function between [As] and [Fe], where the angular coefficient depends on the [O2]/[H+] ratio. Chemical data obtained from our samples showed a very good agreement with this theoretical relationship. The investigated geochemical dynamics represented a natural process of attenuation of Fe and As, two undesirable elements that usually affect groundwater quality in volcanic aquifers in central-southern Italy, which are exploited to supply drinking water.
    Description: Published
    Description: pages 2065–2082
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Fe and As hydrogeochemistry; Natural mineral water; Natural self-removal dynamics; Oxohydroxides adsorption; Water treatment
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 50
    Publication Date: 2022-06-22
    Description: Geothermal areas of Greece are located in regions affected by recent volcanism and in continental basins characterised by elevated heat flow. Many of them are found along the coast and thus, water is often saline due to marine intrusion. In the current study, we present about 300 unpublished and literature data from thermal and cold mineral waters collected along Greece. Samples were analysed for major ions, Li, SiO2 and isotopes in water. Measured temperatures range from 6.5 to 98°C, pH from 1.96 to 11.98, whilst Total Dissolved Solutes (TDS) from 0.22 to 51 g/L. Waters were subdivided into four main groups: i) thermal; ii) cold; iii) acidic (pH 〈5) and iv) hyperalkaline (pH 〉11). On statistical basis, the thermal waters were subdivided into subgroups according to both their temperature [warm (〈29 °C), hypothermal (29-48 °C), thermal (48-75 °C) and hyperthermal (〉75 °C)] and TDS [low salinity (〈4 g/L), brackish (4-30 g/L) and saline (〉30 g/L)]. Cold waters were subdivided basing on their pCO2 [low (〈0.05 atm), medium (0.05-0.85 atm) and high (〉0.85 atm)]. δ18O-H2O ranges from -12.7 to +2.7 ‰ vs. SMOW, while δ2H-H2O from -91 to +12 ‰ vs. SMOW being generally comprised between the Global Meteoric Water Line and the East Mediterranean Meteoric Water Line. Positive δ18O shifts with respect to the former are mostly related to mixing with seawater, while only for a few samples they point to high-temperature water-rock interaction processes. Only a few thermal waters gave reliable geothermometric estimates, suggesting reservoir temperatures between 80 and 260 °C.
    Description: Published
    Description: 2111–2133
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Hydrogeochemistry ; Stable isotopes ; Carbon dioxide ; Geothermometry ; 03. Hydrosphere ; 03.04. Chemical and biological
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  • 51
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-26
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2021.
    Description: This thesis explores the volatile content of the mantle, subducted oceanic crust, and arc magmas as well as the structure of slow spreading ocean crust and the heterogeneity of Earth’s upper mantle. In Chapter 2, I directly explore the halogen (F and Cl) content of mantle minerals in situ, then use these measurements to assess the halogen content of the upper mantle. In Chapter 3, I investigate the volatile content of Raspas eclogites (SW Ecuador), a proxy for deeply subducted oceanic crust, to evaluate volatile transfer from crustal generation at divergent plate boundaries (e.g., mid-ocean ridges) to recycling of ocean crust at subduction zones. In Chapter 4, I use the H2O content of nominally anhydrous minerals in plutonic arc cumulates to elucidate the H2O content of the melts from which the rocks crystallized. In this way, I assert that primitive arc magmas may contain 4–10 wt.% H2O and through fractional crystallization up to ~20 wt.% H2O, making them far more hydrous than traditional methods (i.e., olivine-hosted melt inclusions) surmise. In Chapter 5, I show that mantle peridotite exposed along the 16ºN region of the Mid-Atlantic Ridge originated in an arc setting and has been remixed into subridge mantle, indicating that the sub-ridge mantle is more heterogeneous and depleted than inferences made from mid-ocean ridge basalts suggest. Chapter 6 surveys the life cycle of oceanic core complexes through zircon geochronology and posits an updated framework for understanding the termination of oceanic core complexes, and more broadly oceanic detachment faults. Together, this contribution highlights the chemical heterogeneity of the mantle, and quantifies the full extent of volatiles hosted by mantle and crustal reservoirs.
    Description: The Stanley Watson Fellowship (WHOI) provided financial support during my first year of graduate school. The Academic Programs Office Ocean Venture Fund (WHOI) provided seed funding which initiated Chapters 3 and 4, and ultimately led to two funded NSF proposals. These resources are vital to JP students, and I am incredibly grateful for them. Primary support was provided by the National Science Foundation grants to Veronique Le Roux (EAR P&G #1524311, #1839128, #1855302) and Henry Dick (MG&G #1637130, #1657983).
    Keywords: Geochemistry of the crust and mantle ; Volatile elements ; Tectonics
    Repository Name: Woods Hole Open Access Server
    Type: Thesis
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  • 52
    Publication Date: 2022-10-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Jin, D., Hoagland, P., & Ashton, A. D. Risk averse choices of managed beach widths under environmental uncertainty. Natural Resource Modeling, (2021): e12324, https://doi.org/10.1111/nrm.12324.
    Description: Applying a theoretical geo-economic approach, we examined key factors affecting decisions about the choice of beach width when eroded coastal beaches are being nourished (i.e., when fill is placed to widen a beach). Within this geo-economic framework, optimal beach width is positively related to its values for hazard protection and recreation and negatively related to nourishment costs and the discount rate. Using a dynamic modeling framework, we investigated the time paths of beach width and nourishment that maximized net present value under an accelerating sea level. We then analyzed how environmental uncertainty about expected future beach width, arising from natural shoreline dynamics, intermittent large storms, or sea-level rise, leads to economic choices favoring narrower beaches. Risk aversion can affect a coastal property owner's choice of beach width in contradictory ways: the expected benefits of hazard protection must be balanced against the expected costs of repeated nourishment actions.
    Description: Support for this study was provided by NSF Grant No. ARG 1518503, WHOI Sea Grant (NOAA Award Number: NA18OAR4170104), and the J. Seward Johnson Fund in Support of the Marine Policy Center.
    Keywords: Beach nourishment ; Beach width ; Coastal protection ; Risk management ; Shoreline change
    Repository Name: Woods Hole Open Access Server
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  • 53
    Publication Date: 2022-10-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Farrell, U. C., Samawi, R., Anjanappa, S., Klykov, R., Adeboye, O. O., Agic, H., Ahm, A.-S. C., Boag, T. H., Bowyer, F., Brocks, J. J., Brunoir, T. N., Canfield, D. E., Chen, X., Cheng, M., Clarkson, M. O., Cole, D. B., Cordie, D. R., Crockford, P. W., Cui, H., Dahl, T. W., Mouro, L. D., Dewing, K., Dornbos, S. Q., Drabon, N., Dumoulin, J. A., Emmings, J. F., Endriga, C. R., Fraser, T. A., Gaines, R. R., Gaschnig, R. M., Gibson, T. M., Gilleaudeau, G. J., Gill, B. C., Goldberg, K., Guilbaud, R., Halverson, G. P., Hammarlund, E. U., Hantsoo, K. G., Henderson, M. A., Hodgskiss, M. S. W., Horner, Tristan J., Husson, J. M., Johnson, B., Kabanov, P., Brenhin K. C., Kimmig, J., Kipp, M. A., Knoll, A. H., Kreitsmann, T., Kunzmann, M., Kurzweil, F., LeRoy, M. A., Li, C., Lipp, A. G., Loydell, D. K., Lu, X., Macdonald, F. A., Magnall, J. M., Mänd, K., Mehra, A., Melchin, M. J., Miller, A. J., Mills, N. T., Mwinde, C. N., O'Connell, B., Och, L. M., Ossa Ossa, F., Pagès, A., Paiste, K., Partin, C. A., Peters, S. E., Petrov, P., Playter, T. L., Plaza-Torres, S., Porter, Susannah M., Poulton, S. W., Pruss, S. B., Richoz, S., Ritzer, S. R., Rooney, A. D., Sahoo, S. K., Schoepfer, S. D., Sclafani, J. A., Shen, Y., Shorttle, O., Slotznick, S. P., Smith, E. F., Spinks, S., Stockey, R. G., Strauss, J. V., Stüeken, E. E., Tecklenburg, S., Thomson, D., Tosca, N. J., Uhlein, G. J., Vizcaíno, M. N., Wang, H., White, T., Wilby, P. R., Woltz, C. R., Wood, R. A., Xiang, L., Yurchenko, I. A., Zhang, T., Planavsky, N. J., Lau, K. V., Johnston, D. T., Sperling, E. A., The Sedimentary Geochemistry and Paleoenvironments Project. Geobiology. 00, (2021): 1– 12,https://doi.org/10.1111/gbi.12462.
    Description: Geobiology explores how Earth's system has changed over the course of geologic history and how living organisms on this planet are impacted by or are indeed causing these changes. For decades, geologists, paleontologists, and geochemists have generated data to investigate these topics. Foundational efforts in sedimentary geochemistry utilized spreadsheets for data storage and analysis, suitable for several thousand samples, but not practical or scalable for larger, more complex datasets. As results have accumulated, researchers have increasingly gravitated toward larger compilations and statistical tools. New data frameworks have become necessary to handle larger sample sets and encourage more sophisticated or even standardized statistical analyses. In this paper, we describe the Sedimentary Geochemistry and Paleoenvironments Project (SGP; Figure 1), which is an open, community-oriented, database-driven research consortium. The goals of SGP are to (1) create a relational database tailored to the needs of the deep-time (millions to billions of years) sedimentary geochemical research community, including assembling and curating published and associated unpublished data; (2) create a website where data can be retrieved in a flexible way; and (3) build a collaborative consortium where researchers are incentivized to contribute data by giving them priority access and the opportunity to work on exciting questions in group papers. Finally, and more idealistically, the goal was to establish a culture of modern data management and data analysis in sedimentary geochemistry. Relative to many other fields, the main emphasis in our field has been on instrument measurement of sedimentary geochemical data rather than data analysis (compared with fields like ecology, for instance, where the post-experiment ANOVA (analysis of variance) is customary). Thus, the longer-term goal was to build a collaborative environment where geobiologists and geologists can work and learn together to assess changes in geochemical signatures through Earth history.
    Description: We thank the donors of The American Chemical Society Petroleum Research Fund for partial support of SGP website development (61017-ND2). EAS is funded by National Science Foundation grant (NSF) EAR-1922966. BGS authors (JE, PW) publish with permission of the Executive Director of the British Geological Survey, UKRI.
    Keywords: Consortium ; Database ; Earth history ; Geochemistry ; Website
    Repository Name: Woods Hole Open Access Server
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  • 54
    Publication Date: 2022-10-20
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Umanzor, S., Li, Y., Bailey, D., Augyte, S., Huang, M., Marty-Rivera, M., Jannink, J., Yarish, C., & Lindell, S. Comparative analysis of morphometric traits of farmed sugar kelp and skinny kelp, Saccharina spp., strains from the Northwest Atlantic. Journal of the World Aquaculture Society, (2021), https://doi.org/10.1111/jwas.12783.
    Description: Our team has initiated a selective breeding program for regional strains of sugar kelp, Saccharina latissima, to improve the competitiveness of kelp farming in the United States. Within our breeding program, we also include an endemic putative species, Saccharina angustissima, locally referred to as skinny kelp. We crossed uniclonal gametophyte cultures derived from 37 wild‐collected blades representing five sugar kelp strains and one skinny kelp strain to produce 104 unique crosses. Each cross was outplanted on a near‐shore research farm located in the Gulf of Maine (GOM). After the first farming season, our results indicated that sugar kelp and skinny kelp were interfertile, and produced mature and reproductively viable sporophytes. Morphological traits of individual blades varied depending on the parental contribution (sugar vs. skinny), with significant differences found in progeny blade length, width, thickness, and in stipe length and diameter. Despite these differences, wet weight and blade density per plot showed no statistical differences regardless of the cross. Given their published genetic similarity and their interfertility shown here, S. angustissima and S. latissima may not be different species, and may each contribute genetic diversity to breeding programs aimed at meeting ocean farming and market needs.
    Description: Funding was provided by the U.S. Department of Energy, ARPAe MARINER project contract number DE‐AR0000915 and DE‐AR0000911, AgCore Technologies of Rhode Island, and the Massachusetts Clean Energy Center, AmplifyMass Program.
    Keywords: Morphometrics ; Phenotyping ; Saccharina angustissima ; Saccharina latissima ; Seaweed aquaculture ; Selective breeding
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  • 55
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: Oceanic fronts at the mesoscale and submesoscale are associated with enhanced vertical motion, which strengthens their role in global biogeochemical cycling as hotspots of primary production and subduction of carbon from the surface to the interior. Using process study models, theory, and field observations of biogeochemical tracers, this thesis improves understanding of submesoscale vertical tracer fluxes and their influence on carbon cycling. Unlike buoyancy, vertical transport of biogeochemical tracers can occur both due to the movement of isopycnals and due to motion along sloping isopycnals. We decompose the vertical velocity below the mixed layer into two components in a Lagrangian frame: vertical velocity along sloping isopycnal surfaces and the adiabatic vertical velocity of isopycnal surfaces and demonstrate that vertical motion along isopycnal surfaces is particularly important at submesoscales (1-10 km). The vertical flux of nutrient, and consequently the new production of phytoplankton depends not just on the vertical velocity but on the relative time scales of vertical transport and nutrient uptake. Vertical nutrient flux is maximum when the biological timescale of phytoplankton growth matches the vertical velocity frequency. Export of organic matter from the surface and the interior requires water parcels to cross the mixed layer base. Using Lagrangian analysis, we study the dynamics of this process and demonstrate that geostrophic and ageostrophic frontogenesis drive subduction along density surfaces across the mixed layer base. Along-front variability is an important factor in subduction. Both the physical and biological modeling studies described above are used to interpret observations from three research cruises in the Western Mediterranean. We sample intrusions of high chlorophyll and particulate organic carbon below the euphotic zone that are advected downward by 100 meters on timescales of days to weeks. We characterize the community composition in these subsurface intrusions at a lateral resolution of 1–10 km. We observe systematic changes in community composition due to the changing light environment and differential decay of the phytoplankton communities in low-light environments, along with mixing. We conclude that advective fluxes could make a contribution to carbon export in subtropical gyres that is equal to the sinking flux.
    Description: The work in this dissertation was funded by a NDSEG fellowship, Martin Fellowship, Grassle fellowship, Montrym grant, WHOI Academic Programs Office, and Office of Naval Research CALYPSO DRI grant N00014-16-1-3130.
    Keywords: Vertical velocity ; Submesoscale dynamics ; Biophysical interactions
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  • 56
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Master of Science in Mechanical Engineering at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: Operations in the Arctic Ocean are increasingly important due to the changing environment and the resulting global implications. These changes range from the availability of new global trade routes, accessibility of newly available resources in the area, and national security interests of the United States in the region. It’s necessary to build a greater understanding of the undersea environment and how it’s changing since these environmental changes have a direct impact on adjusting future operations in the region and looming global changes as less Arctic ice is present. The recent presence of the Beaufort Lens is changing the acoustic propagation paths throughout the Arctic region. Here a network of buoys were employed to communicate with an Autonomous Undersea Vehicle (AUV) while it operated under the ice throughout the Beaufort Lens with the goal of achieving near GPS quality navigation. The acoustic communications paths were compared using a vertical array throughout the Beaufort Lens. This beam forming was compared to the prediction from BELLHOP. As well, since acoustic communications are affected by multi-path, attenuation and interference from other sources it was interesting to note that bottom bounce was sometimes a reliable acoustic path.
    Keywords: Arctic ; Beaufort Lens ; Acoustic communications
    Repository Name: Woods Hole Open Access Server
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  • 57
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: Chromium (Cr) isotopes have shown great potential as a paleo-redox proxy to trace the redox conditions of ancient oceans and atmosphere. However, its cycling in modern environments is poorly constrained. In my thesis, I attempt to fill in the gap of our understanding of chromium cycling in the modern ocean, with a focus on the redox processes in global oxygen deficient zones (ODZs). Firstly, we developed a method to analyze Cr isotopes of different Cr redox species. Tests on processing conditions demonstrated its robustness in obtaining accurate Cr isotope data. It is applicable to both frozen and fresh samples. This method allows us to investigate the redox cycling of Cr that is hard to unravel by existing total Cr methods. Secondly, in the Eastern Tropical North Pacific (ETNP), Eastern Tropical South Pacific (ETSP) and Arabian Sea ODZs, their total dissolved Cr profiles show preferential reduction of isotopically light Cr(VI) to Cr(III), which is scavenged and exported to deeper oceans. Applying our new method to ETNP and ETSP ODZ seawater samples, we observed Cr(VI) reduction in both ODZs with a similar fractionation factor. This indicates similar mechanisms may be controlling Cr(VI) reduction in the two ODZs. Cr(III) maximum coincides with Fe(II) and secondary nitrite maximums in the upper core of both ODZs. Shipboard incubations with spiked Fe(II) showed fast Cr(VI) reduction occurring in the ETNP ODZ. But neither Fe(II) nor microbes were reducing Cr(VI) directly. Thirdly, we calculated the isotope effects of Cr scavenging in the ETNP and ETSP ODZs. Thetwo ODZs show a similar isotope partitioning during Cr scavenging. And spatial variability is observed in the ETNP ODZ. Our calculated scavenged Cr isotope ratio is lighter than that of the total dissolved Cr from the same depth. It is also comparable to that of reducing or anoxic sediments, which implies that Cr isotopes can be used as an archive for local redox conditions.
    Description: This research was supported by an anonymous MIT Fellowship, Praceis Presidential Fellowship, Frederick A. Middleton Fellowship, the US National Science Foundation (NSF Award No. OCE-1459287, OCE-1736996, OCE-1924050 and DEB-1542240) and the Center for Microbial Oceanography: Research and Education (C-MORE, NSF-OIA Award No. EF-0424599).
    Keywords: Chromium isotopes ; Oxygen deficient zones ; Redox cycling
    Repository Name: Woods Hole Open Access Server
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  • 58
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2022.
    Description: Detection, classification, localization, and tracking (DCLT) of unmanned underwater vehicles (UUVs) in the presence of shipping traffic is a critical task for passive acoustic harbor security systems. In general, vessels can be tracked by their unique acoustic signature due to machinery vibration and cavitation noise. However, cavitation noise of UUVs is considerably quieter than ships and boats, making detection significantly more challenging. In this thesis, I demonstrated that it is possible to passively track a UUV from its highfrequency motor noise using a stationary array in shallow-water experiments with passing boats. First, causes of high frequency tones were determined through direct measurements of two UUVs at a range of speeds. From this analysis, common and dominant features of noise were established: strong tones at the motor’s pulse-width modulated frequency and its harmonics. From the unique acoustic signature of the motor, I derived a high-precision, remote sensing method for estimating propeller rotation rate. In shallow-water UUV field experiments, I demonstrated that detecting a UUV from motor noise, in comparison to broadband noise from the vehicle, reduces false alarms from 45% to 8.4% for 90% true detections. Beamforming on the motor noise, in comparison to broadband noise, improved the bearing accuracy by a factor of 3.2×. Because the signal is also high-frequency, the Doppler effect on motor noise is observable and I demonstrate that range rate can be measured. Furthermore, measuring motor noise was a superior method to the “detection of envelope modulation on noise” algorithm for estimating the propeller rotation rate. Extrapolating multiple measurements from the motor signature is significant because Bearing-Doppler-RPM measurements outperform traditional bearing-Doppler target motion analysis. In the unscented Kalman filter implementation, the tracking solution accuracy for bearing, bearing rate, range, and range rate improved by a factor 2.2×, 15.8×, 3.1×, and 6.2× respectively. These findings are significant for improving UUV localization and tracking, and for informing the next-generation of quiet UUV propulsion systems.
    Keywords: Autonomy ; Passive sonar ; Tracking
    Repository Name: Woods Hole Open Access Server
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  • 59
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Oceanography at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2021.
    Description: The existence of a marine phosphorus (P) redox cycle was recently confirmed when phosphonates, organophosphorus compounds with P in the (III) oxidation state, were found in high molecular weight dissolved organic matter. Although some features of the P redox cycle have come to light since the discovery of phosphonates, many aspects of phosphonate production, cycling and fate remain unknown. To address these gaps in our understanding, we studied phosphonate cycling in the Eastern Mediterranean Sea, a chronically P-limited basin, using 33P and enzymatic assays. We showed that phosphonate production was low but consumption was high, suggesting that phosphonate production and consumption may be spatially or temporally decoupled. We also explored phosphonate production in the model marine cyanobacterium Prochlorococcus SB. Using 31P NMR, we found Prochlorococcus SB allocates ~50% of its cellular P to phosphonates. Allocation of P to phosphonates was conserved under P-limitation, and further investigation revealed phosphonates were associated with proteins. The discovery of phosphonoproteins in Prochlorococcus SB opens new perspectives on the biochemical function of phosphonates and their role in P-cycling. Finally, we developed a new P-targeted method to characterize marine organophosphorus compounds using liquid chromatography coupled to electrospray ionization and inductively coupled plasma mass spectrometry.
    Description: This work was supported by the Simons Foundation under grant numbers POP49476 and 721227 [D. Repeta], the Gordon and Betty Moore Foundation under the grant number 6000 [D. Repeta] and the National Science Foundation OCE under the grant number 1634080 [D. Repeta].
    Keywords: Phosphorus ; Phosphonate ; Biogeochemical cycling
    Repository Name: Woods Hole Open Access Server
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  • 60
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Geophysics at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: This thesis focuses on interpreting geophysical and geochemical observables in terms of the thermomechanical state of the lithosphere. In Chapter 1, I correlate lower crustal rheology with seismic wave speed. Compositional variation is required to explain half of the total variability in predicted lower crustal stress, implying that constraining regional lithology is important for lower crustal geodynamics. In Chapter 2, I utilize thermobarometry, diffusion models, and thermodynamic modelling to constrain the ultra-high formation conditions and cooling rates of the Gore Mountain Garnet Amphibolite in order to understand the rheology of the lower crust during orogenic collapse. In Chapter 3, I interpret geophysical data along a 74 Myr transect in the Atlantic to the temporal variability and relationship of crustal thickness and normal faults. In Chapter 4, I constrain the error present in the forward-calculation of seismic wave speed from ultramafic bulk composition. I also present a database and toolbox to interpret seismic wave speeds in terms of temperature and composition. Finally, in Chapter 5 I apply the methodology from Chapter 4 to interpret a new seismic tomographic model in terms of temperature, density, and composition in order to show that the shallow lithospheric roots are density unstable.
    Description: Funding for this research was provided by an MIT Presidential Fellowship, MIT Student Research Funds, the National Science Foundation Division of Earth Sciences (EAR) and Ocean Sciences (OCE) grants EAR-16-24109, EAR-17-22932, EAR-17-22935, OCE-14-58201, and SCEC Awards 16106 and 17202., SCEC, Geological Society of America Graduate Student Research Fellowship, WHOI Ocean Venture Fund, and the WHOI Academic Programs Office.
    Keywords: Lithosphere ; Seismic wave speed ; Rheology
    Repository Name: Woods Hole Open Access Server
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  • 61
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2021.
    Description: Observations of hydrographic and dynamical properties on the Middle Atlantic Bight shelf document strong variability at time scales spanning events that last a few days to century long trends. This thesis studies individual processes which impact shelf temperature and velocity structure, and quantifies the mean velocity conditions at the shelf break. Chapter 2 uses model output to study the dynamics that lead to the breakdown of summertime thermal stratification, and how the processes which reduce stratification vary from year to year. In summer, the atmosphere heats the surface of the ocean, leading to strong thermal stratification with warm water overlying cool water. During fall, strong storm events with downwelling-favorable winds are found to be the primary process by which stratification is reduced. The timing of these events and the associated destratification varies from year to year. In Chapter 3, the velocity structure of the New Jersey shelf break is examine, with a focus on the Shelfbreak Jet. Using 25 years of velocity measurements, mean velocity sections of the Shelfbreak Jet are created in both Eulerian and stream coordinate frameworks. The jet exhibits strong seasonal variability, with maximum velocities observed in spring and minimum velocities in summer. Evidence is found that Warm Core Rings, originating from the Gulf Stream and passing through the Slope Sea adjacent to the New Jersey shelf, tend to shift the Shelfbreak Jet onshore of its mean position or entirely shutdown the Shelfbreak Jet’s flow. At interannual timescales, variability in the Shelfbreak Jet velocity is correlated with the temperature on the New Jersey Shelf, with temperature lagging by about 2 months. Chapter 4 focuses on the impact of Warm Core Rings on the velocity and temperature structure on the New Jersey shelf. Warm Core Rings that have higher azimuthal velocities and whose cores approach closer to the shelf are found to exert greater influence on the shelf’s along-shelf velocities, with the fastest and closest rings reversing the direction of flow at the shelf break. Warm Core Rings are also observed to exert long-lasting impacts on the shelf temperature, with faster rings cooling the shelf and slower rings warming the shelf. Seasonal changes in thermal stratification strongly affect how rings alter the shelf temperature. Rings in summer tend to cool the shelf, and rings throughout the rest of the year generally warm the shelf.
    Description: This research was funded under WHOI Academic Programs Endowed Funds, NSF #OCE-1634094, and NSF #OCE-1924041.
    Keywords: Temperature variability ; Velocity variability ; Middle Atlantic Bight
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  • 62
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: Small pelagic fishes, also termed forage fishes, represent a critical link between secondary production and myriad top predators in marine ecosystems, including the Northeast US shelf. In this dissertation, I analyze the drivers of forage fish distribution throughout the Northeast US shelf and the drivers of the abundance of the ecologically important northern sand lance. Chapter 2 examines the basic ecology of northern sand lance and uses these insights to identify mechanistic drivers of their abundance. I then explore different scenarios of these drivers to project sand lance abundance through the end of the 21st century, which appears precarious for adult sand lance unless current trajectories change. Chapter 3 analyzes the environmental drivers of the distribution of the six dominant, offshore forage fish species (northern sand lance, Atlantic herring, alewife, blueback herring, Atlantic mackerel, and Atlantic butterfish) on the Northeast US shelf to elucidate the role of environmental covariates in shelf occupancy by these taxa. The results of this chapter indicate shelf occupancy of butterfish and Atlantic mackerel are increasing through time while occupancy of sand lance is decreasing with time. The occurrence of most of these species is also moving deeper and northward with time. Chapter 4 assesses the source-sink dynamics of three sand lance hotspots through Lagrangian particle tracking models simulating larval sand lance transport. Connectivity varies among these hotspots with Georges Bank and Stellwagen Bank having notable retention while the Great South Channel relies on larvae from other hotspots. Retention on Stellwagen Bank and Georges Bank are linked to strong wind events during the larval period of sand lance. Collectively, this dissertation improves our understanding of the dynamics driving variability in the Northeast US shelf forage fish complex, particularly for northern sand lance.
    Description: The research within this dissertation was funded by a National Science Foundation Graduate Research Fellowship (awarded to JJS), Woods Hole Sea Grant (NA18OAR4170104, Project No. R/O-57), the Bureau of Ocean Energy Management (IA agreement M17PG0019), and the National Marine Sanctuary Foundation.
    Keywords: Forage fish ; Northwest Atlantic ; Fisheries oceanography
    Repository Name: Woods Hole Open Access Server
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  • 63
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: An emerging paradigm posits that the abyssal overturning circulation is driven by bottom-enhanced mixing, which results in vigorous upwelling in the bottom boundary layer (BBL) along the sloping seafloor and downwelling in the stratified mixing layer (SML) above; their residual is the overturning circulation. This boundary-controlled circulation fundamentally alters abyssal tracer distributions, with implications for global climate. Chapter 1 describes how a basin-scale overturning circulation arises from the coupling between the ocean interior and mixing-driven boundary layers over rough topography, such as the sloping flanks of mid-ocean ridges. BBL upwelling is well predicted by boundary layer theory, whereas the compensation by SML downwelling is weakened by the upward increase of the basin-wide stratification, which supports a finite net overturning. These simulated watermass transformations are comparable to best-estimate diagnostics but are sustained by a crude parameterization of boundary layer restratification processes. In Chapter 2, I run a realistic simulation of a fracture zone canyon in the Brazil Basin to decipher the non-linear dynamics of abyssal mixing layers and their interactions with rough topography. Using a hierarchy of progressively idealized simulations, I identify three physical processes that set the stratification of abyssal mixing layers (in addition to the weak buoyancy-driven cross-slope circulation): submesoscale baroclinic eddies on the ridge flanks, enhanced up-canyon flow due to inhibition of the cross-canyon thermal wind, and homogenization of canyon troughs below the level of blocking sills. Combined, these processes maintain a sufficiently large near-boundary stratification for mixing to drive globally significant BBL upwelling. In Chapter 3, simulated Tracer Release Experiments illustrate how passive tracers are mixed, stirred, and advected in abyssal mixing layers. Exact diagnostics reveal that while a tracer’s diapycnal motion is directly proportional to the mean divergence of mixing rates, its diapycnal spreading depends on both the mean mixing rate and an additional non-linear stretching term. These simulations suggest that the theorized boundary-layer control on the abyssal circulation is falsifiable: downwelling in the SML has already been confirmed by the Brazil Basin Tracer Release Experiment, while an upcoming experiment in the Rockall Trough will confirm or deny the existence of upwelling in the BBL.
    Description: This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 174530. I also acknowledge funding support from National Science Foundation Awards OCE-1536515 and OCE-1736109. This work was partially supported by MIT’s Rosenblith Presidential Fellowship.
    Keywords: Abyss ; Circulation ; Mixing
    Repository Name: Woods Hole Open Access Server
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  • 64
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biological Oceanography at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: Sound is utilized by marine animal taxa for many ecologically important functions, and these taxa are vulnerable to adverse effects of anthropogenic noise on hearing and behavior. However, little is known about marine invertebrates’ responses to anthropogenic noise, and the ambient environmental sounds (“soundscapes”) they detect and respond to. Most acoustic studies report sound pressure (detected by mammals and some fish), but few report particle motion, the back-and-forth vibratory component of sound detected by marine invertebrates. I investigated invertebrate use of and response to sounds in two facets: 1) behavioral responses of longfin squid, Doryteuthis pealeii to anthropogenic noise, and 2) particle motion of coral reef soundscapes in the U.S. Virgin Islands. In laboratory-based experiments I exposed D. pealeii to construction noise originally recorded from an offshore wind farm. I found significant increases in squids’ alarm responses and in failed prey capture attempts during noise. Conversely, noise exposure had no significant effects on reproductive behaviors of groups of D. pealeii, indicating high motivation of these squid to reproduce during this stressor. Collectively, these experiments revealed the importance of considering behavioral context in studies and regulatory decisions regarding invertebrates’ susceptibility to anthropogenic noise impacts. In studying coral reef soundscapes, I reported particle motion trends over several months for coral reefs varying in habitat quality, including coral cover and fish abundance. I found acoustic properties over which particle motion closely scaled with pressure, and others over which it did not. I compared soundscape data with particle motion hearing thresholds, and found that invertebrates may only detect high amplitude and low frequency transient sound cues on reefs, such as those produced by fishes. My research bring new insights on natural and anthropogenic sound cues detectable by marine invertebrates, and how and when invertebrates will be vulnerable to anthropogenic noise pollution.
    Description: My graduate work was funded in part by the US Department of Interior, Bureau of Ocean Energy Management Environmental Studies Program through Interagency Agreement Number M17PG00029 with the U.S. Department of Commerce, National Oceanic and Atmospheric Administration (funding to Aran Mooney and Jenni Stanley). My work was also supported by the NSF Biological Oceanography award OCE-1536782 (funding to Aran Mooney). I received tuition and stipend support from the National Science Foundation Graduate Research Fellowship Program [Grant No. 2388357]. The Academic Program Office at the Woods Hole Oceanographic Institution provided tuition and stipend support as well as travel support. The MIT Student Assistance Fund, the Aquatic Noise 2019 Organizing Committee, and the Acoustical Society of America also provided travel support.
    Keywords: Cephalopod ; Renewable energy ; Ecoacoustics
    Repository Name: Woods Hole Open Access Server
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  • 65
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Master of Science in Mechanical Engineering at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: A novel performance metric to improve underwater digital acoustic communication, called Multipath Penalty (MPP), is proposed as an alternative to traditional signal-to-noise ratio (SNR) methods in the context of the Arctic Beaufort Sea. MPP and SNR are compared alongside a third performance metric, Minimum Achievable Error (MAE), which replicates the operation of a channel estimate-based decision feedback equalizer in an acoustic modem. The three metrics are then tested in a hardware-in-the-loop Virtual Ocean simulator for an autonomous undersea vehicle (AUV) communicating with a collaborator. Using field data of modem statistics obtained duringICEX20 and expanded data supplied by the simulator, calibration of the three metrics to modem packet success is evaluated, resulting in a proposed recalibration for MAE. The AUV’s ability to communicate when adaptively choosing its depth is analyzed above and below the Beaufort Lens, and settings for MPP’s engineering variables are obtained. The results show MPP generally improves reception and demodulation of acoustic transmissions over SNR by approximately 5% within an operational range of 8 km, while achieving similar results to the more robust metric MAE. MPP is an improved utility for underwater digital acoustic communication in both marine autonomy and as a tactical decision aid.
    Description: This work would not be possible without the extraordinary support of the United States Navy, which provided funding for this research, my degree, and my livelihood as an active duty submarine officer.
    Keywords: Multi-path Penalty ; Acoustics ; Metric
    Repository Name: Woods Hole Open Access Server
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  • 66
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Master of Science in Mechanical Engineering at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: There are many significant challenges for unmanned autonomous platforms at sea including predicting the likely scenarios for the ocean environment, quantifying regional uncertainties, and updating forecasts of the evolving dynamics using their observations. Due to the operational constraints such as onboard power, memory, bandwidth, and space limitations, efficient adaptive reduced order models (ROMs) are needed for onboard predictions. In the first part, several reduced order modeling schemes for regional ocean forecasting onboard autonomous platforms at sea are described, investigated, and evaluated. We find that Dynamic Mode Decomposition (DMD), a data-driven dimensionality reduction algorithm, can be used for accurate predictions for short periods in ocean environments. We evaluate DMD methods for ocean PE simulations by comparing and testing several schemes including domain splitting, adjusting training size, and utilizing 3D inputs. Three new approaches that combine uncertainty with DMD are also investigated and found to produce practical and accurate results, especially if we employ either an ensemble of DMD forecasts or the DMD of an ensemble of forecasts. We also demonstrate some results from projecting / compressing high-fidelity forecasts using schemes such as POD projection and K-SVD for sparse representation due to showing promise for distributing forecasts efficiently to remote vehicles. In the second part, we combine DMD methods with the GMM-DO filter to produce DMD forecasts with Bayesian data assimilation that can quickly and efficiently be computed onboard an autonomous platform. We compare the accuracy of our results to traditional DMD forecasts and DMD with Ensemble Kalman Filter (EnKF) forecast results and show that in Root Mean Square Error (RMSE) sense as well as error field sense, that the DMD with GMM-DO errors are smaller and the errors grow slower in time than the other mentioned schemes. We also showcase the DMD of the ensemble method with GMM-DO. We conclude that due to its accurate and computationally efficient results, it could be readily applied onboard autonomous platforms. Overall, our contributions developed and integrated stochastic DMD forecasts and efficient Bayesian GMM-DO updates of the DMD state and parameters, learning from the limited gappy observation data sets.
    Description: I wish to thank the U.S. Navy’s Civilian Institution Program along with the MITWHOI Joint Program for providing the funding and resources that made this research and continuing my education possible.
    Keywords: Data assimilation ; Reduced order models ; Stochastic prediction
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  • 67
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: The Beaufort Gyre region of the Arctic Ocean is strongly stratified at the base of the wintertime mixed layer, which impedes the vertical transport of heat, energy, and other tracers. Ice-Tethered Profiler observations during 2004-2018 were used to characterize and investigate the seasonal and interannual variability of the strength, depth, density, and thickness of this highly stratified layer at the base of the mixed layer. This includes investigating the remnant stratification maximum, which formed when the summer mixed layer shoaled. Seasonally, the stratification maximum was never in a steady state. It was largest in October (4.8 × 10−3 rad2/sec2) and decreased during all winter months (to 2.3 × 10−3rad2/sec2 in June), indicating that surface forcing and interior vertical mixing were never in equilibrium during the year. Interannually, the period from 2011-2018 had a higher stratification maximum than then the period from 2005-2010 regardless of the season. The remnant stratification maximum was consistently weaker than the winter stratification maximum from which it formed. The initial evolution of the remnant stratification maximum is used to estimate an effective vertical diffusivity of order 10−6m2/s. No significant geographic variability was found, in part due to high temporal and small scale variability of the stratification maximum layer. Implications for heat transport through to the sea ice cover are discussed.
    Keywords: Beaufort Gyre ; Stratification ; Remnant layer
    Repository Name: Woods Hole Open Access Server
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  • 68
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biological Oceanography at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2022.
    Description: Protists are taxonomically and metabolically diverse drivers of energy and nutrient flow in the marine environment, with recent research suggesting significant roles in global carbon cycling throughout the water column. Top-down controls on planktonic protists include grazing and parasitism, processes that both contribute to nutrient transfer and biogeochemical cycling in the global ocean. Recent global surveys of eukaryotic small subunit ribosomal RNA molecular signatures have highlighted the fact that parasites belonging to the marine alveolate order Syndiniales are both abundant and ubiquitous in coastal and open ocean environments, suggesting a major role for this taxon in marine food webs. Two coastal sites, Saanich Inlet (Vancouver Island, BC) and Salt Pond (Falmouth, MA, USA) were selected as model ecosystems to examine the impacts of Syndinian parasitism on protist communities. Data presented in this thesis combines high-resolution sampling, water chemistry (including nutrients) analyses, molecular marker gene analyses, fluorescence in situ hybridization, and modeling to address key knowledge gaps regarding syndinian ecology. Information is presented on previously undescribed putative host taxa, the prevalence of syndinian parasites and infections on different hosts in coastal waters, and a framework for modeling host-parasite interactions based on field observations.
    Description: Research was supported by the WHOI Ocean Venture Fund, the National Science Foundation Biological Oceanography OCE-1851012, and the National Science Foundation Graduate Research Fellowship under Grant No. 1745302.
    Keywords: Syndiniales ; Parasitism ; Protist
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  • 69
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2022.
    Description: The ventilation of intermediate waters in the Labrador Sea has important implications for the strength of the Atlantic Meridional Overturning Circulation. Boundary current-interior interactions regulate the exchange of properties between the slope and the basin, which in turn regulates the magnitude of interior convection and the export of ventilated waters from the subpolar gyre. This thesis characterizes theWest Greenland Boundary Current System near Cape Farewell across a range of spatio-temporal scales. The boundary current system is composed of three velocity cores: (1) the West Greenland Coastal Current (WGCC), transporting Greenland and Arctic meltwaters on the shelf; (2) the West Greenland Current (WGC), which advects warm, saline Atlantic-origin water at depth, meltwaters at the surface, and newly-ventilated Labrador Sea Water (LSW); and (3) the Deep Western Boundary Current, which carries dense overflow waters ventilated in the Nordic Seas. The seasonal presence of the LSW and Atlantic-origin water are dictated by air-sea buoyancy forcing, while the seasonality of the WGCC is governed by remote wind forcing and the propagation of coastally trapped waves from East Greenland. Using mooring data and hydrographic surveys, we demonstrate mid-depth intensified cyclones generated at Denmark Strait are found offshore of the WGC and enhance the overflow water transport at synoptic timescales. Using mooring, hydrographic, and satellite data, we demonstrate that the WGC undergoes extensive meandering due to baroclinic instability that is enhanced in winter due to LSW formation adjacent to the current. This leads to the production of small-scale, anticyclonic eddies that can account for the entirety of wintertime heat loss within the Labrador Sea. The meanders are shown to trigger the formation of Irminger Rings downstream. Using mooring, hydrographic, atmospheric, and Lagrangian data, and a mixing model, we find that strong atmospheric storms known as forward tip jets cause upwelling at the shelfbreak that triggers offshore export of freshwater. This freshwater flux can explain the observed lack of ventilation in the eastern Labrador Sea. Together, this thesis documents previously unobserved interannual, seasonal, and synoptic-scale variability and dynamics within the West Greenland boundary current system that must be accounted for in future modeling.
    Description: The work in this dissertation was funded by the National Science Foundation grants OCE-1259618 and OCE-1756361.
    Keywords: Boundary current dynamics ; Labrador sea water formation ; Eddies
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  • 70
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2021.
    Description: Subduction zones host the greatest earthquakes on earth and pose great threat to human society. The largest slip in megathrust earthquakes often occurs in the 10–50 km depth range, yet seismic imaging of the material properties in this region has proven difficult. This thesis focuses on developing methods to utilize high frequency (2–12 Hz) seismic waves scattered from the megathrust plate interface to constrain its fine-scale velocity structures and to investigate the relationship between velocity structures and megathrust slip behaviors. Chapter 2 investigates the locking condition of the subducted Gorda plate by simulating afterslip that would be expected as a result of the stress changes from offshore strike-slip earthquakes. Chapter 3 develops array analysis methods to identify P-to-S and S-to-P seismic converted phases that convert at the subducted Gorda plate interface from local earthquakes and uses them to constrain the geometry and material properties of the plate boundary fault of the subducted Gorda plate between 5–20 km depth. Chapters 4 and 5 use a dense nodal array and numerical modeling methods to study the seismic guided waves that propagate along the thin low velocity layer at the boundary of the subducted Gorda plate. Taken together, our results indicate that material properties of the subduction plateboundary fault is highly heterogeneous and the plate-boundary fault is potentially contained in a low velocity layer with significant porosity and fluid content at seismogenic depths.
    Description: Funding for this research was provided by National Science Foundation Division of Earth Sciences (EAR) award #1520690 and the WHOI Academic Programs Office.
    Keywords: Subduction zone ; Scattered seismic waves ; Plate boundary
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  • 71
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Oceanography at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2021.
    Description: Anthropogenic emissions of greenhouse gases are driving rapid changes in ocean conditions. Shallow-water coral reefs are experiencing the brunt of these changes, including intensifying marine heatwaves (MHWs) and rapid ocean acidification (OA). Consequently, coral reefs are in broad-scale decline, threatening the livelihoods of hundreds of millions of people. Ensuring survival of coral reefs in the 21st century will thus require a new management approach that incorporates robust understanding of reef-scale climate change, the mechanisms by which these changes impact corals, and their potential for adaptation. In this thesis, I extract information from within coral skeletons to 1) Quantify the climate changes occurring on coral reefs and the effects on coral growth, 2) Identify differences in the sensitivity of coral reefs to these changes, and 3) Evaluate the adaptation potential of the keystone reef-building coral, Porites. First, I develop a mechanistic Porites growth model and reveal the physicochemical link between OA and skeletal formation. I show that the thickening (densification) of coral skeletal framework is most vulnerable to OA and that, under 21st century climate model projections, OA will reduce Porites skeletal density globally, with greatest impact in the Coral Triangle. Second, I develop an improved metric of thermal stress, and use a skeletal bleaching proxy to quantify coral responses to intensifying heatwaves in the central equatorial Pacific (CEP) since 1982. My work reveals a long history of bleaching in the CEP, and reef-specific differences in thermal tolerance linked to past heatwave exposure implying that, over time, reef communities have adapted to tolerate their unique thermal regimes. Third, I refine the Sr-U paleo-thermometer to enable monthly-resolved sea surface temperatures (SST) generation using laser ablation ICPMS. I show that laser Sr-U accurately captures CEP SST, including the frequency and amplitude of MHWs. Finally, I apply laser Sr-U to reconstruct the past 100 years of SST at Jarvis Island in the CEP, and evaluate my proxy record of bleaching severity in this context. I determine that Porites coral populations on Jarvis Island have not yet adapted to the pace of anthropogenic climate change.
    Description: This research was supported by US National Science Foundation Awards OCE-1220529, ANT-1246387, OCE-1737311, CE-1601365, OCE-1805618, OCE-1537338, OCE-2016133, and from the Woods Hole Oceanographic Institution through the Ocean Life Institute, the Ocean Ventures Fund, the Grassle Fellowship Fund, and the MIT-WHOI Academic Programs Office. Additional funding was provided by the Taiwan MOST Grant 104-2628-M-001-007-MY3, the Robertson Foundation, the Leverhulme Trust in UK, the Atlantic Donor Advised Fund, The Prince Albert 2 of Monaco Foundation, the Akiko Shiraki Dynner Fund, the New England Aquarium, the Martin Family Society Fellowship for Sustainability, the Gates Millenium Scholarship, the Arthur Vining Davis Foundation, the NOAA Coral Reef Conservation Program, and from the Woods Hole Oceanographic Institution through Investment in Science Fund, the Early Career Award, and the Access to the Sea Award.
    Keywords: Coral reef ; Climate ; Proxy
    Repository Name: Woods Hole Open Access Server
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  • 72
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Master of Science in Physical Oceanography at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2021.
    Description: Estimating turbulence in the marine-atmospheric boundary layer is critical to many industrial, commercial and scientific fields, but of particular importance to the wind energy industry. Contributing to both the efficiency of energy extraction and the life-cycle cost of the turbine itself, turbulence in the atmospheric boundary layer is estimated within the wind energy industry as Turbulence Intensity (TI) and more recently by Turbulent Kinetic Energy (TKE). Traditional in-situ methods to measure turbulence are extremely difficult to deploy in the marine environment, resulting in a recent movement to and dependence on remote sensing methods. One type of remote sensing instrument, Doppler lidars, have shown to reliably estimate the wind speed and atmospheric turbulence while being cost effective and easily deployable, and hence are being increasingly utilized as a standard for wind energy assessments. In this thesis, the ability of lidars to measure turbulence up to a height of 200 m above mean sea level in the marine-atmospheric boundary layer was tested using a 7-month data set spanning winter to early summer. Lidar-based TI and TKE were estimated by three methods using observations from a highly validated lidar system and compared under both convective and stable atmospheric stability conditions. Convective periods were found to have higher turbulence at all the heights compared to stable conditions, while mean wind speed and shear were higher during stable conditions. The study period was characterized by generally low turbulent conditions with high turbulence events occurring at timescales of a few days. Mean vertical profiles of TKE were non-uniformly distributed in height during low turbulent conditions. During highly turbulent events, TKE increased more strongly with height. The definition of TI– following the industry or meteorology conventions – had no real effect on the results, and differences between cup or sonic anemometers and lidar TI values were small except at low wind speeds. All the three lidar-based TKE methods tested corresponded closely to independent estimates, and differences between the methods were small relative to the temporal variability of TKE observed at the offshore site.
    Keywords: Turbulence ; Wind engery ; Lidar
    Repository Name: Woods Hole Open Access Server
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  • 73
    Publication Date: 2022-10-20
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Caruso, F., Hickmott, L., Warren, J. D., Segre, P., Chiang, G., Bahamonde, P., Español-Jiménez, S., Li, S., & Bocconcelli, A. Diel differences in blue whale (Balaenoptera musculus) dive behavior increase nighttime risk of ship strikes in northern Chilean Patagonia. Integrative Zoology, (2020): 1-18, doi:10.1111/1749-4877.12501.
    Description: The northern Chilean Patagonia region is a key feeding ground and a nursing habitat in the southern hemisphere for blue whales (Balaenoptera musculus). From 2014 to 2019, during 6 separate research cruises, the dive behavior of 28 individual blue whales was investigated using bio‐logging tags (DTAGs), generating ≈190 h of data. Whales dove to significantly greater depths during the day compared to nighttime (day: 32.6 ± 18.7 m; night: 6.2 ± 2.7 m; P 〈 0.01). During the night, most time was spent close to the surface (86% ± 9.4%; P 〈 0.01) and at depths of less than 12 m. From 2016 to 2019, active acoustics (scientific echosounders) were used to record prey (euphausiids) density and distribution simultaneously with whale diving data. Tagged whales appeared to perform dives relative to the vertical migration of prey during the day. The association between diurnal prey migration and shallow nighttime dive behavior suggests that blue whales are at increased risk of ship collisions during periods of darkness since the estimated maximum ship draft of vessels operating in the region is also ≈12 m. In recent decades, northern Chilean Patagonia has seen a large increase in marine traffic due to a boom in salmon aquaculture and the passenger ship industry. Vessel strike risks for large whales are likely underestimated in this region. Results reported in this study may be valuable for policy and mitigation decisions regarding conservation of the endangered blue whale.
    Description: This work was conducted under Chilean research permit PINV 38–2014 Ballena Azul, Golfo Corcovado, from the Ministerio de Economia, Fomento y Turismo, Subsecreteria de Pesca y Acuicultura. We would like to thank the crews of the vessels Centinela, Khronos and Solidaridad for their involvement in the fieldwork. Special thanks to Rafaela Landea‐Briones, Gloria Howes, Esteban Tapia Brunet, Pepe Montt, Thomas Montt, and Daniel Casado for helping and welcoming us in Patagonia. Thanks to MERI Foundation and their students Carlos Cantergiani, Andrea Hirmas and Elvira Vergara for their support and contributions to field efforts. We extend our gratitude to our collaborators Laela Sayigh, Michael Moore, Daniel Zitterbart, Frants Jensen, Aran Mooney, John Durban, Jeremy Goldbogen, and Dave Cade. Thanks to WHOI for financial and technical support. The data analysis and paper writing was financially supported by the National Key Research and Development Program of China (Grant number 2016YFC0300802); the biodiversity investigation, observation and assessment program (2019‐2023) of the Ministry of Ecology and Environment of China; and Indian Ocean Ninety‐east Ridge Ecosystem and Marine Environment Monitoring and Protection, supported by the China Ocean Mineral Resources R&D Association (no. DY135‐E2‐4). Additionally, FC thanks the President's International Fellowship Initiative (PIFI) of the Chinese Academy of Sciences.
    Keywords: Bio‐logging tags ; Blue whale ; Diving profile ; Ocean conservation ; Prey distribution
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  • 74
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physical Oceanography at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2021.
    Description: The apparent global increase in harmful algal blooms (HABs) includes Pseudo-nitzschia blooms in the Gulf of Maine, where shellfishery closures can cost millions of dollars. Temperatures in the gulf are warming, which can affect the severity of some HABs. Yet Pseudo-nitzschia in the region are understudied. Pseudo-nitzschia bloom dynamics, P. australis introduction, and potential future changes thereof were investigated in the Gulf of Maine. Data from ship surveys and moorings were used, as well as hydrodynamic, climate, and Lagrangian particle tracking models. Pseudonitzschia bloom toxicity was driven primarily by species composition, not environmental factors. P. australis was introduced to the region in 2016 via a coastal current from the Scotian Shelf. Climate change might intensify Pseudo-nitzschia blooms, shift bloom timing 1–2 weeks earlier in the spring or 4–6 weeks later in the fall, or lengthen the growing season by 3 weeks. It might also affect species composition and connectivity within the gulf. This work has implications for the monitoring of current and future blooms in the Gulf of Maine and for our understanding of HAB introduction to the region. It can also be used to develop predictive models for Pseudo-nitzschia, which could be applied to other HABs.
    Description: This research was funded by the National Science Foundation (Grants OCE-1314642 and OCE-1840381), the National Institute of Environmental Health Sciences (Grants 1P01ES021923-01 and P01 ES028938-01), the Woods Hole Center for Oceans and Human Health, WHOI Academic Programs Funds, the Vannevar Bush Faculty Fellowship, and the National Oceanic and Atmospheric Administration’s HAB Event Response Program (2012 and 2016).
    Keywords: Harmful algal blooms ; Modeling ; Gulf of Maine
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  • 75
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2021.
    Description: The Arctic Ocean is a vital component of Earth’s climate system experiencing dramatic environmental changes. The changes are reflected in its underwater ambient soundscape as its origin and propagation are primarily dependent on properties of the ice cover and water column. The first component of this work examines the effect on ambient noise characteristics due to changes to the Beaufort Sea sound speed profile (SSP) and ice cover. Specifically, the emergence of a warm water intrusion near 70 m depth has altered the historical Arctic SSP while the ice cover has become thinner and younger due to the rise in average global temperature. Hypothesized shifts to the ambient soundscape and surface noise generation due to these changes are verified by comparing the measured noise data during two experiments to modeled results. These changes include a broadside notch in noise vertical directionality as well as a shift from uniform surface noise generation to discrete generation at specific ranges. Motivated by our data analyses, the second component presents several tools to facilitate ambient noise characterization and generation monitoring. One is a convolutional neural network (CNN) approach to noise range estimation. Its robustness to SSP and bottom depth mismatch is compared with conventional matched field processing. We further explore how the CNN approach achieves its performance by examining its intermediate outputs. Another tool is a frequency domain, transient event detection algorithm that leverages image processing and hierarchical clustering to identify and categorize noise transients in data spectrograms. The spectral content retained by this method enables insight into the generation mechanism of the detected events by the ice cover. Lastly, we present the deployment of a seismo-acoustic system to localize transient events. Two forward approaches that utilize time-difference-ofarrival are described and compared with a more conventional, inverse technique. The examination of this system’s performance prompts recommendations for future deployments. With our ambient noise analysis and algorithm development, we hope these contributions provide a stronger foundation for continued study of the Arctic ambient soundscape as the region continues to grow in significance.
    Description: Office of Naval Research (ONR) via the University of California - San Diego (UCSD) under award number N00014-16-1-2129. Defense Advanced Research Projects Agency (DARPA) via Applied Physical Sciences Corp. (APS) under award number HR0011-18-C-0008. Office of Naval Research (ONR) under award number N00014-17-1-2474. Office of Naval Research (ONR) under award number N00014-19-1-2741. National Science Foundation (NSF) under grant number 2389237.
    Keywords: Ambient noise ; Arctic change ; Noise analysis
    Repository Name: Woods Hole Open Access Server
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  • 76
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Oceanographic Engineering at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2021.
    Description: Nearly 1.5 million people inhabit barrier islands along the U.S. Atlantic and Gulf Coasts and coastal groundwater dynamics influence the availability of freshwater, ecosystem health, pollutant transport, and flooding in these densely populated communities. However, groundwater dynamics, including the aquifer head distribution and subsurface salinity structure, in coastal aquifers are affected by multiple environmental forcings, such as waves, tides, storm surges, and precipitation that act on a variety of spatial and temporal scales, making coastal groundwater dynamics complex and difficult to predict. Here, measurements of groundwater heads, salinities, and temperatures collected for 3 years across a 550-m-wide barrier island are used in conjunction with observations of ocean tides, surge, waves, sound level, and rainfall to characterize the dynamics of the surface aquifer. Infiltration from surge, tides, and waves during storms caused up to 2 m increases in the groundwater level under the dune. The head gradients owing to these storm-induced groundwater bulges suggest flows become inland directed on the ocean-side of the island during storms. An upper saline plume (20-30 PSU) was observed above fresher (10 PSU) water up to 30 m inland of the dune face, which was the maximum wave runup location. Differences in inland propagation between tidal- and storm-induced groundwater head fluctuations are explained using analytical theories for intermediate depth aquifers. Additionally, a separate analytical water-table evolution model driven with estimated ocean shoreline water levels (based on the 36-hr-averaged offshore tide, surge, and wave height) and measured precipitation is validated by citizen-science flood reports and predicts the maximum water-table height within 0.1 m of the observed levels across the barrier island.
    Description: Funding for this research was provided by the U.S. Coastal Research Program, the National Science Foundation, a National Science Foundation Graduate Research Fellowship, the Woods Hole Oceanographic ISP program, and National Security Science & Engineering and Vannevar Bush Faculty Fellowships.
    Keywords: Groundwater ; Storms ; Coastal aquifer
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  • 77
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: Autonomous underwater vehicles (AUVs) are an increasingly capable robotic platform, with embedded acoustic sensing to facilitate navigation, communication, and collaboration. The global positioning system (GPS), ubiquitous for air- and terrestrial-based drones, cannot position a submerged AUV. Current methods for acoustic underwater navigation employ a deterministic sound speed to convert recorded travel time into range. In acoustically complex propagation environments, however, accurate navigation is predicated on how the sound speed structure affects propagation. The Arctic’s Beaufort Gyre provides an excellent case study for this relationship via the Beaufort Lens, a recently observed influx of warm Pacific water that forms a widespread yet variable sound speed lens throughout the gyre. At short ranges, the lens intensifies multipath propagation and creates a dramatic shadow zone, deteriorating acoustic communication and navigation performance. The Arctic also poses the additional operational challenge of an ice-covered, GPSdenied environment. This dissertation demonstrates a framework for a physics-based, model-aided, real-time conversion of recorded travel time into range—the first of its kind—which was essential to the successful AUV deployment and recovery in the Beaufort Sea, in March 2020. There are three nominal steps. First, we investigate the spatio-temporal variability of the Beaufort Lens. Second, we design a human-in-the-loop graphical decision-making framework to encode desired sound speed profile information into a lightweight, digital acoustic message for onboard navigation and communication. Lastly, we embed a stochastic, ray-based prediction of the group velocity as a function of extrapolated source and receiver locations. This framework is further validated by transmissions among GPS-aided modem buoys and improved upon to rival GPS accuracy and surpass GPS precision. The Arctic is one of the most sensitive regions to climate change, and as warmer surface temperatures and shrinking sea ice extent continue to deviate from historical conditions, the region will become more accessible and navigable. Underwater robotic platforms to monitor these environmental changes, along with the inevitable rise in human traffic related to trade, fishing, tourism, and military activity, are paramount to coupling national security with international climate security.
    Description: Office of Naval Research (N00014-14-1-0214) — GOATS’14 Adaptive and Collaborative Exploitation of 3-Dimensional Environmental Acoustics in Distributed Undersea Networks Draper Laboratory Incorporated (SC001-0000001039) — Positioning System for Deep Ocean Navigation (POSYDON) Office of Naval Research (N00014-16-1-2129) — MURI: The Information Content of Ocean Noise: Theory and Experiment Office of Naval Research (N00014-17-1-2474) — Environmentally Adaptive Acoustic Communication and Navigation in the New Arctic Office of Naval Research (N00014-19-1-2716) — TFO: Assessing Realism and Uncertainties in Navy Decision Aids Department of Defense, Office of Naval Research — National Defense, Science, and Engineering Graduate Fellowship
    Keywords: Beaufort Lens ; GPS-denied underwater navigation ; Marine robotics
    Repository Name: Woods Hole Open Access Server
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  • 78
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    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Master of Science in Aeronautics and Astronautics at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2021.
    Description: Global temperature rise and increased atmospheric carbon dioxide (CO2) levels have affected the health of the world’s ocean and water ecosystems, impacting the balances of natural carbon cycling and causing ocean acidification. Additionally, as global temperatures rise, thawing permafrost has stimulated increased release of methane (CH4), a gas with a shorter lifetime in the atmosphere but with even more heat trapping ability than CO2. In situ analysis of dissolved gas content in surface waters is currently performed with large, expensive instruments, such as spectrometers, which are coupled with gas equilibration systems, which extract dissolved gas from water and feed it to the sensor. Accurate, low cost, and portable sensors are needed to measure the dissolved CH4 and CO2 concentration in water systems to quantify their release and understand their relationship to the global carbon budget. At the same time, while greenhouse gases are well established threats to water ecosystems, the ubiquity and potential consequences of microplastics in aqueous environments are just beginning to be recognized by the environmental research community. Microplastics (MPs) are small particles of polymer debris, commonly defined as being between 1 μm and 1000 μm. Despite the pervasiveness of MPs, our ability to characterize MPs in the environment is limited by the lack of technologies for rapidly and accurately identifying and quantifying MPs. This thesis is concerned with the engineering challenges prompted by the need for high quality and quantity environmental data to better study and the impact, cycling, and prevalence of these pollutants in aqueous environments. Three distinct investigations are presented here. First, the design of the Low-Cost Gas Extraction and Measurement System (LC-GEMS) for dissolved CO2 is presented. At just under $600 dollar to build, the LC-GEMS is an ultra-portable, toolbox-sized instrument for dissolved gas sensing in near-surface waters. The LCGEMS was characterized in the lab and demonstrated linear relationships with dissolved CO2 as well as temperature. Lab calibrations and subsequent field testing in the Little Sippewissett Marsh, in Falmouth, Massachusetts showed that the LCGEMS captures both diurnal and minute-time scale trends in dissolved CO2. Second, this thesis presents the novel design of three simple and low-cost planar nanophotonic and plasmonic structures as optical transducers for measuring dissolved CH4. Through simulations, the sensitivity of the structures are evaluated and found to exhibit superior performance in the reflectance intensity readout mode to that of the standard surface-plasmon-polariton-mode Spreeta sensor. A practical, small, and low-cost implementation of this chip with a simple intensity-based measurement scheme is proposed. This design is novel in the space of dissolved gas monitoring because it shows potential to measure directly in the water phase while being robust and low-cost to implement. Finally, this thesis presents a literature review and perspective to motivate the development of field-deployable microplastic sensing techniques. A framework for field-deployable microplastic sensing is presented and seeks to inform the MP community of the potential in both traditional MP analysis techniques and unconventional methods for creating rapid and automated MP sensors. The field-deployabilty framework addresses a full scope of practical/technological trade-offs to be considered for portable MP detection.
    Keywords: Dissolved gas ; Microplastics ; Instrumentation
    Repository Name: Woods Hole Open Access Server
    Type: Thesis
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  • 79
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    Unknown
    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: As the western boundary current of the North Atlantic, the Gulf Stream is a well established area of interest for the United States Navy, predominately due to its proximity to the continental shelf and the associated challenges of acoustic propagation across large property gradients. Autonomous underwater gliders conduct routine, high-resolution surveys along the U.S. East Coast, including within the Gulf Stream. These observations are assimilated into the operational Navy Coastal Ocean Model (NCOM). An investigation of the forecast-to-nowcast changes in the model for 2017 demonstrates the impact of the observations on the model. The magnitude of model change as a function of distance from nearest new observation reveals relatively large impact of glider observations within a radius of 𝒪(100) km. Glider observations are associated with larger local impact than Argo data, likely due to glider sampling focusing on large spatial gradients. Due to the advective nature of the Gulf Stream system, the impact of glider observations in the model is anisotropic with larger impacts extending downstream from observation locations. Forecast-to-nowcast changes in modeled temperature, salinity, and density result in improved agreement between observed and modeled ocean structure within the upper 200 m over the 24 hours between successive model runs.
    Description: This research was funded via the United States Navy’s Civilian Institution Program with the Massachusetts Institute of Technology/Woods Hole Oceanographic Institution Joint Program (MIT/WHOI JP). Glider observations and analyses have been generously supported by the National Science Foundation (OCE-0220769, OCE-1558521, OCE-1633911, OCE-1923362), NOAA’s Global Ocean Monitoring and Observing Program (NA14OAR4320158, NA19OAR4320074), the Office of Naval Research (N000141713040), Eastman Chemical Corporation, WHOI’s Oceans and Climate Change Institute, and the W. Van Alan Clark, Jr. Chair for Excellence in Oceanography at WHOI (awarded to Breck Owens).
    Keywords: Model ; Glider ; Gulf Stream
    Repository Name: Woods Hole Open Access Server
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  • 80
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    Unknown
    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: This thesis analyzes data from two types of unique drifter experiments in order to characterize two aspects of ocean flows that are often difficult to study. First, vertical velocities and their associated transport processes are often challenging to observe in the real ocean since vertical velocities are typically orders of magnitude smaller than horizontal velocities in mesoscale and submesoscale flows. Second, Lagrangian coherent structures (LCS) are features which categorize ocean flows into regimes of distinct behavior. These structures are also difficult to quantify in the real ocean, since sets of gridded trajectories from real ocean data (rather than model fields) are rarely available. The first experiment uses drifters drogued at multiple depths in the Alboran Sea to observe and characterize the ocean’s vertical structure, particularly near a strong front where vertical velocities are expected to be much stronger than other regions of the Ocean. The second experiment uses a roughly gridded pattern of surface drifters in the Gulf of Mexico to study LCSs as quantified by methods from dynamical systems such as finitetime Lyapunov exponents (FTLEs), trajectory arc-length, correlation dimension, dilation, Lagrangian-averaged vorticity deviation (LAVD), and spectral clustering. This thesis includes the first attempt to apply these dynamical systems techniques to real drifters for LCS detection. Overall, these experiments and the methods used in this paper are shown to be promising new techniques for quantifying both the vertical structure of ocean flows and Lagrangian Coherent Structures of flows using real drifter data. Future work may involve modified versions of the experiments, with denser sets of ocean drifters in the horizontal and/or vertical directions.
    Description: My Masters studies in the MIT/WHOI Joint Program were funded by the US Navy Civilian Institution Office.
    Keywords: Lagrangian coherent structures ; Finite-time Lyapunov exponents ; Vertical transport
    Repository Name: Woods Hole Open Access Server
    Type: Thesis
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  • 81
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    Unknown
    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-10-20
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Oceanography at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2021.
    Description: Phytoplankton are communities of diverse groups of prokaryotic and eukaryotic single-celled organisms responsible for nearly 50% of global primary production. The relative abundance of individual groups changes dynamically in response to environmental perturbations. Recent studies suggest that such changes are primarily driven by the distinct physiological responses employed by each group towards a particular perturbation. Although knowledge of some of these responses has come to light in recent years, many aspects of their metabolisms remain unknown. We attempt to address this gap by studying the metabolism of several phytoplankton groups using metabolomics. Firstly, we developed a method to enhance the analysis of untargeted metabolomics data. Secondly, we constructed two conceptual models describing how metabolism of the raphidophyte Heterosigma akashiwo responds to phosphorus and nitrogen stress. These conceptual models revealed several new stress response mechanisms not previously reported in other phytoplankton. Finally, we compared the metabolic changes of several distinct phytoplankton groups to uncover possible adaptation and acclimations that distinguish them. This analysis revealed several pathways and metabolites that represent the studied groups. The contributions of these pathways and metabolites towards physiology may support the ecological fitness of these organisms.
    Description: None of this work would have been possible without a variety of funding sources. I was supported for three years by a National Science Foundation Graduate Research Fellowship and one year with a GEM fellowship. The research was carried out with grants from the MIT Microbiome Center (Award ID #6936800, EBK), the Simons Foundation (Award ID #509034, EBK), the Gordon and Betty Moore Foundation (Award ID #3304 EBK), the National Science Foundation (Award ID #OCE-0619608 to EBK and OCE-1057447 to EBK and MCKS) and the WHOI Ocean Ventures Fund.
    Keywords: Phytoplankton ; Metabolism ; Metbolomics
    Repository Name: Woods Hole Open Access Server
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  • 82
    Publication Date: 2022-10-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Patrick, S. C., Martin, J. G. A., Ummenhofer, C. C., Corbeau, A., & Weimerskirch, H. Albatrosses respond adaptively to climate variability by changing variance in a foraging trait. Global Change Biology, (2021), https://doi.org/10.1111/gcb.15735.
    Description: The ability of individuals and populations to adapt to a changing climate is a key determinant of population dynamics. While changes in mean behaviour are well studied, changes in trait variance have been largely ignored, despite being assumed to be crucial for adapting to a changing environment. As the ability to acquire resources is essential to both reproduction and survival, changes in behaviours that maximize resource acquisition should be under selection. Here, using foraging trip duration data collected over 7 years on black-browed albatrosses (Thalassarche melanophris) on the Kerguelen Islands in the southern Indian Ocean, we examined the importance of changes in the mean and variance in foraging behaviour, and the associated effects on fitness, in response to the El Niño Southern Oscillation (ENSO). Using double hierarchical models, we found no evidence that individuals change their mean foraging trip duration in response to a changing environment, but found strong evidence of changes in variance. Younger birds showed greater variability in foraging trip duration in poor conditions as did birds with higher fitness. However, during brooding, birds showed greater variability in foraging behaviour under good conditions, suggesting that optimal conditions allow the alteration between chick provisioning and self-maintenance trips. We found weak correlations between sea surface temperature and the ENSO, but stronger links with sea-level pressure. We suggest that variability in behavioural traits affecting resource acquisition is under selection and offers a mechanism by which individuals can adapt to a changing climate. Studies which look only at effects on mean behaviour may underestimate the effects of climate change and fail to consider variance in traits as a key evolutionary force.
    Description: The authors thank the Institut Polaire Français Paul Emile Victor (IPEV, programme 109 to HW) for providing financial and logistical support for the field work at Kerguelen, and to the Terres Australes et Antarctique Francaises (TAAF). The usage of the following data sets is gratefully acknowledged: SOI, NCEP/NCAR SLP and NOAA OISST v2, all provided by NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, through https://www.esrl.noaa.gov/psd. CCU acknowledges support from the Joint Initiative Awards Fund from the Andrew W. Mellon Foundation and the James E. and Barbara V. Moltz Fellowship for Climate-Related Research.
    Keywords: Bet-hedging ; Intra-individual variability ; Resource acquisition ; Salt-water immersion logger ; Seabirds ; Southern Oscillation Index
    Repository Name: Woods Hole Open Access Server
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  • 83
    Publication Date: 2022-05-27
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Bucklin, A., Peijnenburg, K. T. C. A., Kosobokova, K. N., O'Brien, T. D., Blanco-Bercial, L., Cornils, A., Falkenhaug, T., Hopcroft, R. R., Hosia, A., Laakmann, S., Li, C., Martell, L., Questel, J. M., Wall-Palmer, D., Wang, M., Wiebe, P. H., & Weydmann-Zwolicka, A. Toward a global reference database of COI barcodes for marine zooplankton. Marine Biology, 168(6), (2021): 78, https://doi.org/10.1007/s00227-021-03887-y.
    Description: Characterization of species diversity of zooplankton is key to understanding, assessing, and predicting the function and future of pelagic ecosystems throughout the global ocean. The marine zooplankton assemblage, including only metazoans, is highly diverse and taxonomically complex, with an estimated ~28,000 species of 41 major taxonomic groups. This review provides a comprehensive summary of DNA sequences for the barcode region of mitochondrial cytochrome oxidase I (COI) for identified specimens. The foundation of this summary is the MetaZooGene Barcode Atlas and Database (MZGdb), a new open-access data and metadata portal that is linked to NCBI GenBank and BOLD data repositories. The MZGdb provides enhanced quality control and tools for assembling COI reference sequence databases that are specific to selected taxonomic groups and/or ocean regions, with associated metadata (e.g., collection georeferencing, verification of species identification, molecular protocols), and tools for statistical analysis, mapping, and visualization. To date, over 150,000 COI sequences for ~ 5600 described species of marine metazoan plankton (including holo- and meroplankton) are available via the MZGdb portal. This review uses the MZGdb as a resource for summaries of COI barcode data and metadata for important taxonomic groups of marine zooplankton and selected regions, including the North Atlantic, Arctic, North Pacific, and Southern Oceans. The MZGdb is designed to provide a foundation for analysis of species diversity of marine zooplankton based on DNA barcoding and metabarcoding for assessment of marine ecosystems and rapid detection of the impacts of climate change.
    Description: Funding sources for authors of the review paper are described here: Scientific Committee on Oceanic Research (SCOR), and a grant to SCOR from the U.S. National Science Foundation (OCE-1840868). Netherlands Organization for Scientific Research (NWO) Vidi Grant/Award Number: 016.161.351 to K.T.C.A.P. European Union Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 746186 (POSEIDoN) to D.W.P. The work of K.N.K. was performed in the framework of the state assignment of IO RAS (Theme No. 0128-2021-0007) and partially supported by Russian Foundation for Basic Research grants No. 18-05-60158 and No. 19-04-00955. The work of A.W.Z. was supported by a grant from HIDEA—Hidden diversity of the Arctic Ocean (No. 2017/27/B/NZ8/01056) from the National Science Centre, Poland, and a Fulbright Senior Award. The Norwegian Taxonomy Initiative of the Norwegian Biodiversity Information Centre provided funding for A.H. and L.M. (Project Nos. 70184233/HYPNO and 70184240/NORHYDRO), and for T.F. (Project Nos. 70184233/COPCLAD and 70184241/HYPCOP). The work of R.R.H. and J.M.Q. was supported by Census of Marine Life and NOAA Ocean Exploration and Research (NA05OAR4601079 and NA15OAR0110209). The work of S.L. was conducted at the Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB). HIFMB is a collaboration between the Alfred-Wegener-Institute, Helmholtz-Center for Polar and Marine Research, and the Carl-von-Ossietzky University Oldenburg, initially funded by the Ministry for Science and Culture of Lower Saxony and the Volkswagen Foundation through the Niedersächsisches Vorab’ grant program (Grant No. ZN3285).
    Repository Name: Woods Hole Open Access Server
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  • 84
    Publication Date: 2022-05-27
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Jenouvrier, S., Judy, C.-C., Wolf, S., Holland, M., Labrousse, S., LaRue, M., Wienecke, B., Fretwell, P., Barbraud, C., Greenwald, N., Stroeve, J., & Trathan, P. N. The call of the emperor penguin: legal responses to species threatened by climate change. Global Change Biology, 27, (2021): 5008– 5029, https://doi.org/10.1111/gcb.15806.
    Description: Species extinction risk is accelerating due to anthropogenic climate change, making it urgent to protect vulnerable species through legal frameworks in order to facilitate conservation actions that help mitigate risk. Here, we discuss fundamental concepts for assessing climate change risks to species using the example of the emperor penguin (Aptenodytes forsteri), currently being considered for protection under the US Endangered Species Act (ESA). This species forms colonies on Antarctic sea ice, which is projected to significantly decline due to ongoing greenhouse gas (GHG) emissions. We project the dynamics of all known emperor penguin colonies under different GHG emission scenarios using a climate-dependent meta-population model including the effects of extreme climate events based on the observational satellite record of colonies. Assessments for listing species under the ESA require information about how species resiliency, redundancy and representation (3Rs) will be affected by threats within the foreseeable future. Our results show that if sea ice declines at the rate projected by climate models under current energy system trends and policies, the 3Rs would be dramatically reduced and almost all colonies would become quasi-extinct by 2100. We conclude that the species should be listed as threatened under the ESA.
    Description: We acknowledge support of NASA (80NSSC20K1289) to SJ, MH, and of NSF—OPP (1744794) to SJ, ML.
    Keywords: climate risk assessments ; Endangered Species Act ; foreseeable future ; population projections ; resiliency, redundancy and representation (3Rs) ; sea ice projections ; species distribution ; treatment of scientific uncertainty
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  • 85
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    Unknown
    Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
    Publication Date: 2022-05-27
    Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2022.
    Description: Attenuation from fish can reduce the intensity of acoustic signals and significantly decrease detection range for long-range active and passive sensing in the ocean. This makes it important to understand the relevant mechanisms and accurately predict attenuation from fish in underwater acoustic sensing. Formulations for predicting attenuation from fish, however, depend on the accurate characterization of population density and spatial distribution of fish groups along long-range propagation paths, which is difficult to achieve using conventional survey methods. In previous investigations of attenuation from fish, population densities were inferred from reductions in the intensity of long-range acoustic signals caused by diel or seasonal shoaling patterns of fish groups. Here, Ocean Acoustic Waveguide Remote Sensing (OAWRS) is used to instantaneously image massive Norwegian herring shoals that stretch for thousands of square kilometers and simultaneously measure attenuation from these shoals within the active OAWRS transmissions, as well as attenuation to ship-radiated tonals detected by Passive Ocean Acoustic Waveguide Remote Sensing (POAWRS). Reductions in signal intensity are predicted using a normal-mode-based analytical theory derived from first principles for acoustic propagation and scattering through inhomogeneities in an ocean waveguide. The predictions of the waveguide attenuation formulation are in agreement with measured reductions from attenuation, where the position, size, and population density of the fish groups are characterized using OAWRS imagery as well as in situ echosounder measurements of the specific shoals occluding the propagation path. Common heuristic formulations that employ free space scattering assumptions for attenuation from fish groups are not in agreement with measurements here, and waveguide scattering theory is found to be necessary for accurate predictions. It is experimentally and theoretically shown that attenuation can be significant when the sensing frequency is near the resonance frequency of the shoaling fish, where scattering losses from the fish swimbladders and damping from fish flesh is most significant. Negligible attenuation was observed in previous OAWRS and POAWRS surveys because the frequency of the acoustic signals was sufficiently far from the swimbladder resonance peak of the shoaling fish or the packing densities of the fish shoals were not sufficiently high.
    Description: This work was supported by: • Office of Naval Research under grant number N00014-17-1-2197. • Office of Naval Research via the Graduate Traineeship Award under grant number N00014-18-1-2085.
    Keywords: Attenuation ; Fish ; Acoustic
    Repository Name: Woods Hole Open Access Server
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  • 86
    Publication Date: 2022-08-15
    Description: The sinking of carbon fixed via net primary production (NPP) into the ocean interior is an important part of marine biogeochemical cycles. NPP measurements follow a log-normal probability distribution, meaning NPP variations can be simply described by two parameters despite NPP's complexity. By analyzing a global database of open ocean particle fluxes, we show that this log-normal probability distribution propagates into the variations of near-seafloor fluxes of particulate organic carbon (POC), calcium carbonate, and opal. Deep-sea particle fluxes at subtropical and temperate time-series sites follow the same log-normal probability distribution, strongly suggesting the log-normal description is robust and applies on multiple scales. This log-normality implies that 29% of the highest measurements are responsible for 71% of the total near-seafloor POC flux. We discuss possible causes for the dampening of variability from NPP to deep-sea POC flux, and present an updated relationship predicting POC flux from mineral flux and depth.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , NonPeerReviewed
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  • 87
    Publication Date: 2022-06-22
    Description: Silicic calderas are volcanic systems whose unrest evolution is more unpredictable than other volcano types because they often do not culminate in an eruption. Their complex structure strongly influences the post-collapse volcano-tectonic evolution, usually coupling volcanism and ground deformation. Among such volcanoes, the Campi Flegrei caldera (southern Italy) is one of the most studied. Significant long- and short-term ground deformations characterize this restless volcano. Several studies performed on the marinecontinental succession exposed in the central sector of the Campi Flegrei caldera provided a reconstruction of ground deformation during the last 15 kyr. However, considering that over one-third of the caldera is presently submerged beneath the Pozzuoli Gulf, a comprehensive stratigraphic on-land-offshore framework is still lacking. This study aims at reconstructing the offshore succession through analysis of high-resolution single and multichannel reflection seismic profiles and correlates the resulting seismic stratigraphic framework with the stratigraphy reconstructed on-land. Results provide new clues on the causative relations between the intra-caldera marine and volcaniclastic sedimentation and the alternating phases of marine transgressions and regressions originated by the interplay between ground deformation and sea-level rise. The volcano-tectonic reconstruction, provided in this work, connects the major caldera floor movements to the large Plinian eruptions of Pomici Principali (12 ka) and Agnano Monte Spina (4.55 ka), with the onset of the first post-caldera doming at ~10.5 ka. We emphasize that ground deformation is usually coupled with volcanic activity, which shows a self-similar pattern, regardless of its scale. Thus, characterizing the long-term deformation history becomes of particular interest and relevance for hazard assessment and definition of future unrest scenarios.
    Description: Published
    Description: 855-882
    Description: 1V. Storia eruttiva
    Description: JCR Journal
    Keywords: offshore stratigraphy ; seismic units ; La Starza succession ; volcanism, ; 04.08. Volcanology ; 04.04. Geology ; 04.07. Tectonophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 88
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    Wiley
    In:  EPIC3Journal of Geophysical Research-Oceans, Wiley, 126(12), pp. e2021JC017633, ISSN: 0148-0227
    Publication Date: 2022-06-29
    Description: The transient climate response (TCR) is 20% higher in the Alfred Wegener Institute Climate Model (AWI-CM) compared to the Max Planck Institute Earth System Model (MPI-ESM) whereas the equilibrium climate sensitivity (ECS) is by up to 10% higher in AWI-CM. These results are largely independent of the two considered model resolutions for each model. The two coupled CMIP6 models share the same atmosphere-land component ECHAM6.3 developed at the Max Planck Institute for Meteorology (MPI-M). However, ECHAM6.3 is coupled to two different ocean models, namely the MPIOM sea ice-ocean model developed at MPI-M and the FESOM sea ice-ocean model developed at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI). A reason for the different TCR is related to ocean heat uptake in response to greenhouse gas forcing. Specifically, AWI-CM simulations show stronger surface heating than MPI-ESM simulations while the latter accumulate more heat in the deeper ocean. The vertically integrated ocean heat content is increasing slower in AWI-CM model configurations compared to MPI-ESM model configurations in the high latitudes. Weaker vertical mixing in AWI-CM model configurations compared to MPI-ESM model configurations seems to be key for these differences. The strongest difference in vertical ocean mixing occurs inside the Weddell and Ross Gyres and the northern North Atlantic. Over the North Atlantic, these differences materialize in a lack of a warming hole in AWI-CM model configurations and the presence of a warming hole in MPI-ESM model configurations. All these differences occur largely independent of the considered model resolutions.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , NonPeerReviewed
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  • 89
    Publication Date: 2022-06-22
    Description: Thirteen samples of mortar collected from different masonry structures of the Curia of Pompey the Great and from three mixtilinear basins located within the Sacred Area of Largo Argentina were studied. Despite the use of the same volcanic deposit, known as "Pozzolane Rosse", to produce the fine aggregate in all these mortars, it was possible to highlight some distinctive features through the combination of geochemical analyses on selected trace elements and petrographic analysis under an optical microscope, allowing us to distinguish among the three groups of mortars. These types of mortars reflect a perfect coincidence between the diversity of the volcanic materials used and the different construction phases identified and documented by the analysis of the stratigraphic units: a first construction phase of Pompeian age, a second one of Augustan age and, finally, one of the medieval period. Furthermore, it was possible to ascertain two phases of construction of the basins, the second coeval with the interventions of the Augustan period. Finally, this study increases the knowledge on the methods of exploitation and selection of volcanic materials used to produce mortars in Roman times, identifying additional elements useful to establish their origin and chronology of use.
    Description: Published
    Description: 597-610
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 90
    Publication Date: 2022-07-10
    Description: The bacterial communities of Caulerpa lentillifera were studied during an outbreak of an unknown disease in a sea grape farm from Vietnam. Clear differences between healthy and diseased cases were observed at the order, genus, and Operational Taxonomic Unit (OTU) level. A richer diversity was detected in the diseased thalli of C. lentillifera, as well as the dominance of the orders Flavobacteriales (phylum Bacteroidetes) and Phycisphaerales (Planctomycetes). Aquibacter, Winogradskyella, and other OTUs of the family Flavobacteriaceae were hypothesized as detrimental bacteria, this family comprises some well-known seaweed pathogens. Phycisphaera together with other Planctomycetes and Woeseia were probably saprophytes of C. lentillifera. The Rhodobacteraceae and Rhodovulum dominated the bacterial community composition of healthy C. lentillifera. The likely beneficial role of Bradyrhizobium, Paracoccus, and Brevundimonas strains on nutrient cycling and phytohormone production was discussed. The bleaching of diseased C. lentillifera might not only be associated with pathogens but also with an oxidative response. This study offers pioneering insights on the co-occurrence of C. lentillifera-attached bacteria, potential detrimental or beneficial microbes, and a baseline for understanding the C. lentillifera holobiont. Further applied and basic research is urgently needed on C. lentillifera microbiome, shotgun metagenomic, metatranscriptomic, and metabolomic studies as well as bioactivity assays are recommended.
    Repository Name: EPIC Alfred Wegener Institut
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  • 91
    Publication Date: 2022-06-14
    Description: Industrialization in the Northern Hemisphere has led to warming and pollution of natural ecosystems. We used paleolimnological methods to explore whether recent climate change and/or pollution had affected a very remote lake ecosystem, i.e. one without nearby direct human influence. We compared sediment samples that date from before and after the onset of industrialization in the mid-nineteenth century, from four short cores taken at water depths between 12.1 and 68.3 m in Lake Bolshoe Toko, eastern Siberia. We analyzed diatom assemblage changes, including diversity estimates, in all four cores and geochemical changes (mercury, nitrogen, organic carbon) from one core taken at an intermediate water depth. Chronologies for two cores were established using 210Pb and 137Cs. Sedimentation rates were 0.018 and 0.033 cm year−1 at the shallow- and deep-water sites, respectively. We discovered an increase in light planktonic diatoms (Cyclotella) and a decrease in heavily silicified euplanktonic Aulacoseira through time at deep-water sites, related to more recent warmer air temperatures and shorter periods of lake-ice cover, which led to pronounced thermal stratification. Diatom beta diversity in shallow-water communities changed significantly because of the development of new habitats associated with macrophyte growth. Mercury concentrations increased by a factor of 1.6 since the mid-nineteenth century as a result of atmospheric fallout. Recent increases in the chrysophyte Mallomonas in all cores suggested an acidification trend. We conclude that even remote boreal lakes are susceptible to the effects of climate change and human-induced pollution.
    Repository Name: EPIC Alfred Wegener Institut
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  • 92
    Publication Date: 2022-05-26
    Description: Author Posting. © The Author(s), 2021. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Journal of Phycology, doi:10.1111/jpy.13135.
    Description: Gymnodinium gracile, described from the coasts of Denmark in 1881, is one of the first described unarmored dinoflagellates. Individuals which morphologically fit with the original description were isolated from the English Channel (North‐East Atlantic). The SSU rRNA gene sequences were identical to the sequences identified as Balechina pachydermata and Gymnodinium amphora from the Mediterranean Sea and Brazil. We propose the transfer of Gymnodinium gracile into the genus Balechina as B. gracilis comb. nov. These sequences constitute an independent lineage, clustering with numerous environmental sequences from polar to tropical waters. The widespread distribution, the high plasticity in size, shape and coloration and the difficulties in discerning the fine longitudinal striae have contributed to the description of numerous synonyms: Amphidinium vasculum, Balechina pachydermata (=Gymnodinium pachydermatum), Gymnodinium achromaticum, G. abbreviatum, G. amphora, G. dogielii, G. lohmannii (=G. roseum sensu Lohmann 1908), G. situla and Gyrodinium cuneatum (=G. gracile sensu Pouchet 1885).
    Description: F.G. was supported by the convention #2101893310 between CNRS INSU and the French Ministry of Ecology (MTES) for the implementation of the Monitoring Program of the European Marine Strategy Framework directive (MSFD) for pelagic habitats and the descriptor ‘biodiversity’. Samples were collected during the ECOPEL Manche 2018 spring and summer cruises (CNRS-LOG) onboard R/V "Antea" (IRD, Institut de Recherche pour le Développement) in the frame of the cited convention and the CPER ‘Hauts de France’ project MARCO supported by the French state, the ‘Hauts de France’ French Region and the European Regional Development Founds (ERDF).
    Keywords: Dinophyta ; naked Dinoflagellata ; Gymnodiniales ; new combination ; taxonomy ; molecular phylogenetics
    Repository Name: Woods Hole Open Access Server
    Type: Preprint
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  • 93
    Publication Date: 2022-05-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Howarth, R. W., Chan, F., Swaney, D. P., Marino, R. M., & Hayn, M. Role of external inputs of nutrients to aquatic ecosystems in determining prevalence of nitrogen vs. phosphorus limitation of net primary productivity. Biogeochemistry, (2021), https://doi.org/10.1007/s10533-021-00765-z.
    Description: Whether net primary productivity in an aquatic ecosystem is limited by nitrogen (N), limited by phosphorus (P), or co-limited by N & P is determined by the relative supply of N and P to phytoplankton compared to their elemental requirements for primary production, often characterized by the “Redfield” ratio. The supply of these essential nutrients is affected by both external inputs and biogeochemical processes within the ecosystem. In this paper, we examine external sources of nutrients to aquatic systems and how the balance of N to P inputs influences nutrient limitation. For ocean subtropical gyres, a relatively balanced input of N and P relative to the Redfield ratio from deep ocean sources often leads to near co-limitation by N and P. For lakes, the external nutrient inputs come largely from watershed sources, and we demonstrate that on average the N:P ratio for these inputs across the United States is well above that needed by phytoplankton, which may contribute to P limitation in those lake that experience this average nutrient loading. Watershed inputs are also important for estuaries and coastal marine ecosystems, but ocean sources of nutrients are also significant contributors to overall nutrient loads. The ocean-nutrient sources of N and P are very often at or below the Redfield ratio of 16:1 molar, and can be substantially so, particularly in areas where the continental shelf is wide. This large input of coastal ocean nutrients with a low N:P ratio is one factor that may make N limitation more likely in many coastal marine ecosystems than in lakes.
    Description: Preparation of this manuscript was supported by a National Science Foundation Grant # 1654845 from the Long Term Research in Environmental Biology program, a grant from the Atkinson Center for a Sustainable Future at Cornell University, and by an endowment given to Cornell by David R. Atkinson to support a professorship held by RWH.
    Keywords: Nutrient limitation ; Nitrogen limitation ; Phosphorus limitation ; Aquatic ecosystems ; Estuaries ; Coastal marine ecosystems ; Redfield ratio ; NANI ; NAPI ; Nutrient stoichiometry
    Repository Name: Woods Hole Open Access Server
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  • 94
    Publication Date: 2022-05-27
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Sequeira, A. M. M., O'Toole, M., Keates, T. R., McDonnell, L. H., Braun, C. D., Hoenner, X., Jaine, F. R. A., Jonsen, I. D., Newman, P., Pye, J., Bograd, S. J., Hays, G. C., Hazen, E. L., Holland, M., Tsontos, V. M., Blight, C., Cagnacci, F., Davidson, S. C., Dettki, H., Duarte, C. M., Dunn, D. C., Eguiluz, V. M., Fedak, M., Gleiss, A. C., Hammerschlag, N., Hindell, M. A., Holland, K., Janekovic, I., McKinzie, M. K., Muelbert, M. M. C., Pattiaratchi, C., Rutz, C., Sims, D. W., Simmons, S. E., Townsend, B., Whoriskey, F., Woodward, B., Costa, D. P., Heupel, M. R., McMahon, C. R., Harcourt, R., & Weise, M. A standardisation framework for bio-logging data to advance ecological research and conservation. Methods in Ecology and Evolution, 12, (2021): 996–1007, https://doi.org/10.1111/2041-210X.13593.
    Description: 1. Bio-logging data obtained by tagging animals are key to addressing global conservation challenges. However, the many thousands of existing bio-logging datasets are not easily discoverable, universally comparable, nor readily accessible through existing repositories and across platforms, slowing down ecological research and effective management. A set of universal standards is needed to ensure discoverability, interoperability and effective translation of bio-logging data into research and management recommendations. 2. We propose a standardisation framework adhering to existing data principles (FAIR: Findable, Accessible, Interoperable and Reusable; and TRUST: Transparency, Responsibility, User focus, Sustainability and Technology) and involving the use of simple templates to create a data flow from manufacturers and researchers to compliant repositories, where automated procedures should be in place to prepare data availability into four standardised levels: (a) decoded raw data, (b) curated data, (c) interpolated data and (d) gridded data. Our framework allows for integration of simple tabular arrays (e.g. csv files) and creation of sharable and interoperable network Common Data Form (netCDF) files containing all the needed information for accuracy-of-use, rightful attribution (ensuring data providers keep ownership through the entire process) and data preservation security. 3. We show the standardisation benefits for all stakeholders involved, and illustrate the application of our framework by focusing on marine animals and by providing examples of the workflow across all data levels, including filled templates and code to process data between levels, as well as templates to prepare netCDF files ready for sharing. 4. Adoption of our framework will facilitate collection of Essential Ocean Variables (EOVs) in support of the Global Ocean Observing System (GOOS) and inter-governmental assessments (e.g. the World Ocean Assessment), and will provide a starting point for broader efforts to establish interoperable bio-logging data formats across all fields in animal ecology.
    Description: We are thankful to ONR and UWA OI for funding the workshop, and to ARC for DP210103091. A.M.M.S. was funded by a 2020 Pew Fellowship in Marine Conservation, and also supported by AIMS. C.R. was the recipient of a Radcliffe Fellowship at the Radcliffe Institute for Advanced Study, Harvard University.
    Keywords: bio-logging template ; data accessibility and interoperability ; data standards ; metadata templates ; movement ecology ; sensors ; telemetry ; tracking
    Repository Name: Woods Hole Open Access Server
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  • 95
    Publication Date: 2022-05-27
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Clevenger, S. J., Benitez-Nelson, C. R., Drysdale, J., Pike, S., Puigcorbe, V., & Buesseler, K. O. Review of the analysis of Th-234 in small volume (2-4 L) seawater samples: improvements and recommendations. Journal of Radioanalytical and Nuclear Chemistry, 329(1), (2021): 1–13, https://doi.org/10.1007/s10967-021-07772-2.
    Description: The short-lived radionuclide 234Th is widely used to study particle scavenging and transport from the upper ocean to deeper waters. This manuscript optimizes, reviews and validates the collection, processing and analyses of total 234Th in seawater and suggests areas of further improvements. The standard 234Th protocol method consists of scavenging 234Th from seawater via a MnO2 precipitate, beta counting, and using chemical recoveries determined by adding 230Th. The revised protocol decreases sample volumes to 2 L, shortens wait times between steps, and simplifies the chemical recovery process, expanding the ability to more rapidly and safely apply the 234Th method.
    Description: The authors would like to acknowledge support from the National Aeronautics and Space Administration (NASA) as part of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) program awards 80NSSC17K0555; and the Woods Hole Oceanographic Institution’s Ocean Twilight Zone study for KOB and SJC.
    Keywords: Thorium-234 analysis ; 234Th particle flux ; Biological carbon pump ; Particle scavenging
    Repository Name: Woods Hole Open Access Server
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  • 96
    Publication Date: 2022-05-25
    Description: Ecological stability under environmental change is determined by both interspecific and intraspecific processes. Particularly for planktonic microorganisms, it is challenging to follow intraspecific dynamics over space and time. We propose a new method, microsatellite PoolSeq barcoding (MPB), for tracing allele frequency changes in protist populations. We successfully applied this method to experimental community incubations and field samples of the diatom Thalassiosira hyalina from the Arctic, a rapidly changing ecosystem. Validation of the method found compelling accuracy in comparison with established genotyping approaches within different diversity contexts. In experimental and environmental samples, we show that MPB can detect meaningful patterns of population dynamics, resolving allelic stability and shifts within a key diatom species in response to experimental treatments as well as different bloom phases and years. Through our novel MPB approach, we produced a large dataset of populations at different time‐points and locations with comparably little effort. Results like this can add insights into the roles of selection and plasticity in natural protist populations under stable experimental but also variable field conditions. Especially for organisms where genotype sampling remains challenging, MPB holds great potential to efficiently resolve eco‐evolutionary dynamics and to assess the mechanisms and limits of resilience to environmental stressors.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 97
    Publication Date: 2022-05-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ralston, D. K., Yellen, B., & Woodruff, J. D. Watershed suspended sediment supply and potential impacts of dam removals for an estuary. Estuaries and Coasts, (2021), https://doi.org/10.1007/s12237-020-00873-3.
    Description: Observations and modeling are used to assess potential impacts of sediment releases due to dam removals on the Hudson River estuary. Watershed sediment loads are calculated based on sediment-discharge rating curves for gauges covering 80% of the watershed area. The annual average sediment load to the estuary is 1.2 Mt, of which about 0.6 Mt comes from side tributaries. Sediment yield varies inversely with watershed area, with regional trends that are consistent with substrate erodibility. Geophysical and sedimentological surveys in seven subwatersheds of the Lower Hudson were conducted to estimate the mass and composition of sediment trapped behind dams. Impoundments were classified as (1) active sediment traps, (2) run-of-river sites not actively trapping sediment, and (3) dammed natural lakes and spring-fed ponds. Based on this categorization and impoundment attributes from a dam inventory database, the total mass of impounded sediment in the Lower Hudson watershed is estimated as 4.9 ± 1.9 Mt. This represents about 4 years of annual watershed supply, which is small compared with some individual dam removals and is not practically available given current dam removal rates. More than half of dams impound drainage areas less than 1 km2, and play little role in downstream sediment supply. In modeling of a simulated dam removal, suspended sediment in the estuary increases modestly near the source during discharge events, but otherwise effects on suspended sediment are minimal. Fine-grained sediment deposits broadly along the estuary and coarser sediment deposits near the source, with transport distance inversely related to settling velocity.
    Description: This work was sponsored by the National Estuarine Research Reserve System Science Collaborative, which is funded by the National Oceanic and Atmospheric Administration and managed by the University of Michigan Water Center (NAI4NOS4190145). Additional support for participating graduate and undergraduates was provided by the Northeast Climate and Adaptation Center and the Hudson River Fund. Additional support for DKR was provided by the Hudson River Foundation (Grant No. 003/19A). Data from sediment cores that were collected in association with this manuscript are archived here: https://doi.org/10.7275/dh3v-0x33.
    Keywords: Dam removal ; Suspended sediment ; Watershed sediment yield ; Sediment supply ; Sediment trapping
    Repository Name: Woods Hole Open Access Server
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  • 98
    Publication Date: 2022-01-18
    Description: Gashydrate, auch „brennendes Eis“ genannt, sind faszinierende, eisähnliche Feststoffe, die aus Wasser- und Gasmolekülen aufgebaut sind und weltweit an allen aktiven und passiven Kontinentalhängen und in Permafrostgebieten vorkommen. Doch ihr unauffälliges Erscheinungsbild täuscht: Die Einschlussverbindungen können beachtliche Mengen Methangas enthalten. Daher besteht einerseits die Hoffnung auf einen möglichen neuen Energieträger und andererseits die Sorge um eine nicht zu unterschätzende Quelle an klimaschädlichem Methangas. Gashydrate, hat die neueste Forschung gezeigt, bieten zudem in vielen Bereichen industrieller Anwendung eine durchaus vielversprechende Alternative zu konventionellen Verfahren. Das vorliegende Buch gibt eine Einführung in die physikalisch-chemischen Grundlagen der Hydratbildung und die Strukturen der Gashydratphasen. Basierend auf diesem grundlegenden Verständnis erklärt es die natürlichen Gashydratvorkommen und zeichnet mögliche Methoden des Abbaus und der Gewinnung von Methangas auf. Es beleuchtet Risiken, die von den Gashydratvorkommen in der Natur ausgehen könnten, und führt in die Möglichkeiten der Nutzung dieser Einschlussverbindungen in verschiedenen industriellen Anwendungsbereichen wie z.B. der Aufbereitung von Abwässern oder der Speicherung von Gasen ein. Zielgruppe dieser kompakten Einführung in die verschiedenen Aspekte der Gashydratforschung sind Studierende der Chemie und Geowissenschaften, Ingenieure, Techniker oder auch Wissenschaftler.
    Language: German
    Type: info:eu-repo/semantics/book
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