ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Elsevier  (203,197)
  • Springer  (80,797)
  • Hindawi
  • 2015-2019  (292,909)
  • 2010-2014  (2)
  • 1985-1989
  • 2018  (292,909)
Collection
Language
Years
Year
  • 1
    Publication Date: 2020-10-13
    Description: Mount Etna is the highest relief in Sicily and represents a unique environment because of its long established and almost continuous eruptive activity, that has moulded its landforms and which has produced distinctive landscapes. Over the past 60 ka both destructive and constructive geological processes have produced the principal morphological features of the volcano such as the wide Valle del Bove depression, monogenic scoria cones and extensive lava flow fields. Relationships between Etna, its environment and human activity began in the Neolithic Period within the mountain foot region and have developed over millennia. Even though there has been a rapid rate of resurfacing by lava during historic times, the impact on human activity has been short-lived, recovery has been rapid and society has adjusted to the ever present hazard in distinctive ways.
    Description: Published
    Description: 467-478
    Description: 1V. Storia eruttiva
    Description: N/A or not JCR
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2020-11-18
    Description: The Pomici di Avellino eruption is the Plinian event of Vesuvius with the highest territorial impact. It affected an area densely inhabited by Early Bronze Age human communities and resulted in the long- term abandonment of an extensive zone surrounding the volcano. Traces of human life beneath the eruption products are very common throughout the Campania Region. A systematic review of the available archaeological data, the study of geological and archaeological sequences exposed in excava- tions, and the reconstruction of the volcanic phenomena affecting single sites has yielded an under- standing of local effects and their duration. The archaeological and volcanological analyses have shown that the territory was rapidly abandoned before and during the eruption, with rare post-eruption at- tempts at resettlement of the same sites inhabited previously. The definition of the distribution and stratigraphy of alluvial deposits in many of the studied sequences leads us to hypothesise that the scarce presence of humans during phases 1 and 2 of the Middle Bronze Age in the wide area affected by the eruption was due to diffuse phenomena of remobilisation of the eruption products, generating long- lasting alluvial processes. These were favoured by the deposition of loose fine pyroclastic material on the slopes of the volcano and the Apennines, and by climatic conditions. A significant resettlement of the territory occurred only hundreds of years after the Pomici di Avellino eruption, during phase 3 of the Middle Bronze Age. This study show the role of volcanic and related phenomena from a Plinian event in the settlement dynamics of a complex territory like Campania.
    Description: Published
    Description: 231-244
    Description: 1V. Storia eruttiva
    Description: 5V. Dinamica dei processi eruttivi e post-eruttivi
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: JCR Journal
    Keywords: Plinian eruption Eruption impact ; Volcanoclastic mass flow ; Vesuvius ; Bronze Age ; Eruption impact
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2020-12-21
    Description: During the last few decades, 4D volcano gravimetry has shown great potential for illuminating subsurface processes at active volcanoes (including some that might otherwise remain “hidden”), especially when combined with other methods (e.g., ground deformation, seismicity, and gas emissions). By supplying information on changes in the distribution of bulk mass over time, gravimetry can provide unique information regarding such processes as magma accumulation in void space, gas segregation at shallow depths, and mechanisms driving volcanic uplift and subsidence. Despite its potential, 4D volcano gravimetry is an underexploited method, not widely adopted by volcano researchers or observatories. The cost of instrumentation and the difficulty in using it under harsh environmental conditions is a significant impediment to the exploitation of gravity at many volcanoes. In addition, retrieving useful information from gravity changes in noisy volcanic environments is a major challenge. While these difficulties are not trivial, neither are they insurmountable; indeed, creative efforts in a variety of volcanic settings highlight the value of 4D gravimetry for understanding hazards as well as revealing fundamental insights into how volcanoes work. Building on previous work, we provide a comprehensive review of 4D volcano gravimetry, including discussions of instrumentation, modeling and analysis techniques, and case studies that emphasize what can be learned from, campaign, continuous, and hybrid gravity observations. We are hopeful that this exploration of 4D volcano gravimetry will excite more scientists about the potential of the method, spurring further application, development, and innovation.
    Description: Published
    Description: 146-179
    Description: 4V. Dinamica dei processi pre-eruttivi
    Description: JCR Journal
    Keywords: time-variable microgravimetry ; volcano gravimetry
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2021-03-16
    Description: The Nevado del Ruiz volcano is considered one of the most active volcanoes in Colombia, which can potentially threaten approximately 600,000 inhabitants. The existence of a glacier and several streams channelling in some main rivers, flowing downslope, increases the risk for the population living on the flank of the volcano in case of unrest, because of the generation of lahars and mudflows. Indeed, during the November 1985 subplinian eruption, a lahar generated by the sudden melting of the glacier killed twenty thousand people in the town of Armero. Moreover, the involvement of the local hydrothermal system has produced in the past phreatic and phreatomagmatic activity, as occurred in 1989. Therefore, the physico-chemical conditions of the hydrothermal system as well as its contribution to the shallow thermal groundwater and freshwater in terms of enthalpy and chemicals require a close monitoring. The phase of unrest occurred since 2010 and culminated with an eruption in 2012, after several years of relative stability, stillmaintains amoderate alert, as required by the high seismicity and SO2 degassing. In October 2013, a sampling campaign has been performed on thermal springs and stream water, located at 2600–5000 m of elevation on the slope of Nevado del Ruiz, analyzed for water chemistry and stable isotopes. Some of these waters are typically steam-heated (low pH and high sulfate content) by the vapour probably separating from a zoned hydrothermal system. By applying a model of steam-heating, based on mass and enthalpy balances, we have estimated themass rate of hydrothermal steam discharging in the different springs. The composition of the hottest thermal spring (Botero Londono) is probably representative of a marginal part of the hydrothermal system, having a temperature of 250 °C and low salinity (Cl ~1500 mg/l), which suggest, along with the retrieved isotope composition, a chiefly meteoric origin. The vapour discharged at the steam vent “Nereidas” (3600 m asl) is hypothesized to be separated from a high temperature hydrothermal system. Based on its composition and on literature data on fluid inclusions, we have retrieved the P-T-X conditions of the deep hydrothermal system, aswell as its pH and fO2. The vapour feeding Nereidas would separate from a biphasic hydrothermal system characterized by the following parameters: t= 315 °C, P= 15 MPa, NaCl = 10 wt%, CO2=5 wt%, and similar proportion between liquid and vapour. Considering also the equilibria involving S-bearing gases and HCl, pH would approach the value of 1.5 while fO2 would correspond to the FeO-Fe2O3 buffer. Chlorine content is estimated at 10,300mg/l. Changes in the magmatic input into the hydrothermal system couldmodify its degree of vapourization and/or P-T-X conditions, thus inducing corresponding variations in vapour discharges and thermal waters. These findings, paralleled by contemporary measurements of water flow rates, could give significant clues on risk evaluation.
    Description: Published
    Description: 40-53
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: JCR Journal
    Keywords: Nevado del Ruiz ; Water isotopes ; Geothermal system ; Equilibrium modelling ; Water chemistry ; 04.08. Volcanology ; 03.02. Hydrology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2021-03-02
    Description: Since hydrofracking is used for shale gas production, human caused seismicity have become a subject of increasing interest. Seismic monitoring is common for earthquakes generated by human operations like mining, reservoir impoundments, hydrocarbon and geothermal production, as well as reinjection of fluids. In Italy the Mw6.1 Reggio-Emilia earthquake of 20 May 2012 triggered particular interest in anthropogenic seismicity. It also raised the question of whether hydrocarbon exploitation induced variations in crustal stress that influenced the generation of these earthquakes. The Italian government commissioned a technical report compiling cases of documented and hypothesized anthropogenic seismicity. Following a governmental request, a technical report was compiled, describing the relation between anthropogenic activities and induced or triggered seismicity in Italy. This paper reviews these cases, on the basis of previously published works, and additional new analyses. Three cases of seismicity in Central Italy, occurring close to anthropogenic activities, are: (i) extraction of carbon dioxide (CO_2) from a borehole near Pieve Santo Stefano, (ii) the impoundment of the Montedoglio reservoir and (iii) geothermal energy production at Mt. Amiata. Since the sites are situated in the seismically active area of the Northern Apennines, we illustrate both by standard seismological analysis as well as by modeling to tackle the challenge of discriminating anthropogenic from natural seismicity.
    Description: Published
    Description: 80-94
    Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Description: JCR Journal
    Keywords: triggered/induced seismicity ; Italy ; CO2 extraction ; reservoir impoundment ; Mt. Amiata ; Upper Tiber Valley ; Solid Earth, Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2020-10-13
    Description: Volcanoes hold a fascination for human beings and, before they were recorded by literate observers, eruptions were portrayed in art, were recalled in legend and became incorporated into religious practices: being viewed as agents of punishment, bounty or intimidation depending upon their state of activity and the culture involved. In the Middle East the earliest record dates from the third millennium BCE and knowledge of volcanoes increased progressively over time. In the first century CE written records noted nine volcanoes in the Mediterranean region plus Mount Cameroon in West Africa, yet by 1380 AD the record only totalled 48, with volcanoes in Japan, Indonesia and Iceland being added. After this the list of continued to increase, but important regions such as New Zealand and Hawaii were only added during the last 200 years. Only from 1900 did the rate of growth decline significantly, but it is sobering to recall that in the twentieth century major eruptions have occurred from volcanoes that were considered inactive or extinct, examples including: Mount Lamington—Papua New Guinea, 1951; Mount Arenal—Costa Rica, 1968 and Nyos—Cameroon, 1986. Although there were instances where the human impact of historical eruptions were studied in detail, with examples including the 1883 eruption of Krakatau and 1943–1952 eruption of Parícutin, these were exceptions and before 1980 there was a significant knowledge gap about both the short and long-term effects of major eruptions on societies. Following a global review, this chapter provides a discussion of the ways in which information has been collected, compiled and disseminated from the earliest times until the 1980s in two case study areas: the Azores Islands (Portugal) and southern Italy. In Italy information on eruptions stretches back to prehistoric times and has become progressively better known over more than 2,000 years, yet even here there remain significant gaps in the record even for events that took place between 1900 and 1990. In contrast, located in the middle of the Atlantic, the Azores have been isolated for much of their history and illustrate the difficulties involved in using indigenous sources to compile, not only assessments of impact, but also at a more basic level a complete list of historical events with accurate dates.
    Description: Published
    Description: 1-25
    Description: 1V. Storia eruttiva
    Description: N/A or not JCR
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2021-03-19
    Description: Syneruptive gas flux time series can, in principle, be retrieved from satellite maps of SO2 collected during and immediately after volcanic eruptions, and used to gain insights into the volcanic processes which drive the volcanic activity. Determination of the age and height of volcanic plumes are key prerequisites for such calculations. However, these parameters are challenging to constrain using satellite-based techniques. Here, we use imagery from OMI and GOME-2 satellite sensors and a novel numerical procedure based on back-trajectory analysis to calculate plume height as a function of position at the satellite measurement time together with plume injection height and time at a volcanic vent location. We applied this new procedure to three Etna eruptions (12 August 2011, 18 March 2012 and 12 April 2013) and compared our results with independent satellite and ground-based estimations. We also compare our injection height time-series with measurements of volcanic tremor, which reflects the eruption intensity, showing a good match between these two datasets. Our results are a milestone in progressing towards reliable determination of gas flux data from satellite-derived SO2 maps during volcanic eruptions, which would be of great value for operational management of explosive eruptions.
    Description: 1) European Research Council under the European Union's Seventh Framework Programme (FP/2.007-2013)/ERC Grant Agreement no. 279802, project 283 CO2Volc. 2) MEDiterranean SUpersite Volcanoes 280 (MED-SUV) WP 3.3.3
    Description: Published
    Description: 79-91
    Description: 5V. Dinamica dei processi eruttivi e post-eruttivi
    Description: JCR Journal
    Keywords: Volcanic SO2 ; Trajectory modelling ; Remote sensing ; Volcanic tremor ; 04.08. Volcanology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2021-06-30
    Description: Volcanic activity exhibits a wide range of eruption styles, from relatively slow effusive eruptions that produce lava flows and lava domes, to explosive eruptions that can inject large volumes of fragmented magma and volcanic gases high into the atmosphere. Although controls on eruption style and scale are not fully understood, previous research suggests that the dynamics of magma ascent in the shallow subsurface (〈 10 km depth) may in part control the transition from effusive to explosive eruption and variations in eruption style and scale. Here we investigate the initial stages of explosive eruptions using a 1D transient model for magma ascent through a conduit based on the theory of the thermodynamically compatible systems. The model is novel in that it implements finite rates of volatile exsolution and velocity and pressure relaxation between the phases. We validate the model against a simple two-phase Riemann problem, the Air-Water Shock Tube problem, which contains strong shock and rarefaction waves. We then use the model to explore the role of the aforementioned finite rates in controlling eruption style and duration, within the context of two types of eruptions at the Soufrière Hills Volcano, Montserrat: Vulcanian and sub-Plinian eruptions. Exsolution, pressure, and velocity relaxation rates all appear to exert important controls on eruption duration. More significantly, however, a single finite exsolution rate characteristic of the Soufrière Hills magma composition is able to produce both end-member eruption durations observed in nature. The duration therefore appears to be largely controlled by the timescales available for exsolution, which depend on dynamic processes such as ascent rate and fragmentation wave speed.
    Description: Published
    Description: 110-139
    Description: 5V. Dinamica dei processi eruttivi e post-eruttivi
    Description: JCR Journal
    Keywords: Magma ascent ; Conduit dynamics ; Soufrière Hills Volcano ; Finite-rate exsolution ; Pressure relaxation ; Velocity relaxation ; 04.08. Volcanology ; Numerical modeling
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2019-01-25
    Description: A combined approach merging stable isotopes and fatty acids was applied to study anthropogenic pollution in the Río Negro estuary. Fatty acid markers of vegetal detritus indicated considerable allochthonous inputs at freshwater sites. Correlative evidence of diatom fatty acids, δ13C, chlorophyll and particulate organic matter suggested the importance of diatoms for the autochthonous organic matter production at the river mouth. Low δ15N values (~0�) and high fatty acid 18:1(n-7) concentrations in the suspended particulate matter, in combination with the peaks of coliforms and ammonium, indicated a strong impact of untreated sewage discharge. The 15N depletion was related to oxygen-limited ammonification processes and incorporation of 15N depleted ammonium to microorganisms. This work demonstrates that the combined use of lipid and isotopic markers can greatly increase our understanding of biogeochemical factors and pollutants influencing estuaries, and our findings highlight the urgent need for water management actions to reduce eutrophication.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2018-04-03
    Description: Harde (2017) proposes an alternative accounting scheme for the modern carbon cycle and concludes that only 4.3% of today's atmospheric CO2 is a result of anthropogenic emissions. As we will show, this alternative scheme is too simple, is based on invalid assumptions, and does not address many of the key processes involved in the global carbon cycle that are important on the timescale of interest. Harde (2017) therefore reaches an incorrect conclusion about the role of anthropogenic CO2 emissions. Harde (2017) tries to explain changes in atmospheric CO2 concentration with a single equation, while the most simple model of the carbon cycle must at minimum contain equations of at least two reservoirs (the atmosphere and the surface ocean), which are solved simultaneously. A single equation is fundamentally at odds with basic theory and observations. In the following we will (i) clarify the difference between CO2 atmospheric residence time and adjustment time, (ii) present recently published information about anthropogenic carbon, (iii) present details about the processes that are missing in Harde (2017), (iv) briefly discuss shortcoming in Harde's generalization to paleo timescales, (v) and comment on deficiencies in some of the literature cited in Harde (2017).
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Publication Date: 2019-02-14
    Description: Mineral ballasting enhances carbon export from the surface to the deep ocean; however, little is known about the role of this process in the ice-covered Arctic Ocean. Here, we propose gypsum ballasting as a new mechanism that likely facilitated enhanced vertical carbon export from an under-ice phytoplankton bloom dominated by the haptophyte Phaeocystis. In the spring 2015 abundant gypsum crystals embedded in Phaeocystis aggregates were collected throughout the water column and on the sea floor at a depth below 2 km. Model predictions supported by isotopic signatures indicate that 2.7 g m−2 gypsum crystals were formed in sea ice at temperatures below −6.5°C and released into the water column during sea ice melting. Our finding indicates that sea ice derived (cryogenic) gypsum is stable enough to survive export to the deep ocean and serves as an effective ballast mineral. Our findings also suggest a potentially important and previously unknown role of Phaeocystis in deep carbon export due to cryogenic gypsum ballasting. The rapidly changing Arctic sea ice regime might favour this gypsum gravity chute with potential consequences for carbon export and food partitioning between pelagic and benthic ecosystems.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2018-06-14
    Description: Sea-ice ecosystems are among the most extensive of Earth’s habitats; yet its autotrophic and heterotrophic activities remain poorly constrained. We employed the in situ aquatic eddy-covariance (AEC) O2 flux method and laboratory incubation techniques (H14CO3−, [3H] thymidine and [3H] leucine) to assess productivity in Arctic sea-ice using different methods, in conditions ranging from land-fast ice during winter, to pack ice within the central Arctic Ocean during summer. Laboratory tracer measurements resolved rates of bacterial C demand of 0.003–0.166 mmol C m−2 day−1 and primary productivity rates of 0.008–0.125 mmol C m−2 day−1 for the different ice floes. Pack ice in the central Arctic Ocean was overall net autotrophic (0.002–0.063 mmol C m−2 day−1), whereas winter land-fast ice was net heterotrophic (− 0.155 mmol C m−2 day−1). AEC measurements resolved an uptake of O2 by the bottom-ice environment, from ~ − 2 mmol O2 m−2 day−1 under winter land-fast ice to~ − 6 mmol O2 m−2 day−1 under summer pack ice. Flux of O2-deplete meltwater and changes in water flow velocity masked potential biological-mediated activity. AEC estimates of primary productivity were only possible at one study location. Here, productivity rates of 1.3 ± 0.9 mmol O2 m−2 day−1, much larger than concurrent laboratory tracer estimates (0.03 mmol C m−2 day−1), indicate that ice algal production and its importance within the marine Arctic could be underestimated using traditional approaches. Given careful flux interpretation and with further development, the AEC technique represents a promising new tool for assessing oxygen dynamics and sea-ice productivity in ice-covered regions.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2018-10-01
    Description: In paleoenvironmental studies, the mineralogical composition of sediments is an important indicator. In combination with other indicators, they contribute to the understanding of changes in sediment sourcing as well as in weathering and depositional processes. Fourier transforminfrared spectroscopy (FTIRS) spectra contain information on mineralogical composition because eachmineral has a unique absorption pattern in the mid-IR range. Although easily obtained, FTIR spectra are often too complex to infermineral concentrations directly. In this study, we use a calibration set of ca. 200 sediment samples conventionally measured using X-ray diffraction (XRD) in order to developmultivariate, partial least squares (PLS) regressionmodels relatingmineral contents to sediment spectra. Good correlations were obtained for the most common minerals (e.g. quartz, K-feldspar, illite, plagioclase, smectite, calcite). Correlation coefficients ranged from 0.85 to 0.92, coefficients for the validation varied from 0.64 to 0.80, the number of latent variables (PLS regression components) in the models ranged between 3 and 7 and the range of variation of the RMSEcv gradient was from 15.28 to 5.7.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2018-11-12
    Description: The study investigates the in-situ strength of sediments across a plate boundary décollement using drilling parameters recorded when a 1180-m-deep borehole was established during International Ocean Discovery Program (IODP)Expedition 370, Temperature-Limit of the Deep Biosphere off Muroto (T-Limit). Information of the in-situ strength of the shallow portion in/around a plate boundary fault zone is critical for understanding the development of accretionary prisms and of the décollement itself. Studies using seismic reflection surveys and scientific ocean drillings have recently revealed the existence of high pore pressure zones around frontal accretionary prisms, which may reduce the effective strength of the sediments. A direct measurement of in-situ strength by experiments, however, has not been executed due to the difficulty in estimating in-situ stress conditions. In this study, we derived a depth profile for the in-situ strength of a frontal accretionary prism across a décollement from drilling parameters using the recently established equivalent strength (EST) method. At site C0023, the toe of the accretionary prism area off Cape Muroto, Japan, the EST gradually increases with depth but undergoes a sudden change at ~ 800 mbsf, corresponding to the top of the subducting sediment. At this depth, directly below the décollement zone, the EST decreases from ~ 10 to 2 MPa, with a change in the baseline. This mechanically weak zone in the subducting sediments extends over 250 m (~ 800–1050 mbsf), corresponding to the zone where the fluid influx was discovered, and high-fluid pressure was suggested by previous seismic imaging observations. Although the origin of the fluids or absolute values of the strength remain unclear, our investigations support previous studies suggesting that elevated pore pressure beneath the décollement weakens the subducting sediments.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2020-03-29
    Description: Most palaeo-deep-water reconstructions are based on geochemical information stored in the calcareous shells of Cibicidoides species but hardly anything is known about their life cycle, population dynamics or ecology. The number of specimens of a single Cibicidoides species can locally be very limited and species may be lacking completely during certain intervals in the geological past. As a consequence, geochemical analyses are often carried out on lumped Cibicidoides spp. assuming that they share the same epizoic to epifaunal habitat and precipitated their shell in comparable offsets to surrounding bottom water mass properties. However, there is a growing body of evidence that particularly Cibicidoides pachyderma and its morphotypes C. mundulus and C. kullenbergi, may not be reliable bottom water recorders. We have recently developed aquaria that allowed, for the first time, observations of Cibicidoides pachyderma var. C. mundulus under in situ pressure and temperature. Experiments were carried out with and without artificial sediments to simulate soft sediments and rocks, respectively. Seawater was set to pH 8 and pH 7.4 to simulate more or less particulate carbon export or more or less ventilation of bottom water. Our experiments demonstrate that C. mundulus may opt for an epifaunal or an infaunal habitat depending on elapsed time following physical disturbance, pH, current activity, the availability of sediments and growth. The specimen's initial response following transfer from atmospheric pressure into the high-pressure aquaria was to immerse into the sediment or to cover more or less parts of the test with aggregated sediments or algae. However, within 24 h a strong rheotaxis became apparent and most specimens moved to sites of increased current activity under normal pH conditions (pH 8). Only few specimens remained in algae cysts or in the sediment in the pH-8 experiment. On the contrary, all specimens under pH 7.4 agglutinated a firm sediment cyst around their test and remained infaunal throughout the experimental period of three months. Independent of pH, growth was only observed in specimens that lived within an agglutinated cyst or infaunal. A solid thick cyst covered the specimens of the pH 7.4 experiment throughout the experiment and possibly restricted water exchange between the in-cyst water and the surrounding artificial bottom water mass. We suggest that a more fragile and possibly more porous sedimentary envelope may, at least temporally, have covered the infaunal specimens under pH 8 but no evidence for this was found upon termination of the experiment.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Cham, Springer, 259 p., ISBN: 978-3-319-93284-2
    Publication Date: 2020-06-12
    Description: This open access book presents the proceedings volume of the YOUMARES 8 conference, which took place in Kiel, Germany, in September 2017, supported by the German Association for Marine Sciences (DGM). The YOUMARES conference series is entirely bottom-up organized by and for YOUng MARine RESearchers. Qualified early career scientists moderated the scientific sessions during the conference and provided literature reviews on aspects of their research field. These reviews and the presenters’ conference abstracts are compiled here. Thus, this book discusses highly topical fields of marine research and aims to act as a source of knowledge and inspiration for further reading and research.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Book , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    facet.materialart.
    Unknown
    Elsevier
    In:  EPIC3Ecological MOdelling, Elsevier, 387, pp. 17-26
    Publication Date: 2020-01-21
    Description: Salpa thompsoni is an important grazer in the Southern Ocean. It is found from the Subtropical Convergence southward to the coastal Antarctic Seas but being most abundant in the Antarctic Polar Frontal Zone. Low temperatures appear to negatively affect their development, limiting their ability to occur in the krill dominated high Antarctic ecosystems. Yet reports indicate that with ocean warming S. thompsoni have experienced a southward shift in their distribution. As they are efficient filter feeders, this shift can result in large-scale changes in the Southern Ocean ecosystem by increasing competitive or predatory interactions with Antarctic krill. To explore salp bloom dynamics in the Southern Ocean a size-structured S. thompsoni population model was developed with growth, consumption, reproduction and mortality rates dependent on temperature and chlorophyll a conditions. The largest uncertainties in S. thompsoni population ecology are individual and population growth rates, with a recent study identifying the possibility that the life cycle could be much shorter than previously considered. Here we run a suite of hypothesis scenarios under various environmental conditions to determine the most appropriate growth rate. Temperature and chlorophyll a were sufficient drivers to recreate seasonal and interannual dynamics of salp populations at two locations. The most suitable growth model suggests that mean S. thompsoni growth rates are likely to be ∼1mm body length d−1, 2-fold higher than previous calculations. S. thompsoni biomass was dependent on bud release time, with larger biomass years corresponding to bud release occurring during favorable environmental conditions; increasing the survival and growth of blastozooids and resulting in higher embryo release. This model confirms that it is necessary for growth and reproductive rates to be flexible in order for the salp population to adapt to varying environmental conditions and provides a framework that can examine how future salp populations might respond to climate change.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    facet.materialart.
    Unknown
    Elsevier
    In:  EPIC3Encyclopedia of the Anthropocene, Encyclopedia of the Anthropocene, Elsevier, 3, pp. 217-228
    Publication Date: 2020-02-09
    Description: Human influence on the climate system, through greenhouse gas emissions, is clear and climate warming unequivocal. Recent climate change has had widespread impacts on natural systems including shifts in the ranges (distributions) of land, freshwater, and marine organisms. Effects of these biogeographical shifts transcend single-species to impact on ecosystem goods and services resulting in significant social and economic costs to human communities. In this article we provide a general overview of these factors by reviewing current evidence from terrestrial, freshwater, and marine ecosystems.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Handbook on Marine Environment Protection, Handbook on Marine Environment Protection, Berlin, Springer, 1024 p., pp. 463-485, ISBN: 978-3-319-60154-0
    Publication Date: 2018-07-23
    Description: Underwater sound is ubiquitous throughout the world’s oceans. Evaluating its impact and relevance for the marine fauna is highly complex and hampered by a paucity of data, lack of understanding and ambiguity of terms. When comparing sound (an energetic pollutant) with substantial pollutants (chemical, biological or marine litter) two notable differences emerge: Firstly, while sound propagates instantaneously away from the source, it also ceases immediately within minutes of shutting off the source. Anthropogenic noise is hence per-se ephemeral, lending itself to a set of in-situ mitigation strategies unsuitable for mitigation of persistent pollutants. Secondly, while pollution with hazardous substances can readily be described quantitatively with few parameters (environmental concentration as the most important one), the description of sound and its impact on aquatic life is of much higher complexity, as to be evidenced by the issues multifaceted description following hereinafter.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Publication Date: 2019-04-11
    Description: This study forms part II of two papers describing ECHAM6-FESOM, a newly established global climate model with a unique multi-resolution sea ice-ocean component. While part I deals with the model description and the mean climate state, here we examine the internal climate variability of the model under constant present-day (1990) conditions. We (1) assess the internal variations in the model in terms of objective variability performance indices, (2) analyze variations in global mean surface temperature and put them in context to variations in the observed record, with particular emphasis on the recent warming slowdown, (3) analyze and validate the most common atmospheric and oceanic variability patterns, (4) diagnose the potential predictability of various climate indices, and (5) put the multi-resolution approach to the test by comparing two setups that differ only in oceanic resolution in the equatorial belt, where one ocean mesh keeps the coarse ~1° resolution applied in the adjacent open-ocean regions and the other mesh is gradually refined to ~0.25°. Objective variability performance indices show that, in the considered setups, ECHAM6-FESOM performs overall favourably compared to five well-established climate models. Internal variations of the global mean surface temperature in the model are consistent with observed fluctuations and suggest that the recent warming slowdown can be explained as a once-in-one-hundred-years event caused by internal climate variability; periods of strong cooling in the model (‘hiatus’ analogs) are mainly associated with ENSO-related variability and to a lesser degree also to PDO shifts, with the AMO playing a minor role. Common atmospheric and oceanic variability patterns are simulated largely consistent with their real counterparts. Typical deficits also found in other models at similar resolutions remain, in particular too weak non-seasonal variability of SSTs over large parts of the ocean and episodic periods of almost absent deep-water formation in the Labrador Sea, resulting in overestimated North Atlantic SST variability. Concerning the influence of locally (isotropically) increased resolution, the ENSO pattern and index statistics improve significantly with higher resolution around the equator, illustrating the potential of the novel unstructured-mesh method for global climate modeling.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Boundary Layer Meteorol., Springer, 166, pp. 301-325
    Publication Date: 2019-02-15
    Description: In climate and weather prediction models the near-surface turbulent fluxes of heat and momentum and related transfer coefficients are usually parametrized on the basis of Monin–Obukhov similarity theory (MOST). To avoid iteration, required for the numerical solution of the MOST equations, many models apply parametrizations of the transfer coefficients based on an approach relating these coefficients to the bulk Richardson number Rib.However, the parametrizations that are presently used in most climate models are valid only for weaker stability and larger surface roughnesses than those documented during the Surface Heat Budget of the Arctic Ocean campaign (SHEBA). The latter delivered a well-accepted set of turbulence data in the stable surface layer over polar sea-ice. Using stability functions based on the SHEBA data, we solve the MOST equations applying a new semi-analytic approach that results in transfer coefficients as a function of Rib and roughness lengths for momentum and heat. It is shown that the new coefficients reproduce the coefficients obtained by the numerical iterative method with a good accuracy in the most relevant range of stability and roughness lengths. For small Rib , the new bulk transfer coefficients are similar to the traditional coefficients, but for large Ri b they are much smaller than currently used coefficients. Finally, a possible adjustment of the latter and the implementation of the new proposed parametrizations in models are discussed.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Global Ecology and Oceanography of Harmful Algal Blooms, Global Ecology and Oceanography of Harmful Algal Blooms, Springer, 16 p., pp. 187-203, ISBN: 978-3-319-7006
    Publication Date: 2018-06-23
    Description: Coastal systems partially surrounded by land such as coastal embayments, estuaries and fjords have characteristics that affect the development of harmful algal blooms. Among these, shallow water depths and geophysical constraints from surrounding land masses favour stronger links between the water column and bottom sediments. Typical circulation patterns (e.g., in estuaries) can limit the exchange with offshore waters and favour cell retention. Sub-mesoscale and high-frequency processes are particularly important physical factors that influence pattern and persistence of HABs in coastal systems. Coupling with benthic nutrient fluxes or seed banks from the bottom is enhanced as the degree of physical robustness of coastal systems decreases. The links between bottom cyst distribution patterns and intensity or extension of HABs are still not fully understood. The importance of intra-specific diversity has been highlighted for many HAB species but tools are needed to assist in situ identification of these various life cycle stages. Alternative metabolic strategies, such as mixotrophy or reliance on organic nutrients and allelochemically mediated species interactions, can play a critical role in the development of HA blooms particularly in semi-confined coastal environments. Future work should address the influence of climate change and of coastal aquaculture on blooms of these harmful species in coastal environments.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2019-10-04
    Description: An integrative inventory of the amphipod scavenging fauna (Lysianassoidea), combining morphological identifications with DNA barcoding, is provided here for the Filchner area situated in the south-eastern Weddell Sea. Over 4400 lysianassoids were investigated for species richness and relative abundances, covering 20 different stations and using different sampling devices, including the southernmost baited traps deployed so far (76°S). High species richness was observed: 29 morphospecies of which 5 were new to science. Molecular species delimitation methods were carried out with 109 cytochrome c oxidase I gene (COI) sequences obtained during this study as well as sequences from specimens sampled in other Antarctic regions. These distance-based analyses (trees and the Automatic Barcode Gap Discovery method) indicated the presence of 42 lineages; for 4 species, several (cryptic) lineages were found. More than 96% of the lysianassoids collected with baited traps belonged to the species Orchomenella pinguides s. l. The diversity of the amphipod scavenger guild in this ice-bound ecosystem of the Weddell Sea is discussed in the light of bottom–up selective forces. In this southernmost part of the Weddell Sea, harbouring spawning and nursery grounds for silverfish and icefishes, abundant fish and mammalian food falls are likely to represent the major food for scavengers. Finally, the importance of biodiversity surveys in the context of the establishment of a marine protected area in this region (Weddell Sea MPA) is highlighted and how future studies can contribute to a better understanding the ecological role of scavengers in this system is discussed.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2018-02-26
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Publication Date: 2018-06-05
    Description: Fossil carbonate skeletons of marine organisms are archives for understanding the development and evolution of palaeo-environments. However, the correct assessment of past environment dynamics is only possible when pristine skeletons and their biogenic characteristics are unequivocally distinguishable from diagenetically-alteredskeletal elements and non-biogenic features. In this study, we extend our work on diagenesis of biogenic aragonite (Casella et al. 2017) to the investigation of biogenic low-Mg calcite using brachiopod shells. We examined and compared microstructural characteristics inducedby laboratory-based alteration to structural features derived from diagenetic alteration in natural environments. We used four screening methods: cathodoluminescence (CL), cryogenic and conventional field emission-scanning electronmicroscopy (FE-SEM), atomic force microscopy (AFM) and electron backscatter diffraction (EBSD).We base our assessments of diagenetic alteration and overprint on measurements of, a) images of optical overprint signals, b) changes in calcite crystal orientation patterns, and c) crystal co-orientation statistics. According to the screening process, altered and overprinted samples define two groups. In Group 1 the entire shell is diagenetically overprinted, whereas in Group 2 the shell contains pristine as well as overprinted parts. In the case of Group 2 shells, alteration occurred either along the periphery of the shell including the primary layer or at the interior-facing surface of the fibrous/columnar layer. In addition, we observed an important mode of the overprinting process, namely the migration of diagenetic fluids through the endopunctae corroborated by mineral formation and overprinting in their immediate vicinity, while leaving shell parts between endopunctae in pristine condition. Luminescence (CL) and microstructural imaging (FE-SEM) screening give first-order observations of the degree of overprint as they cover macro-to micron scale alteration features. For a comprehensive assessment of diagenetic overprint these screening methods should be complemented by screening techniques such as EBSD and AFM. They visualise diagenetic changes at submicron and nanoscale levels depicting the replacement of pristine nanocomposite mesocrystal biocarbonate (NMB) by inorganic rhombohedral calcite (IRC). The integration of screening methods allows for the unequivocal identification of highly-detailed alteration features as well as an assessment of the degree of diagenetic alteration.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Handbook on Marine Environment Protection, Cham, Switzerland, Springer, 21 p., pp. 353-373, ISBN: 978-3-319-60156-4
    Publication Date: 2018-02-09
    Description: In this chapter, the effects of temperature change—as a main aspect of climate change—on marine biodiversity are assessed. Starting from a general discussion of species responses to temperature, the chapter presents how species respond to warming. These responses comprise adaptation and phenotypic plasticity as well as range shifts. The observed range shifts show more rapid shifts at the poleward range edge than at the equator-near edge, which probably reflects more rapid immigration than extinction in a warming world. A third avenue of changing biodiversity is change in species interactions, which can be altered by temporal and spatial shifts in interacting species. We then compare the potential changes in biodiversity to actual trends recently addressed in empirical synthesis work on local marine biodiversity, which lead to conceptual issues in quantifying the degree of biodiversity change. Finally we assess how climate change impacts the protection of marine environments.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2018-12-05
    Description: We study the basement configuration in the slow-spreading Eurasia Basin, Arctic Ocean. Two multichannel seismic (MCS) profiles, which we acquired during ice-free conditions with a 3600 m long streamer, image the transition from the North Barents Sea Margin into the southern Eurasia Basin. The seismic lines resolve the up to 5000 m thick sedimentary section, as well as the crustal architecture of the southern Eurasia Basin along 120 km and 170 km, respectively. The seismic data show large faulted and rotated basement blocks. Gravity modeling indicates a thin basement with a thickness of 1–3 km and a density of 2.8*103 kg/m3 between the base of the sediments and the top of the mantle, which indicates exhumed and serpentinized mantle. The Gakkel spreading ridge, located in northern prolongation of the seismic lines is characterized by an amagmatic or sparsely magmatic segment. From the structural similarity between the basement close to the ultra-slow spreading ridge and our study area, we conclude that the basement in the Eurasia Basin is predominantly formed by exhumed and serpentinized mantle, with magmatic additions. An initial strike-slip movement of the Lomonosov Ridge along the North Barents Sea Margin and subsequent near-orthogonal opening of the Nansen Basin is supposed to have brought mantle material to the surface, which was serpentinized during this process. Continuous spreading thinned the serpentinized mantle and subsequent normal faulting produced distinct basement blocks. We propose that mantle exhumation has likely been active since the opening of the Eurasia Basin.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Building Bridges at the Science-Stakeholder Interface, Building Bridges at the Science-Stakeholder Interface, Springer, 133 p., pp. 73-78, ISBN: 978-3-319-75919-7
    Publication Date: 2019-08-15
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev , info:eu-repo/semantics/other
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2019-04-17
    Description: In fall 1995, during a survey in Abrolhos coral reef system (southwestern Atlantic, Brazil), significant densities (143–6174 cells L-1) of small thecate dinoflagellates were detected. Analysis of this material in scanning and transmission electron microscopy confirmed the presence of four taxa assigned to the potentially toxic genus Azadinium: A. dexteroporum Percopo et Zingone, A. luciferelloides Tillmann et Akselman, A. cf. polongum Tillmann and Azadinium sp. The latter taxon showed external morphological features quite distinct from any Azadinium taxon yet described, but its formal description as a new species depends on more detailed analysis. Species of Azadinium have never been confirmed in Brazilian waters until now, although the toxins produced by these dinoflagellates, the azaspiracids, have been detected in Brazilian southern coast without recognition of their producing organisms. The highest densities of Azadinium spp. occurred at stations south of and over the Abrolhos Bank, which receive higher nutrient concentrations due to upwelling of deep and nutrient-rich water masses.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    facet.materialart.
    Unknown
    Elsevier
    In:  EPIC3Deep Sea Research Part II: Topical Studies in Oceanography, Elsevier, 149, pp. 25-30, ISSN: 09670645
    Publication Date: 2018-06-19
    Description: The deep basins of the Bransfield Strait (BS) are ventilated by Weddell Sea (WS) waters from different origins. Depending on the source and density, these water masses follow different routes across the complex topography near the tip of the Antarctic Peninsula and thus into the Bransfield Strait abyss. Using a global setup of the Finite Element Sea-ice Ocean Model (FESOM) we show that the WS waters found at the western WS continental shelf break have a higher influence on the short period variability of BS bottom waters than the waters present over the continental shelf. Adding passive tracers to the glacial melt water (GMW) from two different origins, Larsen Ice Shelf (LIS) and Filchner-Ronne Ice Shelf (FRIS), we show that the GMW from FRIS has a larger influence on BS bottom waters than the GMW from LIS. FRIS GMW has a higher concentration in the BS eastern basin, while LIS GMW is more abundant in the BS central basin. This duality mainly leads to the difference between BS central and eastern basins seen on the observations. This is a novel result and we believe is a significant contribution to the understanding of the BS-WS circulation and interactions.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2018-06-27
    Description: This study focusses on the last glacial–deglacial–Holocene spatial and temporal variability in sea-ice cover based on organic geochemical analyses of marine sediment cores from the subarctic Pacific and the Bering Sea. By means of the sea-ice proxy “IP25” and phytoplankton-derived biomarkers (specific sterols and alkenones), we reconstruct the spring sea-ice conditions, (summer) sea-surface temperature (SST) and primary productivity, respectively. The large variability of sea ice was explained by a combination of local and global factors, such as solar insolation, global climate anomalies and sea-level changes controlling the oceanographic circulation and water mass exchange between the subarctic Pacific and the Bering Sea. During the Last Glacial Maximum, extensive sea-ice cover prevailed over large part of the subarctic Pacific and the Bering Sea. The following deglaciation is characterized by a rapid sea-ice advance and retreat. During cold periods (Heinrich Stadial 1 and Younger Dryas) seasonal sea-ice cover generally coincided with low alkenone SSTs and low primary productivity. Conversely, during warmer intervals (Bølling/Allerød, Early Holocene) reduced sea-ice or ice-free conditions prevailed in the study area. At the northern Bering Sea continental shelf a late-Early/Mid Holocene shift to marginal sea-ice conditions is in line with the simultaneous wide-spread sea-ice recovery observed in the other Arctic marginal seas and is likely initiated by the lower Northern Hemisphere insolation and surface-water cooling.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Publication Date: 2018-09-04
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2018-09-28
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Publication Date: 2021-04-25
    Keywords: 551 ; VKB 350 ; 38.20
    Language: English
    Type: anthologyArticle , publishedVersion
    Format: 186-209
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    facet.materialart.
    Unknown
    Springer | Berlin [u.a.]
    Publication Date: 2021-04-25
    Description: Colonial non-zooxanthellate corals from deep-water coral reefs, Lophelia pertusa and Madrepora oculata, produce large amounts of extracellular mucus (EMS). This mucus has various functions, e.g., an antifouling capability protecting the coral skeleton from attacks of endolithic and boring organisms. Both corals show thick epithecal and exothecal skeletal parts with a clear lamellar growth pattern. The formation of the epitheca is unclear. It is supposed that the EMS play a central role during the calcification process of the epithecal skeletal parts. Staining with the fluorochrome tetracycline has shown an enrichment of Ca2+ ions in the mucus. In order to investigate this hypothesis, the protein content of the mucus and the intracrystalline organic matter from newly formed epithecal aragonite of Madrepora oculata was determined via sodium dodecyl sulfate (SDS) gel electrophoresis. Identical band patterns within both substances could be detected, one around 45 kDa molecular weight and a cluster around 30-35 kDa molecular weight. The occurrence of identical protein patterns within the mucus and in the newly formed aragonite confirms the idea that the mucus plays an important role during the organomineralization of the coral epitheca.
    Keywords: 551 ; VU 000 ; 38.20
    Language: English
    Type: anthologyArticle , publishedVersion
    Format: 731-744
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Publication Date: 2021-03-29
    Description: The incorporation of hydrogen in enstatite in a hydrous system containing various amounts of NaCl was investigated at 25 kbar. The hydrogen content in enstatite shows a clear negative correlation to the NaCl-concentration in the system. The most favourable explanation is the reduction of water fugacity due to dilution. Other reasons for the limited hydrogen incorporation at high NaCl levels, such as a significant influence of Na+ on the defect chemistry or an exchange between OH- and Cl-in enstatite, appear much less important. A partition coefficient D Na En/Fluid = 0.0013 could be determined, demonstrating that Na is less incompatible in enstatite than H. The new results support the idea that dissolved components have to be considered when the total hydrogen storage capacity in nominally anhydrous minerals is estimated, especially in geological settings with high levels of halogens, such as subduction zones.
    Keywords: KEnstatite; Hydrogen incorporation;Water activity; Sodium; Chlorine ; 551
    Language: English
    Type: article , publishedVersion
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Publication Date: 2021-03-29
    Description: The coprecipitation of U (VI) with iron corrosion products from aqueous solutions by zero valent iron was investigated. The evidence of coprecipitation was demonstrated by conducting experiments with well characterized scrap iron,pyrite and a mixture of both materials with experimental durations of up to four months. Results indicate that under anoxic conditions only less than one tenth of the immobilized U(VI) was associated with the surface of scrap iron, whereas theremaining amount is entrapped in aging corrosion products.
    Keywords: 551
    Language: English
    Type: anthologyArticle , acceptedVersion
    Format: 577-586
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Publication Date: 2018-03-08
    Description: This contribution proposes a cautious way of constructing the susceptibility classes obtained from favourability modeling of landslide occurrences. It is based on the ranks of the numerical values obtained by the modelling. Such ranks can be displayed in the form of histograms, cumulative curves, and prediction patterns resembling maps. A number of models have been proposed and in this contribution the following will be compared in terms of their respective rankings for equal area classes: fuzzy set function, empirical likelihood ratio, linear and logistic regression, and Bayesian prediction function. The analyses performed and contrasted exemplify a generalized methodology for comparing predictions that should allow evaluating prediction patterns from any model. Unfortunately, many applications in the scientific literature use methods of characterizing prediction quality that make comparison hard or impossible. A database from a study area in the Mountain Community of Tirano in Valtellina, Lombardy Region, northern Italy, is used to illustrate how the results of the different models and strategies of analysis show the relevance of the properties of the database over those of the models.
    Description: Published
    Description: 1135-1144
    Description: 2TR. Ricostruzione e modellazione della struttura crostale
    Keywords: Landslide susceptibility, spatial support, spatial relationships, prediction models, prediction patterns, target pattern, ranked classes, cross-validation, database signature ; 04.04. Geology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2018-03-08
    Description: Which are the trends that are transforming research management and how do research organizations respond to these changes? What are the available services to support research during EC projects’ life-cycles? Are there research information systems in use and to which extent are they integrated? The paper is structured as follows: a survey conducted over a sample of universities and research centers in Italy is presented in section 2. Section 3 describes significant case studies. Section 4 illustrates mobility figures and trends in EU funded projects. Section 5 concludes with considerations about trends and suggestions for improvement.
    Description: Published
    Description: 309-314
    Description: 7TM. Sviluppo e Trasferimento Tecnologico
    Description: N/A or not JCR
    Keywords: Research support services ; CRIS ; research information management ; Human Resources Strategy for Researchers
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Publication Date: 2018-04-06
    Description: The EOS-1 Terra ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) has acquired about 200 images (100 of them sufficiently cloud-free to be used) over Mt. Etna since 1999. This chapter shows the results from the analysis of 10 years Mt Etna activity using thermal infrared (TIR) high spatial resolution data by a semi-automatic procedure that extracts radiance values of the summit area with the goal of detecting variation related to eruptive events. Night time data showed a good correlation with the main eruptive events that occurred both in the summit and in the flank areas. A comparison of the variance of maximum ASTER TIR radiance with variance of the maximum AVHRR TIR radiance (Advanced Very High Resolution Radiometer) for the same area confirms good correlation in terms of trend and values between the two data sets. Finally this study emphasizes the importance of high spatial resolution TIR data during background monitoring to detect changes in the thermal emission that may be related to an impending eruption and the need to further improve the spatial resolution in the TIR channels to better separate the thermal active areas in volcanic systems.
    Description: Published
    Description: 409-428
    Description: 5V. Dinamica dei processi eruttivi e post-eruttivi
    Description: 2SR. VULCANI - Servizi e ricerca per la Società
    Description: 5IT. Osservatori
    Keywords: Remote sensing observation, volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2018-03-26
    Description: At Vulcano (Aeolian Islands, Italy), different measurement methods have been developed for more than 30 years and models were formulated to account for the real time evolution of the actual solphataric activity. The results of a long term monitoring of surface temperature and of CO2 flux from soil, reviewed in a multidisciplinary framework, are presented here. These two parameters, monitored at the ground surface, highlighted local variations of the hydrothermal release and the time series of data showed in several instances, different range of values. The background and anomalous ranges defined by this long term monitoring are robust by a statistical point of view. The long term data-series offered a useful tool to verify conceptual framework and to better define the natural hazard evaluation integrating “classical” and “new” investigation techniques. Moreover, La Fossa area lays in a geodynamic context with active seismo- tectonic processes, frequently perturbing the pressure field of the hydrothermal system under investigation. Any perturbation in the pressure state variable (P) of the system, results in an excited state of its components and a relevant transfer of energy and mass towards the surface starts to counterbalance the perturbation. The continuous monitoring of surface temperature reveals the effects of the forces guiding the heat flows whereas the space variation of temperature indicates the rising paths of hydrothermal and magmatic fluids. The occurrence of new fumaroles and mofetes, or even changing emission rates of fluids by these vents, rises questions about the evolution of the equilibrium state of buried hydrothermal system, or about changing physical condition of overburden rocks. The conceptual framework suggesting the potential of our time series of field data is that a rock body, can be seen as a multiphase geochemical system where the fluid phases play a crucial role in defining the physical changes of the body and its response to the different forces acting on it. The changes of pore pressure depend on the balance between gas phases production and gas leaked out from a geochemical system. Analyses of fluxes at the system boundaries can give information on the equilibrium of the interacting geospheres. Even if playing variables are too many, some specific compounds and parameters can be selected as indicators of the state of the system.#
    Description: Published
    Description: Yokohama, Japan
    Description: 4V. Dinamica dei processi pre-eruttivi
    Keywords: Long term monitoring ; Vulcano ; Fluid geochemistry
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: Conference paper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-02-16
    Description: No abstract
    Description: Published
    Description: 6A. Geochimica per l'ambiente
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2018-02-19
    Description: No abstract
    Description: Published
    Description: 6A. Geochimica per l'ambiente
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2018-03-16
    Description: In this paper, we analyze the tropospheric delay observed on some ground-based CGPS stations in a dense small regional network and its time evolution during extreme weather conditions. In particular, we studied two severe weather events occurring in the Campanian Region (Italy) on October 12, 2012 and December 2, 2014, reaching 42 and 28 mm rainfall during about 1 h at Naples (MAFE) and Gragnano (GRAG) stations respectively. The main concern of this study is the retrieval of the precipitable water (PW) from co-located GPS and meteorological stations. We investigate the correlation between PW and rain amount at ground level. We analyse phase residuals for each visible GPS satellite using sky plots of the phase residuals along the GPS satellites tracks, showing that the two phenomena are shown in the phase residual plots. Moreover, we compare PWdata retrieved from observed meteorological data and from models (GPT2 and ECMWF), evidencing that there is a need for co-located CGPS and weather stations to improve the assessment of water content in the troposphere.
    Description: Published
    Description: 293-302
    Description: 4A. Oceanografia e clima
    Description: 7A. Geofisica per il monitoraggio ambientale e geologia medica
    Keywords: Precipitable water ; Tropospheric delay ; GPT2 ; ECMWF ; GPS ; 01.01. Atmosphere
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Publication Date: 2018-03-02
    Description: The action of using someone else’s production, ideas, or research without acknowledging the source and then claiming credit for them is known as plagiarism. Plagiarism is in principle a moral offense; it is not always an illegal action but certainly is an ethical complex case. Copying without permission or stealing someone else’s work violates the standard codes of scholarly conduct and ethical behavior in professional scientific research. Science may be somewhat more prone to plagiarism in that scholars exchange ideas and proposals more frequently than artists, for example. Workshops, scientific meetings, and round tables are places where primitive and preliminary researches are presented and discussed before their official presentation. This chapter discusses plagiarism and self plagiarism and tries to point out the role of the scientific community toward this kind of scientific misconduct.
    Description: Published
    Description: 5TM. Informazione ed editoria
    Keywords: Copyright infringement, Ethical conduct, Plagiarism. ; 05.03. Educational, History of Science, Public Issues
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Publication Date: 2018-02-16
    Description: Among the considerable number of studies that can be carried out using muons, we pay specific attention to the radiography of volcanoes based on the same principle of the X-ray radiography of human body. Thanks to their high penetration capability, cosmic-ray muons can be used to reconstruct the density distribution of the interior of huge structures by measuring the attenuation induced by the material on the muon flux. In particular, the quantitative understanding of the inner structure of volcanoes is a key-point to forecast the dangerous stages of activity and mitigate volcanic hazards. The instrumental approach is currently based on the detection of muons crossing hodoscopes made up of scintillator planes. Unfortunately, these detectors are affected by a strong background comprised by accidental coincidence of vertical shower particles, horizontal high-energy electrons and upward going particles. We propose an alternative technique based on the detection of the Cherenkov light produced by muons. This can be achieved with an imaging atmospheric Cherenkov telescope composed of a high reflectivity optical system that focus the Cherenkov light onto a multi-pixel focal camera with fast read-out electronics. The Cherenkov light emitted by a muon is imaged on the camera as an annular pattern which contains information to reconstruct the direction of the incident muon. We have estimated that using the Cherenkov imaging technique for muon radiography of volcanoes gives the advantage of a negligible background and improved spatial resolution, compared to the majority of the particle detectors. We present results of simulations based on a telescope with a positioning resolution of 13.5 m which corresponds to an acceptance of 9 cm2 sr. The telescope is located 1500 m far from a toy-model volcano, namely, a cone with a base diameter of 500 m and a height of 240 m. We test the feasibility of the proposed method by estimating the minimum number of observation nights needed to resolve inner empty conduits of different diameter.
    Description: Published
    Description: 122–125
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: N/A or not JCR
    Keywords: Imaging Atmospheric Cherenkov Telescope ; Volcano radiography ; Muons, ; Volcano monitoring ; Mount Etna
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2018-03-19
    Description: The importance of historical earthquake data is largely recognized by both seismologists and engineers, who use such data in a wide range of applications. At the European-Mediterranean scale, several databases dealing with historical earthquake data – mostly intensity data points – exist and are constantly maintained and updated, as well as national earthquake catalogues. In addition, a number of studies on historical earthquakes are published every year. Most of these activities are being performed at a national scale, depending on each country’s needs, and according to diverse methodologies. As a result, the earthquake history of Europe is today fragmented in a puzzle of different, only partially overlapping sets of data, which, at the continent scale, are not homogeneously collected and interpreted. This situation is particularly evident in the frontier areas, where historical earthquakes are often interpreted in a conflicting and/or partial way by the catalogues of the bordering countries. In addition, the background information upon which several historical catalogues are built is not published or not easily accessible. In recent years, a major effort was made to bridge over these gaps, by establishing cooperation among existing national databases, and creating new ones according to common standards. Particular attention was devoted to retrieve the earthquake background information, that is, the results of historical earthquake investigation in terms of a paper, a report, a book chapter, a map, etc. As most of the information on an historical earthquake can be summarized in a set of Macroseismic Data Points (MDPs) – i.e. a list of localities (name and coordinates) with a macroseismic intensity assessment and the related macroseismic scale – a dedicated effort was addressed to make such data publicly available. The described activities resulted in the European Archive of Historical Earthquake Data (AHEAD). The Archive is conceived as a pan-European common and open platform supporting the research activities in the field of historical seismology by (i) tracing back, preserving and granting access to the sources of data on the earthquake history of Europe (papers, reports, MDPs, and catalogues), and (ii) establishing relations among these data. AHEAD inventories multiple sets of information concerning each European earthquake in the time-window 1000–1899. The AHEAD web portal (http://www.emidius.eu/AHEAD/) gives access, as of today, to 4,722 earthquakes and the related background information as provided by 338 data sources. All these data can be queried by earthquake and by study, through a user-friendly web-interface. The distinguishing feature of AHEAD is to grant access not only to one study, but to all the available (published) data sources dealing with each individual earthquake, allowing researchers to take into account the different point of views and interpretations.
    Description: Published
    Description: 359-369
    Description: 3T. Storia Sismica
    Description: 4T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Description: 4IT. Banche dati
    Keywords: historical seismology ; seismicity ; historical earthquakes ; 04.06. Seismology ; 05.02. Data dissemination
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Publication Date: 2018-03-26
    Description: We present soil temperature data from a peripheral fumarole emission of Mt Etna at the top end of a radial fracture called Bottoniera. This area lies in the northern flank of the volcano (2,500m a.s.l.), and was interested by fissure eruption during 2002/2003. In the steam heated soil lying around the fumarole release, a shallow vertical profile has been monitored from October 2009 to September 2012. We estimated the local surface heat flux and compared its time variations to the eruptive activity occurred during the monitoring period. The eruptive vents were located on the opposite flank, (〉3200m a.s.l.), far about 4km. The heat flux from this peripheral emission has been highly influenced by the eruptive activity. Its time variations are correlated to the variable rates of products emitted from January 2011 to April 2012. Different ranges of heat flux values have been associated to the pre-eruptive phase, to the productive eruption period and to the end of this eruptive cycle. The decrease of heat flux was registered before the end of the eruptive cycle. The continuous thermal monitoring revealed in real time that ascending magma through the active conduits is the heating bottom source of the heat flux dispersed by a complex network of active fractures present in this area. The recorded data suggest the steam heated soil around fumaroles vents as a possible new investigation field for a low cost monitoring of the local variation in the structural weakness of the apparatus. Extending this thermal monitoring to the other steaming grounds of this complex volcanic system we could also follow variations of the fluid circulation paths and obtain direct information about local pore pressure changes. A multivariate analysis of recorded data could suggest, which part of this complex apparatus is being involved, time by time, with the ongoing evolution. It would contribute to the evaluation of flank instability caused by physical changes occurring on the network of active fractures, and inferred by multidisciplinary investigations (such as deformation patterns, tectonic lineaments and geochemical features of underground waters and diffuse gas emissions).
    Description: Published
    Description: Yokohama, Japan
    Description: 4V. Dinamica dei processi pre-eruttivi
    Description: 5V. Dinamica dei processi eruttivi e post-eruttivi
    Keywords: Fumaroles ; Steam heated Soil ; Thermal monitoring ; Eruptive cycle ; Fluid geochemistry
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: Conference paper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Publication Date: 2019-03-26
    Description: The shallow vertical temperature profile has been measured in the proximity of an eruptive fissure far about 4 km north-northeast from Mt. Etna central craters. The monitoring site was a steam-heated soil lying between a group of flank fractures on the upper northeast flank of Mt. Etna (Italy), i.e., on the northeast rift. We chose this area because it was close to an eruptive fissure, that opened in 2002 and extended from about 2500 to about 1500 m a.s.l., with our aim being to determine a connection between this fracture system and the ongoing volcanic activity. Heat flux anomalies from the ground from September 2009 to September 2012 were evaluated. Changes in the hydrothermal release—which can be related to variations in volcanic activity—are discussed and compared to the published geophysical data. The heat flux ranges varied during the pre-eruptive (from about 7 to 38 W×m−2), syn-eruptive (from about 3 to 49W×m−2), and post-eruptive phases, with the heat released being lowest at the latter phase (from about 1 to 20 W×m−2). Moreover, the heat flux time variation was strongly correlated with the eruption rate from the new southeast crater between January 2011 and April 2012. The migration of magma through active conduits acts as a changing heating source for steam-heated soils located above the active fractures. Our findings suggest that tracking the heat flux above active fractures constitutes a useful investigation field for low-cost thermal monitoring of volcanic activity. Time variations in their emissions could highlight the relationship between a hydrothermal circuit and the local network of fractures, possibly indicating variation in the structural weakness of a volcanic edifice. Continuous monitoring of heat flux, combined with a realistic model, would contribute to multidisciplinary investigations aimed at evaluating changes in volcano dynamics.
    Description: National Department of Civil Protection
    Description: Published
    Description: 31
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: JCR Journal
    Keywords: Volcanic activity ; Ground temperature ; Heat flux ; Continuous monitoring ; 04.08. Volcanology ; 05.04. Instrumentation and techniques of general interest
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Publication Date: 2019-03-26
    Description: The examples of geochemical monitoring results provided in this review article show the close relationships among data analysis, interpretation, and modeling. We particularly focus on describing the fieldwork procedures, since any theoretical approach must always be verified and supported by field data, rather than just by experiments controlled in laboratory.
    Description: Fluids discharged from volcanic systems are the direct surface manifestation of magma degassing at depth and provide primary insights for evaluating the state of volcanic activity. We review the geochemical best practice in volcanic surveillance based to a huge amount of monitoring data collected at different active volcanoes using both continuous and discontinuous approaches. The targeted volcanoes belong to the Aeolian Arc located in the Tyrrhenian Sea (Italy), and they have exhibited different activity states during the monitoring activities reported here. La Fossa cone on Vulcano Island has been in an uninterrupted quiescent stage characterized by variable solfataric activity. In contrast, Stromboli Island has shown a persistent mild explosive activity, episodically interrupted by effusive eruptions (in 1985, 2002, 2007, and 2014). Panarea Island, which is the summit of a seamount rising from the seafloor of the southern Tyrrhenian Sea, showed only undersea fluid release. The only observable clues of active volcanism at Panarea Island have been impulsive changes in the undersea fluid release, with the last submarine gas burst event being observed in November 2002. The geochemical monitoring and observations at each of these volcanoes has directly involved the volcanic plume and/or the fumarole vents, thermal waters, and diffuse soil degassing, depending on the type of manifestations and the level of activity encountered. Through direct access to the magmatic samples (when possible) and the collection of as much observable data related to the fluid release as possible, the aim has been (i) to verify the thermodynamic equilibrium condition, (ii) to discern among the possible hydrothermal, magmatic, marine, and meteoric sources in the fluid mixtures, (iii) to develop models of the fluid circulation supported by data, (iv) to follow the evolution of these natural systems by long-term monitoring, and (v) to support surveillance actions related to defining the volcanic risk and the evaluation and possible mitigation of related hazards. The examples provided in this review article show the close relationships among data analysis, interpretation, and modeling. We particularly focus on describing the fieldwork procedures, since any theoretical approach must always be verified and supported by field data, rather than just by experiments controlled in laboratory. Indeed the natural systems involve many variables producing effects that cannot be neglected. The monitored volcanic systems have been regarded as natural laboratories, and all of the activities have focused on both volcanological research and surveillance purposes in order to ensure that these two goals have overlapped. An appendix is also included that explains the scientific approach to the systematic activities, regarding geochemical monitoring of volcanic activity.
    Description: Published
    Description: 241-276
    Description: 4V. Processi pre-eruttivi
    Description: JCR Journal
    Keywords: geochemical methodologies ; Vulcano ; Stromboli ; Panarea ; Geochemical Monitoring
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Publication Date: 2021-03-29
    Description: Five volcanic tuffs ranging from dacitic tuffs of Hungary to rhyolite, phonolite and basaltic tuffs of Germany were consolidated under laboratory conditions. Prior to consolidation an anti-hygro, a hydrous consolidant, which reduces the swelling ability of clay minerals, was applied. The three consolidants, a silicic acid ester (SAE), an elastic silicic acid ester (eSAE) and an acrylate resin (PMMA) were applied on test specimens under vacuum. Petrographic characterisation (polarizing microscopy, XRD, SEM) provided data for fabric analyses and the mineral composition of the tuffs. Changes in fabric, effective porosity, density, tensile strength, ultrasonic wave velocity were evaluated after the treatment. Weathering simulation tests such as hygric dilatation and thermal dilatation aimed to prove the effectiveness of consolidation and the durability of consolidated tuff samples. More than 500 samples were analysed. The tests showed that SAE caused the highest increase in indirect tensile strength. The water absorption and the pore size distribution of the tuffs were modified by consolidation. The PMMA reduced the water absorption the most, whereas SAE modified it the least. All the tested consolidants increased the thermal dilatation of the tuffs. The changes in hygric dilatation were not uniform: for most tuffs SAE increased and PMMA decreased the hygric dilatation, although the clay-rich Habichtswald tuff showed the opposite trend. The changes in hygric and thermal behaviour of consolidated tuff require special care when specific consolidants are chosen. These products modify the physical properties of consolidated tuffs and change the behaviour of weathering.
    Keywords: Strengthening agents; Tuff; Silicic acid ester; PMMA; Durability ; 551
    Language: English
    Type: article , publishedVersion
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2021-03-29
    Keywords: Albrecht-von-Haller-Institut für Pflanzenwissenschaften / Abteilung für Palynologie und Klimadynamik ; Palaeolimnology; Holocene climate; Diatoms; Green algae; Pollen; Karst ; 551
    Language: English
    Type: article , publishedVersion
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2021-03-29
    Description: A 782 d solubilization study using not shaken batch experiments and involving one uranium-bearing rock and three natural carbonate minerals was conducted to characterize uranium (U) leaching under oxic conditions. Results showed that aqueous U concentration increased continuously with a solubilization rate of 0.16 mgm-2h-1 for the first 564 d (1.5 y). After 1.5 y, U concentration reached a maximum value (saturation) and decreased afterwards. The saturation concentration of 54 mgL-1 (mean value) was influenced to various extent by the presence of carbonate minerals. Dissolution/precipitation, adsorption or ion exchange processes appear to control U solubilization.
    Keywords: 551
    Language: English
    Type: anthologyArticle , acceptedVersion
    Format: 425-435
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Publication Date: 2021-04-25
    Keywords: 551 ; VU 000 ; 38.20
    Language: English
    Type: anthologyArticle , publishedVersion
    Format: 179-211
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Publication Date: 2021-04-25
    Keywords: 551 ; VU 000 ; 38.20
    Language: English
    Type: anthologyArticle , publishedVersion
    Format: 102-120
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Publication Date: 2021-04-25
    Keywords: 551 ; VU 000 ; 38.20
    Language: English
    Type: anthologyArticle , publishedVersion
    Format: 121-133
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2021-03-29
    Description: The veneer cladding of the Oeconomicum (OEC, Göttingen), the State Theatre of Darmstadt (STD, Darmstadt) and of the State and University Library (SUB, Göttingen) is characterised by pronounced bowing after a short time of exposure. Direct comparison of bowing data related to measurements from 2000 to 2003 at the SUB clearly show that the amplitude in bowing had significantly increased. The bowing is different in intensity and orientation (concave, convex). The cladding material (Peccia marble, Rosa Estremoz marble and Carrara marble) are different in lattice preferred orientation, grain size distribution and grain interlocking. Depending on the bowing, panels may show cracks mostly initiated at the dowels. The percentage of visible cracks and breakouts increases with the amplitude of bowing except for the STD. Repetitive heatingcooling under dry conditions leads to considerable inelastic residual strain only after the first or second thermal cycle. The residual strain continuously increases again if water is present, whereby the moisture content after a thermal cycle has a certain impact on the decay rate. The water-enhanced thermal dilatation strongly correlates with the deterioration rate obtained from the laboratory bow test. Detailed petrophysical investigations provide evidence that with increasing bowing a decrease of mechanical properties (flexural strength or breaking load at dowel hole) occur. Marble degradation is also connected with the increase in porosity and a general shift of the maximum pore radii to larger pore sizes...
    Keywords: Bowing; Marble; Building mapping;Residual strain;Thermal expansion; Bowing potential ; 551
    Language: English
    Type: article , publishedVersion
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Ocean Dynamics, Springer, pp. 1-17
    Publication Date: 2019-01-23
    Description: Mesoscale eddies in the open ocean are mostly formed by baroclinic instability, in which the available potential energy from the large-scale slope of the isopycnals is converted into the kinetic energy of the flow around the eddy. As a permissible form of motion within a rapidly rotating and stratified fluid eddies driven by baroclinic instability are important for the poleward and vertical transport, not only of physical properties, but also biogeochemical ones. In this paper, we present observations from four cyclonic eddies in the Antarctic Circumpolar Current. We have sorted them by apparent age, based on altimeter data and consideration of the degree of homogenisation of the potential temperature-salinity(θS) relationship, and then looked at the spatial distribution of measures of fine-scale variability in the upper thermocline. The youngest eddy shows isopycnals which are domed upwards and it contains a variety of waters with differing temperature-salinity characteristics. The fine-scale variability is higher in the core of the eddy. The older eddies show a core which is more homogeneous in potential temperature and salinity. The isopycnals are flatter in the centre of the eddy, and in cross-section, they can be M-shaped, so that the steepest gradients are concentrated around the edge. The fine-scale variability is more concentrated around the edges where the density gradients are stronger. We hypothesise that lateral stirring and mixing processes within the eddy homogenise the water so that the temperature-salinity relationship becomes tighter. When the eddy eventually collapses, this modified water can be released back into the flow. Thus, we see how the interplay of mesoscale and small-scale processes are modifying water mass properties and, potentially, regulate biogeochemical processes.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3YOUMARES 8 - Ocean across boundaries: Learning from each other, Kiel, Germany, 2017-09-13-2017-09-15Cham, Springer
    Publication Date: 2019-09-13
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2022-05-25
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Regional Studies in Marine Science 18 (2018): 1-10, doi:10.1016/j.rsma.2017.12.004.
    Description: The variations of temperature and salinity in the Sudanese coastal zone of the Red Sea are studied for the first time using measurements acquired from survey cruises during 2009–2013 and from a mooring during 2014–2015. The measurements show that temperature and salinity variability above the permanent pycnocline is dominated by seasonal signals, similar in character to seasonal temperature and salinity oscillations observed further north on the eastern side of the Red Sea. Using estimates of heat flux, circulation and horizontal temperature/salinity gradients derived from a number of sources, we determined that the observed seasonal signals of temperature and salinity are not the product of local heat and mass flux alone, but are also due to alongshore advection of waters with spatially varying temperature and salinity. As the temperature and salinity gradients, characterized by warmer and less saline water to the south, exhibit little seasonal variation, the seasonal salinity and temperature variations are closely linked to an observed seasonal oscillation in the along-shore flow, which also has a mean northward component. We find that the inclusion of the advection terms in the heat and mass balance has two principal effects on the computed temperature and salinity series. One is that the steady influx of warmer and less saline water from the south counteracts the long-term trend of declining temperatures and rising salinities computed with only the local surface flux terms, and produces a long-term steady state in temperature and salinity. The second effect is produced by the seasonal alongshore velocity oscillation and most profoundly affects the computed salinity, which shows no seasonal signal without the inclusion of the advective term. In both the observations and computed results, the seasonal salinity signal lags that of temperature by roughly 3 months.
    Description: The SPS surveys were funded by the Norwegian Norad’s Program for Master Studies and organized by IMR–RSU in Port Sudan. The central Red Sea mooring data were acquired as part of a WHOI–KAUST collaboration funded by Award Nos. USA00001, USA00002, and KSA00011 to the WHOI by the KAUST in the Kingdom of Saudi Arabia. The work of I. Skjelvan and A.M. Omar was partly supported by the Research Council of Norway through the MIMT Center for Research-based Innovation. This work is part of a Ph.D. project at GFI–UiB funded by the Norwegian Quota program .
    Keywords: Coastal Red Sea ; Temperature ; Salinity ; Time series ; Seasonality ; Alongshore advection
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Quaternary Science Reviews 185 (2018): 135-152, doi:10.1016/j.quascirev.2018.02.012.
    Description: The largest coherent cold-water coral (CWC) mound province in the Atlantic Ocean exists along the Mauritanian margin, where up to 100 m high mounds extend over a distance of ∼400 km, arranged in two slope-parallel chains in 400–550 m water depth. Additionally, CWCs are present in the numerous submarine canyons with isolated coral mounds being developed on some canyon flanks. Seventy-seven Uranium-series coral ages were assessed to elucidate the timing of CWC colonisation and coral mound development along the Mauritanian margin for the last ∼120,000 years. Our results show that CWCs were present on the mounds during the Last Interglacial, though in low numbers corresponding to coral mound aggradation rates of 16 cm kyr−1. Most prolific periods for CWC growth are identified for the last glacial and deglaciation, resulting in enhanced mound aggradation (〉1000 cm kyr−1), before mound formation stagnated along the entire margin with the onset of the Holocene. Until today, the Mauritanian mounds are in a dormant state with only scarce CWC growth. In the canyons, live CWCs are abundant since the Late Holocene at least. Thus, the canyons may serve as a refuge to CWCs potentially enabling the observed modest re-colonisation pulse on the mounds along the open slope. The timing and rate of the pre-Holocene coral mound aggradation, and the cessation of mound formation varied between the individual mounds, which was likely the consequence of vertical/lateral changes in water mass structure that placed the mounds near or out of oxygen-depleted waters, respectively.
    Description: This study received funding from and contributes to the DFG-projects "Palaeo-WACOM" (HE 3412/17-1) and "Cold-water coral mound development in a tropical upwelling cell – the great wall of(f) Mauritania" (Ti 706/3-1). A. Freiwald received funding from the Hessian initiative for the development of scientific and economic excellence (LOEWE) at the Biodiversity and Climate Research Centre (BiK-F), Frankfurt, Germany.
    Keywords: Lophelia pertusa ; Coral mound ; Submarine canyon ; Uranium-series dating ; Mound aggradation rate ; Last glacial ; Dissolved oxygen concentration ; South Atlantic Central Water ; Mauritanian margin
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Population Ecology 60 (2018): 21-36, doi:10.1007/s10144-018-0615-8.
    Description: Models of sexually-reproducing populations that consider only a single sex cannot capture the effects of sex-specific demographic differences and mate availability. We present a new framework for two-sex demographic models that implements and extends the birth-matrix mating-rule approach of Pollak. The model is a continuous-time matrix model that explicitly includes the processes of mating (which is nonlinear but homogeneous), offspring production, and demographic transitions and survival. The resulting nonlinear model converges to exponential growth with an equilibrium population composition. The model can incorporate age- or stage-structured life histories and flexible mating functions. As an example, we apply the model to analyze the effects of mating strategies (polygamy or monogamy, and mated unions composed of males and females, of variable duration) on the response to sex-biased harvesting. The combination of demographic complexity with the interaction of the sexes can have major population dynamic effects and can change the outcome of evolution on sex-related characters.
    Description: This work was supported by a National Science Foundation Graduate Research Fellowship to ES, under Grant 1122374. HC acknowledges support from NSF Grants DEB1145017 and DEB1257545 and support from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013), ERC Advanced Grant 322989. ES acknowledges support from the Academic Programs office of the Woods Hole Oceanographic Institution.
    Keywords: Birth matrix-mating rule ; BMMR ; Demography ; Matrix population models ; Sex-biased harvest ; Two-sex models
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Progress in Earth and Planetary Science 5 (2018): 19, doi:10.1186/s40645-018-0167-8.
    Description: The Quaternary hemipelagic sediments of the Japan Sea are characterized by centimeter- to decimeter-scale alternation of dark and light clay to silty clay, which are bio-siliceous and/or bio-calcareous to a various degree. Each of the dark and light layers are considered as deposited synchronously throughout the deeper (〉 500 m) part of the sea. However, attempts for correlation and age estimation of individual layers are limited to the upper few tens of meters. In addition, the exact timing of the depositional onset of these dark and light layers and its synchronicity throughout the deeper part of the sea have not been explored previously, although the onset timing was roughly estimated as ~ 1.5 Ma based on the result of Ocean Drilling Program legs 127/128. Consequently, it is not certain exactly when their deposition started, whether deposition of dark and light layers was synchronous and whether they are correlatable also in the earlier part of their depositional history. The Quaternary hemipelagic sediments of the Japan Sea were drilled at seven sites during Integrated Ocean Drilling Program Expedition 346 in 2013. Alternation of dark and light layers was recovered at six sites whose water depths are 〉 ~ 900 m, and continuous composite columns were constructed at each site. Here, we report our effort to correlate individual dark layers and estimate their ages based on a newly constructed age model at Site U1424 using the best available paleomagnetic datum and marker tephras. The age model is further tuned to LR04 δ18O curve using gamma ray attenuation density (GRA) since it reflects diatom contents that are higher during interglacial high-stands. The constructed age model for Site U1424 is projected to other sites using correlation of dark layers to form a high-resolution and high-precision paleo-observatory network that allows to reconstruct changes in material fluxes with high spatio-temporal resolutions.
    Description: This work was supported by a grant from IODP Exp. 346 After Cruise Research Program, JAMSTEC, awarded to TR, IK, Irino T, Itaki T, ST, KY, SS, and KA and from JSPS KAKENHI grant number 16H01765 awarded to TR.
    Keywords: Quaternary sediments ; Japan Sea ; Inter-site correlation ; High-resolution age model ; IODP ; Expedition 346 ; U1424 ; U1425 ; U1426 ; U1430
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Remote Sensing of Environment 217 (2018): 126-143, doi:10.1016/j.rse.2018.08.010.
    Description: Diatoms dominate global silica production and export production in the ocean; they form the base of productive food webs and fisheries. Thus, a remote sensing algorithm to identify diatoms has great potential to describe ecological and biogeochemical trends and fluctuations in the surface ocean. Despite the importance of detecting diatoms from remote sensing and the demand for reliable methods of diatom identification, there has not been a systematic evaluation of algorithms that are being applied to this end. The efficacy of these models remains difficult to constrain in part due to limited datasets for validation. In this study, we test a bio-optical algorithm developed by Sathyendranath et al. (2004) to identify diatom dominance from the relationship between ratios of remote sensing reflectance and chlorophyll concentration. We evaluate and refine the original model with data collected at the Martha's Vineyard Coastal Observatory (MVCO), a near-shore location on the New England shelf. We then validated the refined model with data collected in Harpswell Sound, Maine, a site with greater optical complexity than MVCO. At both sites, despite relatively large changes in diatom fraction (0.8–82% of chlorophyll concentration), the magnitude of variability in optical properties due to the dominance or non-dominance of diatoms is less than the variability induced by other absorbing and scattering constituents of the water. While the original model performance was improved through successive re-parameterizations and re-formulations of the absorption and backscattering coefficients, we show that even a model originally parameterized for the Northwest Atlantic and re-parameterized for sites such as MVCO and Harpswell Sound performs poorly in discriminating diatom-dominance from optical properties.
    Description: This work was supported by: a Woods Hole Oceanographic Institution Summer Student Fellowship (NSF REU award #1156952) and a Bowdoin College Grua/O'Connell Research Award to SJK; grants to HMS from NASA (Ocean Biology and Biogeochemistry program and Biodiversity and Ecological Forecasting program), NSF (Ocean Sciences), the Gordon and Betty Moore Foundation, the Simons Foundation, and NOAA through the Cooperative Institute for the North Atlantic Region (CINAR) under Cooperative Agreement NA14OAR4320158; and grants to CSR from NASA (Ocean Biology and Biogeochemistry program).
    Keywords: Phytoplankton ; Community structure ; Ocean color ; Diatoms
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Regional Studies in Marine Science 24 (2018): 336-342, doi:10.1016/j.rsma.2018.09.006.
    Description: The variations of sea level over the Red Sea may be divided into three broad categories: tidal, seasonal and weather-band. Our study employs a variety of in situ and satellite-derived data in the first comprehensive examination of the Red Sea water level variations in the weather-band (covering periods of 4–30 days). In the central Red Sea, the range of the weather-band sea level signal is of order 0.7 m, which exceeds the tidal and seasonal sea level ranges. From EOF and correlation analysis, we find that a large fraction of the weather-band sea level variation is due to a single mode of motion that extends over the entire Red Sea. In this mode, the water level rises and falls in unison with an amplitude that declines going southward over the southern Red Sea. The temporal signal of this mode is highly correlated with the along-axis surface wind stress over the southern Red Sea, and is closely reproduced by a simple one-dimensional barotropic model with forcing by the along-axis wind stress. Although this model does not account for the full suite of dynamics affecting weather-band sea level variations in the Red Sea, it may serve as a useful predictive tool. Sea level changes associated with the development and movement of sub-mesoscale features (e.g., eddies and boundary currents) are also shown to contribute to weather-band sea level motions in the Red Sea.
    Description: The pressure sensor and meteorological buoy data were acquired as part of a program supported by Award Nos. USA00001, USA00002 and KSA00011 made by KAUST to WHOI. The data analysis and modeling work of this study were supported General Commission for Survey (GCS), under a project number RGC/3/1612-01-01 made by Office of Sponsored research (ORS)/KAUST, Kingdom of Saudi Arabia.
    Keywords: Red Sea water levels ; Wind-driven sea level variations
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Publication Date: 2022-05-25
    Description: This paper is not subject to U.S. copyright. The definitive version was published in Global and Planetary Change 167 (2018): 1-23, doi:10.1016/j.gloplacha.2018.04.004.
    Description: A compilation of foraminiferal stable isotope measurements from southern high latitude (SHL) deep-sea sites provides a novel perspective important for understanding Earth's paleotemperature and paleoceanographic changes across the rise and fall of the Cretaceous Hot Greenhouse climate and the subsequent Paleogene climatic optimum. Both new and previously published results are placed within an improved chronostratigraphic framework for southern South Atlantic and southern Indian Ocean sites. Sites studied were located between 58° and 65°S paleolatitude and were deposited at middle to upper bathyal paleodepths. Oxygen isotope records suggest similar trends in both bottom and surface water temperatures in the southern sectors of the South Atlantic and in the Indian Ocean basins. Warm conditions were present throughout the Albian, extreme warmth existed during the Cretaceous Thermal Maximum (early-mid-Turonian) through late Santonian, and long-term cooling began in the Campanian and culminated in Cretaceous temperature minima during the Maastrichtian. Gradients between surface and seafloor δ18O and δ13C values were unusually high throughout the 11.5 m.y. of extreme warmth during the Turonian-early Campanian, but these vertical gradients nearly disappeared by the early Maastrichtian. In absolute terms, paleotemperature estimates that use standard assumptions for pre-glacial seawater suggest sub-Antarctic bottom waters were ≥21 °C and sub-Antarctic surface waters were ≥27 °C during the Turonian, values warmer than published climate models support. Alternatively, estimated temperatures can be reduced to the upper limits of model results through freshening of high latitude waters but only if there were enhanced precipitation of water with quite low δ18O values. Regardless, Turonian planktonic δ18O values are ~1.5‰ lower than minimum values reported for the Paleocene-Eocene Thermal Maximum (PETM) from the same region, a difference which corresponds to Turonian surface temperatures ~6 °C warmer than peak PETM temperatures if Turonian and Paleocene temperatures are estimated using the same assumptions. It is likely that warm oceans surrounding and penetrating interior Antarctica (given higher relative sea level) prevented growth of Antarctic ice sheets at all but the highest elevations from the late Aptian through late Campanian; however, Maastrichtian temperatures may have been cool enough to allow growth of small, ephemeral ice sheets. The standard explanation for the sustained warmth during Cretaceous Hot Greenhouse climate invokes higher atmospheric CO2 levels from volcanic outgassing, but correlation among temperature estimates, proxy estimates of pCO2, and intervals of high fluxes of both mafic and silicic volcanism are mostly poor. This comparison demonstrates that the relative timing between events and their putative consequences need to be better constrained to test and more fully understand relationships among volcanism, pCO2, temperature ocean circulation, Earth's biota and the carbon cycle.
    Description: Funding from the Smithsonian National Museum of Natural History and the National Science Foundation (NSF-OCE 1261586) helped support this research.
    Keywords: Cretaceous Hot Greenhouse ; Foraminiferal stable isotopes ; Volcanic outgassing ; pCO2 proxies ; Greenhouse glacier hypothesis ; Southern high latitudes
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Chemical Geology 493 (2018): 210-223, doi:10.1016/j.chemgeo.2018.05.040.
    Description: The GEOTRACES Intermediate Data Product 2017 (IDP2017) is the second publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2016. The IDP2017 includes data from the Atlantic, Pacific, Arctic, Southern and Indian oceans, with about twice the data volume of the previous IDP2014. For the first time, the IDP2017 contains data for a large suite of biogeochemical parameters as well as aerosol and rain data characterising atmospheric trace element and isotope (TEI) sources. The TEI data in the IDP2017 are quality controlled by careful assessment of intercalibration results and multi-laboratory data comparisons at crossover stations. The IDP2017 consists of two parts: (1) a compilation of digital data for more than 450 TEIs as well as standard hydrographic parameters, and (2) the eGEOTRACES Electronic Atlas providing an on-line atlas that includes more than 590 section plots and 130 animated 3D scenes. The digital data are provided in several formats, including ASCII, Excel spreadsheet, netCDF, and Ocean Data View collection. Users can download the full data packages or make their own custom selections with a new on-line data extraction service. In addition to the actual data values, the IDP2017 also contains data quality flags and 1-σ data error values where available. Quality flags and error values are useful for data filtering and for statistical analysis. Metadata about data originators, analytical methods and original publications related to the data are linked in an easily accessible way. The eGEOTRACES Electronic Atlas is the visual representation of the IDP2017 as section plots and rotating 3D scenes. The basin-wide 3D scenes combine data from many cruises and provide quick overviews of large-scale tracer distributions. These 3D scenes provide geographical and bathymetric context that is crucial for the interpretation and assessment of tracer plumes near ocean margins or along ridges. The IDP2017 is the result of a truly international effort involving 326 researchers from 25 countries. This publication provides the critical reference for unpublished data, as well as for studies that make use of a large cross-section of data from the IDP2017. This article is part of a special issue entitled: Conway GEOTRACES - edited by Tim M. Conway, Tristan Horner, Yves Plancherel, and Aridane G. González.
    Description: We gratefully acknowledge financial support by the Scientific Committee on Oceanic Research (SCOR) through grants from the U.S. National Science Foundation, including grants OCE-0608600, OCE-0938349, OCE-1243377, and OCE-1546580. Financial support was also provided by the UK Natural Environment Research Council (NERC), the Ministry of Earth Science of India, the Centre National de Recherche Scientifique, l'Université Paul Sabatier de Toulouse, the Observatoire Midi-Pyrénées Toulouse, the Universitat Autònoma de Barcelona, the Kiel Excellence Cluster The Future Ocean, the Swedish Museum of Natural History, The University of Tokyo, The University of British Columbia, The Royal Netherlands Institute for Sea Research, the GEOMAR-Helmholtz Centre for Ocean Research Kiel, and the Alfred Wegener Institute.
    Keywords: GEOTRACES ; Trace elements ; Isotopes ; Electronic atlas ; IDP2017
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2022-05-25
    Description: This paper is not subject to U.S. copyright. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 152 (2018): 67-81, doi:10.1016/j.dsr2.2018.05.020.
    Description: Ocean acidification (OA), driven by rising anthropogenic carbon dioxide (CO2), is rapidly advancing in the Pacific Arctic Region (PAR), producing conditions newly corrosive to biologically important carbonate minerals like aragonite. Naturally short linkages across the PAR food web mean that species-specific acidification stress can be rapidly transmitted across multiple trophic levels, resulting in widespread impacts. Therefore, it is critical to understand the formation, transport, and persistence of acidified conditions in the PAR in order to better understand and project potential impacts to this delicately balanced ecosystem. Here, we synthesize data from process studies across the PAR to show the formation of corrosive conditions in colder, denser winter-modified Pacific waters over shallow shelves, resulting from the combination of seasonal terrestrial and marine organic matter respiration with anthropogenic CO2. When these waters are subsequently transported off the shelf, they acidify the Pacific halocline. We estimate that Barrow Canyon outflow delivers ~2.24 Tg C yr-1 to the Arctic Ocean through corrosive winter water transport. This synthesis also allows the combination of spatial data with temporal data to show the persistence of these conditions in halocline waters. For example, one study in this synthesis indicated that 0.5–1.7 Tg C yr-1 may be returned to the atmosphere via air-sea gas exchange of CO2 during upwelling events along the Beaufort Sea shelf that bring Pacific halocline waters to the ocean surface. The loss of CO2 during these events is more than sufficient to eliminate corrosive conditions in the upwelled Pacific halocline waters. However, corresponding moored and discrete data records indicate that potentially corrosive Pacific waters are present in the Beaufort shelfbreak jet during 80% of the year, indicating that the persistence of acidified waters in the Pacific halocline far outweighs any seasonal mitigation from upwelling. Across the datasets in this large-scale synthesis, we estimate that the persistent corrosivity of the Pacific halocline is a recent phenomenon that appeared between 1975 and 1985. Over that short time, these potentially corrosive waters originating over the continental shelves have been observed as far as the entrances to Amundsen Gulf and M’Clure Strait in the Canadian Arctic Archipelago. The formation and transport of corrosive waters on the Pacific Arctic shelves may have widespread impact on the Arctic biogeochemical system and food web reaching all the way to the North Atlantic.
    Description: National Science Foundation Grant PLR-1303617.
    Keywords: Ocean acidification ; Pacific Arctic ; Arctic Ocean ; East Siberian Sea ; Chukchi Sea ; Beaufort Sea ; Transport ; Arctic Rivers ; Sea Ice ; Respiration ; Upwelling ; Biological vulnerability ; Community resilience
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Progress in Earth and Planetary Science 5 (2018): 74, doi:10.1186/s40645-018-0232-3.
    Description: South Chamorro Seamount (SCS) is a blueschist-bearing serpentinite mud volcano in the Mariana forearc. Previous scientific drilling conducted at SCS revealed highly alkaline, sulfate-rich formation fluids resulting from slab-derived fluid upwelling combined with serpentinization both beneath and within the seamount. In the present study, a time-series of ROV dives spanning 1000 days was conducted to collect discharging alkaline fluids from the cased Ocean Drilling Program (ODP) Hole 1200C (hereafter the CORK fluid). The CORK fluids were analyzed for chemical compositions (including dissolved gas) and microbial community composition/function. Compared to the ODP porewater, the CORK fluids were generally identical in concentration of major ions, with the exception of significant sulfate depletion and enrichment in sulfide, alkalinity, and methane. Microbiological analyses of the CORK fluids revealed little biomass and functional activity, despite habitable temperature conditions. The post-drilling sulfate depletion is likely attributable to sulfate reduction coupled with oxidation of methane (and hydrogen), probably triggered by the drilling and casing operations. Multiple lines of evidence suggest that abiotic organic synthesis associated with serpentinization is the most plausible source of the abundant methane in the CORK fluid. The SCS formation fluid regime presented here may represent the first example on Earth where abiotic syntheses are conspicuous with little biotic processes, despite a condition with sufficient bioavailable energy potentials and temperatures within the habitable range.
    Description: This work was partly supported by JSPS KAKENHI Grant Number 25701004 (SK).
    Keywords: Forearc serpentinite mud volcano ; South Chamorro Seamount ; Limit of biosphere ; Present-days’ chemical evolution ; Radio-isotope-tracer carbon assimilation estimation
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Remote Sensing of Environment 209 (2018): 677-699, doi:10.1016/j.rse.2018.02.075.
    Description: We analyse ten years of QuikSCAT satellite surface winds to statistically characterize the spatio-temporal variability of the westward mountain-gap wind jets over the northern Red Sea. These wind jets bring relatively cold and dry air from the Arabian Desert, increasing heat loss and evaporation over the region similar to cold-air outbreaks from mid and subpolar latitudes. QuikSCAT captures the spatial structure of the wind jets and agrees well with in situ observations from a heavily instrumented mooring in the northern Red Sea. The local linear correlations between QuikSCAT and in situ winds are 0.96 (speed) and 0.85 (direction). QuikSCAT also reveals that cross-axis winds such as the mountain-gap wind jets are a major component of the regional wind variability. The cross-axis wind pattern appears as the second (or third) mode in the four vector Empirical Orthogonal Function analyses we performed, explaining between 6% to 11% of the wind variance. Westward wind jets are typical in winter, especially in December and January, but with strong interannual variability. Several jets can occur simultaneously and cover a large latitudinal range of the northern Red Sea, which we call large-scale westward events. QuikSCAT recorded 18 large-scale events over ten years, with duration between 3 to 8 days and strengths varying from 3–4 to 9–10 m/s. These events cause large changes in the wind stress curl pattern, imposing a remarkable sequence of positive and negative curl along the Red Sea main axis, which might be a wind forcing mechanism for the oceanic mesoscale circulation.
    Description: This work was supported by NSF grant OCE-1435665 and NASA grant NNX14AM71G.
    Keywords: QuikSCAT ; Air-sea interaction ; Wind jets ; Mountain gap ; Evaporation ; Heat loss
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Publication Date: 2022-05-25
    Description: This paper is not subject to U.S. copyright. The definitive version was published in Coastal Engineering 136 (2018): 147-160, doi:10.1016/j.coastaleng.2018.01.003.
    Description: The performance of a linear depth inversion algorithm, cBathy, applied to coastal video imagery was assessed using observations of water depth from vessel-based hydrographic surveys and in-situ altimeters for a wide range of wave conditions (0.3 〈 significant wave height 〈 4.3 m) on a sandy Atlantic Ocean beach near Duck, North Carolina. Comparisons of video-based cBathy bathymetry with surveyed bathymetry were similar to previous studies (root mean square error (RMSE) = 0.75 m, bias = −0.26 m). However, the cross-shore locations of the surfzone sandbar in video-derived bathymetry were biased onshore 18–40 m relative to the survey when offshore wave heights exceeded 1.2 m or were greater than half of the bar crest depth, and broke over the sandbar. The onshore bias was 3–4 m when wave heights were less than 0.8 m and were not breaking over the sandbar. Comparisons of video-derived seafloor elevations with in-situ altimeter data at three locations onshore of, near, and offshore of the surfzone sandbar over ∼1 year provide the first assessment of the cBathy technique over a wide range of wave conditions. In the outer surf zone, video-derived results were consistent with long-term patterns of bathymetric change (r2 = 0.64, RMSE = 0.26 m, bias = −0.01 m), particularly when wave heights were less than 1.2 m (r2 = 0.83). However, during storms when wave heights exceeded 3 m, video-based cBathy over-estimated the depth by up to 2 m. Near the sandbar, the sign of depth errors depended on the location relative to wave breaking, with video-based depths overestimated (underestimated) offshore (onshore) of wave breaking in the surfzone. Wave speeds estimated by video-based cBathy at the initiation of wave breaking often were twice the speeds predicted by linear theory, and up to three times faster than linear theory during storms. Estimated wave speeds were half as fast as linear theory predictions at the termination of wave breaking shoreward of the sandbar. These results suggest that video-based cBathy should not be used to track the migration of the surfzone sandbar using data when waves are breaking over the bar nor to quantify morphological evolution during storms. However, these results show that during low energy conditions, cBathy estimates could be used to quantify seasonal patterns of seafloor evolution.
    Description: This research was funded by the U.S. Army Corps of Engineers Coastal Field Data Collection Program, the Deputy Assistant Secretary of the Army for Research and Technology under ERDC's research program titled “Force Projection Entry Operations, STO D.GRD.2015.34”, the U.S. Naval Research Laboratory base program from the Office of Naval Research, a Vannevar Bush Faculty Fellowship funded by the Assistant Secretary of Defense for Research and Engineering, and the National Science Foundation.
    Keywords: Remote sensing ; Beach morphology ; Depth inversion ; Bathymetry estimation ; Video imaging ; Surfzone
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Geochimica et Cosmochimica Acta 228 (2018): 95-118, doi:10.1016/j.gca.2018.01.021.
    Description: Hosted in basaltic substrate on the ultra-slow spreading Mid-Cayman Rise, the Piccard hydrothermal field is the deepest currently known seafloor hot-spring (4957–4987 m). Due to its great depth, the Piccard site is an excellent natural system for investigating the influence of extreme pressure on the formation of submarine vent fluids. To investigate the role of rock composition and deep circulation conditions on fluid chemistry, the abundance and isotopic composition of organic, inorganic, and dissolved volatile species in high temperature vent fluids at Piccard were examined in samples collected in 2012 and 2013. Fluids from the Beebe Vents and Beebe Woods black smokers vent at a maximum temperature of 398 °C at the seafloor, however several lines of evidence derived from inorganic chemistry (Cl, SiO2, Ca, Br, Fe, Cu, Mn) support fluid formation at much higher temperatures in the subsurface. These high temperatures, potentially in excess of 500 °C, are attainable due to the great depth of the system. Our data indicate that a single deep-rooted source fluid feeds high temperature vents across the entire Piccard field. High temperature Piccard fluid H2 abundances (19.9 mM) are even higher than those observed in many ultramafic-influenced systems, such as the Rainbow (16 mM) and the Von Damm hydrothermal fields (18.2 mM). In the case of Piccard, however, these extremely high H2 abundances can be generated from fluid-basalt reaction occurring at very high temperatures. Magmatic and thermogenic sources of carbon in the high temperature black smoker vents are described. Dissolved ΣCO2 is likely of magmatic origin, CH4 may originate from a combination of thermogenic sources and leaching of abiotic CH4 from mineral-hosted fluid inclusions, and CO abundances are at equilibrium with the water–gas shift reaction. Longer-chained n-alkanes (C2H6, C3H8, n-C4H10, i-C4H10) may derive from thermal alteration of dissolved and particulate organic carbon sourced from the original seawater source, entrainment of microbial ecosystems peripheral to high temperature venting, and/or abiotic mantle sources. Dissolved ΣHCOOH in the Beebe Woods fluid is consistent with thermodynamic equilibrium for abiotic production via ΣCO2 reduction with H2 at 354 °C measured temperature. A lack of ΣHCOOH in the relatively higher temperature 398 °C Beebe Vent fluids demonstrates the temperature sensitivity of this equilibrium. Abundant basaltic seafloor outcrops and the axial location of the vent field, along with multiple lines of geochemical evidence, support extremely high temperature fluid-rock reaction with mafic substrate as the dominant control on Piccard fluid chemistry. These results expand the known diversity of vent fluid composition, with implications for supporting microbiological life in both the modern and ancient ocean.
    Description: This work was supported by the National Aeronautics and Space Administration (NASA) Astrobiology Science and Technology for Exploring Planets program [award number NNX09AB75G to CRG and JSS]; and the National Science Foundation [award number OCE-1061863 to CRG and JSS].
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Earth and Planetary Science Letters 487 (2018): 165-178, doi:10.1016/j.epsl.2018.01.032.
    Description: A new geospeedometer is developed based on the differential closures of Mg and rare earth element (REE) bulk-diffusion between coexisting plagioclase and clinopyroxene. By coupling the two elements with distinct bulk closure temperatures, this speedometer can numerically solve the initial temperatures and cooling rates for individual rock samples. As the existing Mg-exchange thermometer was calibrated for a narrow temperature range and strongly relies on model-dependent silica activities, a new thermometer is developed using literature experimental data. When the bulk closure temperatures of Mg and REE are determined, respectively, using this new Mg-exchange thermometer and the existing REE-exchange thermometer, this speedometer can be implemented for a wide range of compositions, mineral modes, and grain sizes. Applications of this new geospeedometer to oceanic gabbros from the fast-spreading East Pacific Rise at Hess Deep reveal that the lower oceanic crust crystallized at temperatures of 998–1353 °C with cooling rates of 0.003–10.2 °C/yr. Stratigraphic variations of the cooling rates and crystallization temperatures support deep hydrothermal circulations and in situ solidification of various replenished magma bodies. Together with existing petrological, geochemical and geophysical evidence, results from this new speedometry suggest that the lower crust formation at fast-spreading mid-ocean ridges involves emplacement of primary mantle melts in the deep section of the crystal mush zone coupled with efficient heat removal by crustal-scale hydrothermal circulations. The replenished melts become chemically and thermally evolved, accumulate as small magma bodies at various depths, feed the shallow axial magma chamber, and may also escape from the mush zone to generate off-axial magma lenses.
    Description: C. Sun acknowledges support from the Devonshire postdoctoral scholarship at WHOI and NSF grant OCE-1637130. This work was also supported by Natural Environment Research Council (NERC) Grant NE/I001670/1 to J. Lissenberg.
    Keywords: Oceanic crust ; Cooling rate ; Crystallization temperature ; Plagioclase ; Clinopyroxene ; Hess Deep
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Publication Date: 2022-05-25
    Description: This paper is not subject to U.S. copyright. The definitive version was published in Marine and Petroleum Geology 19 (2002): 971-987, doi:10.1016/S0264-8172(02)00132-0.
    Description: Considerable crustal thickness variations are inferred along Cayman Trough, a slow-spreading ocean basin in the Caribbean Sea, from modeling of the gravity field. The crust to a distance of 50 km from the spreading center is only 2–3 km thick in agreement with dredge and dive results. Crustal thickness increases to ∼5.5 km at distances between 100 and 430 km west of the spreading center and to 3.5–6 km at distances between 60 and 370 km east of the spreading center. The increase in thickness is interpreted to represent serpentinization of the uppermost mantle lithosphere, rather than a true increase in the volume of accreted ocean crust. Serpentinized peridotite rocks have indeed been dredged from the base of escarpments of oceanic crust rocks in Cayman Trough. Laboratory-measured density and P-wave speed of peridotite with 40–50% serpentine are similar to the observed speed in published refraction results and to the inferred density from the model. Crustal thickness gradually increases to 7–8 km at the far ends of the trough partially in areas where sea floor magnetic anomalies were identified. Basement depth becomes gradually shallower starting 250 km west of the rise and 340 km east of the rise, in contrast to the predicted trend of increasing depth to basement from cooling models of the oceanic lithosphere. The gradual increase in apparent crustal thickness and the shallowing trend of basement depth are interpreted to indicate that the deep distal parts of Cayman Trough are underlain by highly attenuated crust, not by a continuously accreted oceanic crust.
    Description: DFC was partly supported by NSF grant EAR-92-19796.
    Keywords: Caribbean plate ; Cayman trough ; Continental margins ; Gravity anomalies ; Serpentinized peridotite ; Slow spreading
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marine Chemistry 206 (2018): 7-18, doi:10.1016/j.marchem.2018.08.005.
    Description: The lateral export of carbon from coastal marshes via tidal exchange is a key component of the marsh carbon budget and coastal carbon cycles. However, the magnitude of this export has been difficult to accurately quantify due to complex tidal dynamics and seasonal cycling of carbon. In this study, we use in situ, high-frequency measurements of dissolved inorganic carbon (DIC) and water fluxes to estimate lateral DIC fluxes from a U.S. northeastern salt marsh. DIC was measured by a CHANnelized Optical Sensor (CHANOS) that provided an in situ concentration measurement at 15-min intervals, during periods in summer (July – August) and late fall (December). Seasonal changes in the marsh had strong effects on DIC concentrations, while tidally-driven water fluxes were the fundamental vehicle of marsh carbon export. Episodic events, such as groundwater discharge and mean sea water level changes, can impact DIC flux through altered DIC concentrations and water flow. Variability between individual tides within each season was comparable to mean variability between the two seasons. Estimated mean DIC fluxes based on a multiple linear regression (MLR) model of DIC concentrations and high-frequency water fluxes agreed reasonably well with those derived from CHANOS DIC measurements for both study periods, indicating that high-frequency, modeled DIC concentrations, coupled with continuous water flux measurements and a hydrodynamic model, provide a robust estimate of DIC flux. Additionally, an analysis of sampling strategies revealed that DIC fluxes calculated using conventional sampling frequencies (hourly to two-hourly) of a single tidal cycle are unlikely to capture a representative mean DIC flux compared to longer-term measurements across multiple tidal cycles with sampling frequency on the order of tens of minutes. This results from a disproportionately large amount of the net DIC flux occurring over a small number of tidal cycles, while most tides have a near-zero DIC export. Thus, high-frequency measurements (on the order of tens of minutes or better) over the time period of interest are necessary to accurately quantify tidal exports of carbon species from salt marshes.
    Description: This work was funded by NSF Graduate Research Fellowship Program, NSF Ocean Sciences Postdoctoral Fellowship (OCE-1323728), Link FoundationOcean Engineering and Instrumentation Fellowship, National Institute of Science and Technology (NIST no. 60NANB10D024), the USGS LandCarbon and Coastal & Marine Geology Programs, NSF Chemical Oceanography Program (OCE-1459521), NSF Ocean Technology and Interdisciplinary Coordination program (OCE-1233654) and NOAA Science Collaborative (NA09NOS4190153).
    Keywords: Dissolved inorganic carbon ; Carbon export ; Salt marshes ; Wetlands
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of the History of Biology 51 (2018): 693–805, doi:10.1007/s10739-018-9538-7.
    Description: The Bermuda Principles for DNA sequence data sharing are an enduring legacy of the Human Genome Project (HGP). They were adopted by the HGP at a strategy meeting in Bermuda in February of 1996 and implemented in formal policies by early 1998, mandating daily release of HGP-funded DNA sequences into the public domain. The idea of daily sharing, we argue, emanated directly from strategies for large, goal-directed molecular biology projects first tested within the “community” of C. elegans researchers, and were introduced and defended for the HGP by the nematode biologists John Sulston and Robert Waterston. In the C. elegans community, and subsequently in the HGP, daily sharing served the pragmatic goals of quality control and project coordination. Yet in the HGP human genome, we also argue, the Bermuda Principles addressed concerns about gene patents impeding scientific advancement, and were aspirational and flexible in implementation and justification. They endured as an archetype for how rapid data sharing could be realized and rationalized, and permitted adaptation to the needs of various scientific communities. Yet in addition to the support of Sulston and Waterston, their adoption also depended on the clout of administrators at the US National Institutes of Health (NIH) and the UK nonprofit charity the Wellcome Trust, which together funded 90% of the HGP human sequencing effort. The other nations wishing to remain in the HGP consortium had to accommodate to the Bermuda Principles, requiring exceptions from incompatible existing or pending data access policies for publicly funded research in Germany, Japan, and France. We begin this story in 1963, with the biologist Sydney Brenner’s proposal for a nematode research program at the Laboratory of Molecular Biology (LMB) at the University of Cambridge. We continue through 2003, with the completion of the HGP human reference genome, and conclude with observations about policy and the historiography of molecular biology.
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Publication Date: 2022-05-25
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Climate Dynamics 51 (2018): 3275–3289, doi:10.1007/s00382-018-4078-6.
    Description: The atmospheric jet and blocking distributions, especially in the North Atlantic sector, have been challenging features for a climate model to realistically reproduce. This study examines climatological distributions of winter (December–February) daily jet latitude and blocking in the North Atlantic from the 40-member Community Earth System Model version 1 Large Ensemble (CESM1LE) simulations. This analysis aims at examining whether a broad range of internal climate variability encompassed by a large ensemble of simulations results in an improved representation of the jet latitude distributions and blocking days in CESM1LE. In the historical runs (1951–2005), the daily zonal wind at 850 hPa exhibits three distinct preferred latitudes for the eddy-driven jet position as seen in the reanalysis datasets, which represents a significant improvement from the previous version of the same model. However, the meridional separations between the three jet latitudes are much smaller than those in the reanalyses. In particular, the jet rarely migrates to the observed southernmost position around 37°N. This leads to the bias in blocking frequency that is too low over Greenland and too high over the Azores. These features are shown to be remarkably stable across the 40 ensemble members with negligible member-to-member spread. This result implies the range of internal variability of winter jet latitude and blocking frequency within the 55-year segment from each ensemble member is comparable to that represented by the full large ensemble. Comparison with 2046–2100 from the RCP8.5 future projection runs suggests that the daily jet position is projected to maintain the same three preferred latitudes, with a slightly higher frequency of occurrence over the central latitude around 50°N, instead of shifting poleward in the future as documented in some previous studies. In addition, the daily jet speed is projected not to change significantly between 1951–2005 and 2046–2100. On the other hand, the climatological mean jet is projected to become slightly more elongated and stronger on its southern flank, and the blocking frequency over the Azores is projected to decrease.
    Description: Authors gratefully acknowledge support from the UCAR Significant Opportunities in Atmospheric Research and Science (SOARS) and WHOI Summer Student Fellowship programs. AC and CM were supported in part by the SOARS program, NSF Grant AGS- 1120459. In addition, the supports by the NSF AGS Climate and Largescale Dynamics program and OCE Physical Oceanography program (AGS-1355339) to Y-OK and HS, the DOE BER Regional and Global Climate Modeling program (DE-SC0014433) to Y-OK, and the NSF EaSM3 Sustainability Research Networks program (OCE-1419235) to HS are acknowledged.
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Publication Date: 2022-05-25
    Description: This paper is not subject to U.S. copyright. The definitive version was published in Marine Geology 337 (2013): 53-66, doi:10.1016/j.margeo.2013.01.005.
    Description: Submarine canyons are common features of continental margins worldwide. They are conduits that funnel vast quantities of sediment from the continents to the deep sea. Though it is known that submarine canyons form primarily from erosion induced by submarine sediment flows, we currently lack quantitative, empirically based expressions that describe the morphology of submarine canyon networks. Multibeam bathymetry data along the entire passive US Atlantic margin (USAM) and along the active central California margin near Monterey Bay provide an opportunity to examine the fine-scale morphology of 171 slope-sourced canyons. Log–log regression analyses of canyon thalweg gradient (S) versus up-canyon catchment area (A) are used to examine linkages between morphological domains and the generation and evolution of submarine sediment flows. For example, canyon reaches of the upper continental slope are characterized by steep, linear and/or convex longitudinal profiles, whereas reaches farther down canyon have distinctly concave longitudinal profiles. The transition between these geomorphic domains is inferred to represent the downslope transformation of debris flows into erosive, canyon-flushing turbidity flows. Over geologic timescales this process appears to leave behind a predictable geomorphic fingerprint that is dependent on the catchment area of the canyon head. Catchment area, in turn, may be a proxy for the volume of sediment released during geomorphically significant failures along the upper continental slope. Focused studies of slope-sourced submarine canyons may provide new insights into the relationships between fine-scale canyon morphology and down-canyon changes in sediment flow dynamics.
    Keywords: Turbidity flow ; Debris flow ; Multibeam bathymetry ; Regression ; Power law ; Landslide
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Publication Date: 2020-03-09
    Description: Stream chemistry reflects the mixture of complex biogeochemical reactions that vary across space and time within watersheds. For example, streams experience changing hydrologic connectivity to heterogeneous water sources under different flow regimes; however, it remains unclear how seasonal flow paths link these different sources and regulate concentration-discharge behavior, i.e., changes in stream solute concentration as a function of discharge. At the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) in central Pennsylvania, USA, concentrations of chemostatic solutes (K, Mg, Na, Si, Cl) vary little across a wide range of discharge values while concentrations of chemodynamic solutes (Fe, Mn, Ca) decrease sharply with increasing stream discharge. To elucidate controls on chemodynamic solute behavior, we investigated the chemistry of surface water and shallow subsurface water at the SSHCZO in early autumn when discharge was negligible and concentrations of chemodynamic solutes were high. Dissolved ions, colloids, and micron-sized particles were extracted from hillslope soils and stream sediments to evaluate how elements were mobilized into pore waters and transported from hillslopes to the stream. During the study period when flow was intermittent, the stream consisted of isolated puddles that were chemically variable along the length of the channel. Inputs of subsurface water to the stream were limited to an area of upwelling near the stream headwaters, and the water table remained over a meter below the stream bed along the rest of the channel. Chemodynamic elements Fe and Mn were preferentially mobilized from organic-rich soils as a mixture of dissolved ions, colloids, and micron-sized particles; consequently, subsurface water draining organic-rich soils in the upper catchment was enriched in Fe and Mn. Conversely, Ca increased towards the catchment outlet and was primarily mobilized from stream sediments as Ca2+. Concentrations of chemostatic solutes were relatively invariable throughout the catchment. We conclude that chemodynamic behavior at SSHCZO is driven by seasonally variable connectivity between the stream and hillslope soils. During the dry season, stream water derives from a shallow perched water table (interflow) that upwells to generate metal-rich stream headwaters. High concentrations of soluble Fe and Mn at low discharge occur when metal-rich headwaters are flushed to the catchment outlet during periodic rain events. Interflow during the dry season originates from water that infiltrates through organic-rich swales; thus, metals in the stream at low flow are ultimately derived from convergent hillslopes where biological processes have concentrated and/or mobilized these chemodynamic elements. In contrast, high concentrations of Ca2+ at low discharge are likely mobilized from stream sediments that contain secondary calcite precipitates. We infer that chemodynamic solutes are diluted at high discharge primarily due to increased flow through planar hillslopes. This study highlights how spatially heterogeneous biogeochemistry and seasonally variable flow paths regulate concentration-discharge behavior within catchments.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3YOUMARES 8 – Oceans Across Boundaries: Learning from each other, YOUMARES 8 – Oceans Across Boundaries: Learning from each other, Cham, Springer, 6 p., pp. 1-6, ISBN: 978-3-319-93284-2
    Publication Date: 2020-06-12
    Description: YOUMARES is an annual early-career scientist conference series. It is an initiative of the German Society for Marine Research (DGM) and takes place in changing cities of northern Germany. The conference series is organized in a bottom-up structure: from and for YOUng MARine RESearchers. In this chapter, we describe the concept of YOUMARES together with its historical development from a single-person initiative to a conference venue of about 200 participants. Furthermore, the three authors added some personals experiences and insights, what YOUMARES means to them.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Publication Date: 2022-05-24
    Description: Is Europe-wide operational earthquake forecasting (OEF) possible? We discuss the myriad problems that prevent it today, many of which relate to heterogeneities in earthquake recording, processing, and reporting. We contemplate the difficulty of building models that cross political boundaries, and we consider the prospect of European OEF in light of recent efforts to harmonize long-term seismic hazard assessment among several nations. Emphasizing the Strategies and Tools for Real-time Earthquake Risk Reduction (REAKT) project, we report achievements related to short-term seismicity forecasting in Iceland and Italy that could apply elsewhere in Europe. In Iceland, collaboration fostered by REAKT resulted in a revised earthquake catalog and a prototype OEF system. We report results from an experiment conducted with this prototype; these results suggest ensemble models provide an information gain, updating models more frequently improves their forecast skill, and that OEF is computationally feasible. In Italy, REAKT supported the creation of an ensemble model that now issues weekly hazard forecasts. We present examples of these forecasts, highlighting the problem that OEF often yields low probabilities, which are difficult to interpret and convert into actionable decisions. Motivated by such low hazard probabilities, we highlight Europe’s pioneering efforts in operational earthquake loss forecasting and mention solutions to problems that currently prevent OEF at the European scale.
    Description: Published
    Description: 2459-2469
    Description: 5T. Modelli di pericolosità sismica e da maremoto
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Publication Date: 2022-05-24
    Description: Investigating relationships between macroseismic intensity and strong-motion data requires the existence of these two records for the same seismic event and site. In Italy, this comparison is feasible through the cross-matching of the Italian Macroseismic Database (DBMI) and the Italian Strong-Motion Database (ITACA) which are the most comprehensive sources of both data. However, the two databases lack a direct link which would allow performing joint analysis of macroseismic data points and strong-motion recordings, making the comparison a time consuming job for the researcher. This paper demonstrates the usefulness of cross-database identifiers, and presents their use in a webtool called Rosetta, an initial proof-of-concept that helped testing linking procedures among DBMI and ITACA, and user friendly visual solutions. The development allowed the working group to exchange expertise on their respective database structures and workflows, laying the groundwork for a consistent, low-maintenance, and durable solution that will be easily updatable each time a new version of DBMI or ITACA will be released.
    Description: Italian Department of Civil Protection to the project INGV-DPC S2-2014 “Constraining Observations into Seismic Hazard”
    Description: Published
    Description: 2429–2443
    Description: 3T. Storia Sismica
    Description: 4T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Description: 4IT. Banche dati
    Description: JCR Journal
    Keywords: seismology ; macroseismic intensity ; strong-motion ; stations ; historical earthquakes ; database ; identifiers ; 04.06. Seismology ; 05.02. Data dissemination
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Publication Date: 2022-06-06
    Description: A network of shear zones that evolved through the brittle-ductile transition is exposed in the Calamita Schists, Elba Island, Italy. The shear zones formed during Late Miocene contractional deformation coeval with high grade contact metamorphism (∼650 °C) related to the emplacement of plutonic rocks at shallow crustal levels (∼7–10 Km). An early stage high metamorphic grade foliation was overprinted by mylonitic deformation that progressively localized on low-metamorphic grade shear bands producing S-C mylonites during cooling of contact aureole. Localization of deformation on shear bands was driven by temperature decrease that triggered strain partitioning between ‘hard’ high grade relics and ‘soft’ shear bands. Softening of shear bands occurred likely due to fluid influx and retrograde growth of fine-grained phyllosilicates. The interconnection of anastomosing shear bands and passive rotation of the relic high grade foliation caused widening of the shear bands producing mylonites with a composite mylonitic foliation and C′ shear bands. An estimate of the vorticity number Wk of the flow of ∼0.3–0.5 was obtained from the orientation of C′ shear bands measured at the meso- and thin sectionscale. Close to the brittle-ductile transition, the growth of soft phyllosilicates allowed C′ shear bands to act as precursory structures to brittle deformation localized into an array of low-angle faults and shear fractures.
    Description: Published
    Description: 100-114
    Description: 1T. Struttura della Terra
    Description: JCR Journal
    Keywords: Brittle-ductile transition ; Mylonite Shear zone ; Shear band Faulting ; Strain localization ; Structural geology, brittle ductile transition
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Publication Date: 2022-06-09
    Description: To obtain a 3-D crustal density and shear-wave velocity structure beneath the Po plain we exploit seismic records gathered from 2006 to 2014 and Bouguer gravity data assembled for the last estimation of the Italian Geoid. 2-D maps for both Love and Rayleigh fundamental mode at periods between 4 and 20 s are obtained applying a tomographic inversion. The defined local dispersion curves are then jointly inverted using a linearized scheme to obtain a 3-D isotropic shear-wave velocity model across the Po plain region. The model, transformed into density through a priori velocity-density relationships, is then the input of the Sequential Integrated Inversion algorithm, which enables us to recover a new 3-D density-shear wave velocity coupling and inferences on the lithology and tectonics. Low and fast S-wave velocities are highlighted for the shallow Pliocene–Quaternary sediments along the foredeep, in front of the Northern Apennines, and for the presence of limestone units in the upper crust, respectively. Whereas sediment trends seem to be consistent with the results obtained, the Mesozoic carbonates, which are inherently characterized by high variability, are less resolved. A major result is the recovery of a high speed (3.3 km/s) - density (2.2 kg/m3) structure in the upper crust (6–10 km) localized beneath the arcuate Po plain thrust front expanding from the external margin of the Ferrara arc toward the Alps and the Adriatic Sea. At the boundaries of this brittle body, we locate earthquakes of the Emilia 2012 seismic sequence and the historical seismicity. Mapping lateral discontinuities in density and shear wave velocity could provide insights in defining strengthening and weakening zones, and in focusing on transition zones often prone to earthquakes.
    Description: Published
    Description: 262-279
    Description: 2TR. Ricostruzione e modellazione della struttura crostale
    Description: JCR Journal
    Keywords: Po plain ; 3D crustal model ; Surface waves ; Bouguer gravity anomalies
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3YOUMARES 8--Oceans Across Boundaries: Learning from each other, Springer, ISBN: 978-3-319-93284-2
    Publication Date: 2022-07-18
    Description: The Earth’s climate is changing and the poles are particularly sensitive to the global warming, with most evident implications over the Arctic. While summer sea ice reduced significantly compared to the previous decades, and the atmospheric warming is amplified over the Arctic, changes in the ocean are less obvious due to its higher inertia. Still, impacts of the changing climate on high-latitude and polar oceans are already observable and expected to further increase. The northern seas are essential regions for the maintenance of the Atlantic Meridional Overturning Circulation, which in turn is a key aspect of the maritime climate. Alterations in heat and freshwater/salinity content in the Arctic Ocean and adjacent seas impact and are closely linked to buoyancy flux distributions, which control the vertical and horizontal motion of water masses, thus impacting the climate system on a longer time scale. In this context, we set our focus on the Arctic Ocean and Atlantic subarctic seas, review some of the contemporary knowledge and speculations on the complex coupling between atmosphere, sea ice, and ocean, and describe the important elements of its physical oceanography. This assessment is an attempt to raise awareness that investigating the pathways and timescales of oceanic responses and contributions is fundamental to better understand the current climate change.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Publication Date: 2022-05-26
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marine Geology 404 (2018): 1-14, doi:10.1016/j.margeo.2018.06.016.
    Description: Recent major storms have piqued interest in understanding the responses of estuarine hydrodynamics and sediment transport to these events. To that end, flow velocity, wave characteristics, and suspended-sediment concentration (SSC) were measured for 11 months at eight locations in Chincoteague Bay, MD/VA, USA, a shallow back-barrier estuary. Daily breezes and episodic storms generated sediment-resuspending waves and modified the flow velocity at all sites, which occupied channel, shoal, and sheltered-bay environments with different bed-sediment characteristics. Despite comparable SSC during calm periods, SSC at the channel locations was considerably greater than at the shoal sites during windy periods because of relatively more erodible bed sediment in the channels. Sediment fluxes were strongly wind modulated: within the bay's main channel, depth-integrated unit-width sediment flux increased nonlinearly with increasing wind speed. When averaged over all sites, about 35% of the flux occurred during windy periods (wind speed greater than 6 m s−1), which represented just 15% of the deployment time. At channel sites, the net water and sediment fluxes were opposite to the direction of the wind forcing, while at shoal sites, the fluxes generally were aligned with the wind, implying complex channel–shoal dynamics. Yearly sediment fluxes exceed previous estimates of sediment delivery to the entirety of Chincoteague Bay. These observations illustrate the dynamic sedimentary processes occurring within microtidal back-barrier lagoons and highlight the importance of storm events in the hydrodynamics and overall sediment budgets of these systems.
    Description: his study was part of the Estuarine Physical Response to Storms project (GS2-2D), supported by the Department of the Interior Hurricane Sandy Recovery program.
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Publication Date: 2022-05-26
    Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Aquatic Sciences 80 (2018): 44, doi:10.1007/s00027-018-0594-z.
    Description: Complex natural systems are affected by multiple anthropogenic stressors, and therefore indirect effects within food webs are increasingly investigated. In this context, dead organic matter (OM) or detritus provides a food source sustaining detrital food webs that recycle the retained energy through microbial decomposition and invertebrate consumption. In aquatic environments, poorly water-soluble contaminants, including nanoparticles (NPs), quickly adsorb onto OM potentially modifying OM-associated microbial communities. Since invertebrates often depend on microbial conditioning to enhance OM quality, adverse effects on OM-associated microbial communities could potentially affect invertebrate performances. Therefore, this study assessed the effect of environmentally relevant concentrations of the model emerging contaminant, silver nanoparticles (AgNPs), on OM-associated microorganisms and subsequent indirect effects on growth of the invertebrate Asellus aquaticus. At low concentrations (0.8 ug/L), AgNPs inhibited activity and altered metabolic diversity of the OM-associated microbial community. This was observed to coincide with a negative effect on the growth of A. aquaticus due to antimicrobial properties, as a decreased growth was observed when offered AgNP-contaminated OM. When A. aquaticus were offered sterile OM in the absence of AgNPs, invertebrate growth was observed to be strongly retarded, illustrating the importance of microorganisms in the diet of this aquatic invertebrate. This outcome thus hints that environmentally relevant concentrations of AgNPs can indirectly affect the growth of aquatic invertebrates by affecting OM-associated microbial communities, and hence that microorganisms are an essential link in understanding bottom-up directed effects of chemical stressors in food webs.
    Description: The Chinese Scholarship Council (CSC) is gratefully acknowledged for its financial support to Yujia Zhai [201506510003]. Martina G. Vijver is funded by NWO-VIDI [project number 864.13.010].
    Keywords: Asellus aquaticus ; Food web ; Freshwater biofilms ; Decomposition and consumption ; Silver nanoparticles ; Ecosystem functioning
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Publication Date: 2022-05-26
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marine Geology 395 (2018): 301-319, doi:10.1016/j.margeo.2017.10.014.
    Description: A high-resolution multibeam echosounder (MBES) dataset covering over 279,000 km2 was acquired in the southeastern Indian Ocean to assist the search for Malaysia Airlines Flight 370 (MH370) that disappeared on 8 March 2014. The data provided an essential geospatial framework for the search and is the first large-scale coverage of MBES data in this region. Here we report on geomorphic analyses of the new MBES data, including a comparison with the Global Seafloor Geomorphic Features Map (GSFM) that is based on coarser resolution satellite altimetry data, and the insights the new data provide into geological processes that have formed and are currently shaping this remote deepsea area. Our comparison between the new MBES bathymetric model and the latest global topographic/bathymetric model (SRTM15_plus) reveals that 62% of the satellite-derived data points for the study area are comparable with MBES measurements within the estimated vertical uncertainty of the SRTM15_plus model (± 100 m). However, 〉 38% of the SRTM15_plus depth estimates disagree with the MBES data by 〉 100 m, in places by up to 1900 m. The new MBES data show that abyssal plains and basins in the study area are significantly more rugged than their representation in the GSFM, with a 20% increase in the extent of hills and mountains. The new model also reveals four times more seamounts than presented in the GSFM, suggesting more of these features than previously estimated for the broader region. This is important considering the ecological significance of high-relief structures on the seabed, such as hosting high levels of biodiversity. Analyses of the new data also enabled sea knolls, fans, valleys, canyons, troughs, and holes to be identified, doubling the number of discrete features mapped. Importantly, mapping the study area using MBES data improves our understanding of the geological evolution of the region and reveals a range of modern sedimentary processes. For example, a large series of ridges extending over approximately 20% of the mapped area, in places capped by sea knolls, highlight the preserved seafloor spreading fabric and provide valuable insights into Southeast Indian Ridge seafloor spreading processes, especially volcanism. Rifting is also recorded along the Broken Ridge – Diamantina Escarpment, with rift blocks and well-bedded sedimentary bedrock outcrops discernible down to 2400 m water depth. Modern ocean floor sedimentary processes are documented by sediment mass transport features, especially along the northern margin of Broken Ridge, and in pockmarks (the finest-scale features mapped), which are numerous south of Diamantina Trench and appear to record gas and/or fluid discharge from underlying marine sediments. The new MBES data highlight the complexity of the search area and serve to demonstrate how little we know about the vast areas of the ocean that have not been mapped with MBES. The availability of high-resolution and accurate maps of the ocean floor can clearly provide new insights into the Earth's geological evolution, modern ocean floor processes, and the location of sites that are likely to have relatively high biodiversity.
    Keywords: Indian Ocean ; Multibeam echosounder ; Geomorphology ; Processes ; Deepsea ; Seamount
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Publication Date: 2022-05-26
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ecological Modelling 368 (2018): 357-376, doi:10.1016/j.ecolmodel.2017.12.010.
    Description: Despite diel and seasonal vertical migrations (DVM and SVM) of high-latitude zooplankton have been studied since the late-19th century, questions still remain about the influence of environmental seasonality on vertical migration, and the combined influence of DVM and SVM on zooplankton fitness. Toward addressing these, we developed a model for simulating DVM and SVM of high-latitude herbivorous copepods in high spatio-temporal resolution. In the model, a unique timing and amplitude of DVM and SVM and its ontogenetic trajectory were defined as a vertical strategy. Growth, survival and reproductive performances of numerous vertical strategies hardwired to copepods spawned in different times of the year were assessed by a fitness estimate, which was heuristically maximized by a Genetic Algorithm to derive the optimal vertical strategy for a given model environment. The modelled food concentration, temperature and visual predation risk had a significant influence on the observed vertical strategies. Under low visual predation risk, DVM was less pronounced, and SVM and reproduction occurred earlier in the season, where capital breeding played a significant role. Reproduction was delayed by higher visual predation risk, and copepods that spawned later in the season used the higher food concentrations and temperatures to attain higher growth, which was efficiently traded off for survival through DVM. Consequently, the timing of SVM did not change much from that predicted under lower visual predation risk, but the body and reserve sizes of overwintering stages and the importance of capital breeding diminished. Altogether, these findings emphasize the significance of DVM in environments with elevated visual predation risk and shows its contrasting influence on the phenology of reproduction and SVM, and moreover highlights the importance of conducting field and modeling work to study these migratory strategies in concert.
    Description: This project was funded by VISTA (project no. 6165), a basic research program in collaboration between The Norwegian Academy of Science and Letters and Statoil. ØV received funding from the Fulbright Arctic Initiative.
    Keywords: Vertical migration ; Seasonality ; Phenology ; Optimization model ; Genetic algorithm ; Habitat choice
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Publication Date: 2022-05-26
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Climate Dynamics 50 (2018): 1291–1305, doi:10.1007/s00382-017-3685-y.
    Description: The role of the oceanic water cycle in the record-breaking 2015 warm-season precipitation in the US is analyzed. The extreme precipitation started in the Southern US in the spring and propagated northward to the Midwest and the Great Lakes in the summer of 2015. This seasonal evolution of precipitation anomalies represents a typical mode of variability of US warm-season precipitation. Analysis of the atmospheric moisture flux suggests that such a rainfall mode is associated with moisture export from the subtropical North Atlantic. In the spring, excessive precipitation in the Southern US is attributable to increased moisture flux from the northwestern portion of the subtropical North Atlantic. The North Atlantic moisture flux interacts with local soil moisture which enables the US Midwest to draw more moisture from the Gulf of Mexico in the summer. Further analysis shows that the relationship between the rainfall mode and the North Atlantic water cycle has become more significant in recent decades, indicating an increased likelihood of extremes like the 2015 case. Indeed, two record-high warm-season precipitation events, the 1993 and 2008 cases, both occurred in the more recent decades of the 66 year analysis period. The export of water from the North Atlantic leaves a marked surface salinity signature. The salinity signature appeared in the spring preceding all three extreme precipitation events analyzed in this study, i.e. a saltier-than-normal subtropical North Atlantic in spring followed by extreme Midwest precipitation in summer. Compared to the various sea surface temperature anomaly patterns among the 1993, 2008, and 2015 cases, the spatial distribution of salinity anomalies was much more consistent during these extreme flood years. Thus, our study suggests that preseason salinity patterns can be used for improved seasonal prediction of extreme precipitation in the Midwest.
    Description: LL is supported by the Postdoctoral Scholar Program at WHOI, with funding provided by the Oceans and Climate Change Institute. RWS is supported by NASA Grants NNX12AF59G and NNX14AH38G, and NSF Grant OCE-1129646. CCU is supported by NSF Grant AGS-1355339.
    Keywords: US extreme precipitation ; Oceanic water cycle ; Ocean-to-land moisture transport ; Sea surface salinity
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Publication Date: 2022-05-26
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marine Pollution Bulletin 126 (2018): 1-18, doi:10.1016/j.marpolbul.2017.10.034.
    Description: Loud sound emitted during offshore industrial activities can impact marine mammals. Regulations typically prescribe marine mammal monitoring before and/or during these activities to implement mitigation measures that minimise potential acoustic impacts. Using seismic surveys under low visibility conditions as a case study, we review which monitoring methods are suitable and compare their relative strengths and weaknesses. Passive acoustic monitoring has been implemented as either a complementary or alternative method to visual monitoring in low visibility conditions. Other methods such as RADAR, active sonar and thermal infrared have also been tested, but are rarely recommended by regulatory bodies. The efficiency of the monitoring method(s) will depend on the animal behaviour and environmental conditions, however, using a combination of complementary systems generally improves the overall detection performance. We recommend that the performance of monitoring systems, over a range of conditions, is explored in a modelling framework for a variety of species.
    Description: This work was supported by the Joint Industry Programme on E&P Sound and Marine Life - Phase III. TAM was partially supported by CEAUL (funded by FCT - Fundação para a Ciência e a Tecnologia, Portugal, through the project UID/MAT/00006/2013).
    Keywords: Marine mammals ; Monitoring methods ; Underwater noise ; Seismic survey ; Detection performance ; Low visibility
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Publication Date: 2022-05-26
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ocean Modelling 121 (2018): 49-75, doi:10.1016/j.ocemod.2017.11.008.
    Description: Lagrangian analysis is a powerful way to analyse the output of ocean circulation models and other ocean velocity data such as from altimetry. In the Lagrangian approach, large sets of virtual particles are integrated within the three-dimensional, time-evolving velocity fields. Over several decades, a variety of tools and methods for this purpose have emerged. Here, we review the state of the art in the field of Lagrangian analysis of ocean velocity data, starting from a fundamental kinematic framework and with a focus on large-scale open ocean applications. Beyond the use of explicit velocity fields, we consider the influence of unresolved physics and dynamics on particle trajectories. We comprehensively list and discuss the tools currently available for tracking virtual particles. We then showcase some of the innovative applications of trajectory data, and conclude with some open questions and an outlook. The overall goal of this review paper is to reconcile some of the different techniques and methods in Lagrangian ocean analysis, while recognising the rich diversity of codes that have and continue to emerge, and the challenges of the coming age of petascale computing.
    Description: EvS has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (grant agreement No 715386). This research for PJW was supported as part of the Energy Exascale Earth System Model (E3SM) project, funded by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research. Funding for HFD was provided by Grant No. DE-SC0012457 from the US Department of Energy. PB acknowledges support for this work from NERC grant NE/R011567/1. SFG is supported by NERC National Capability funding through the Extended Ellett Line Programme.
    Keywords: Ocean circulation ; Lagrangian analysis ; Connectivity ; Particle tracking ; Future modelling
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Publication Date: 2022-05-26
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Progress in Earth and Planetary Science 4 (2017): 41, doi:10.1186/s40645-017-0154-5.
    Description: During the past several decades, the Earth system has changed significantly, especially across Northern Eurasia. Changes in the socio-economic conditions of the larger countries in the region have also resulted in a variety of regional environmental changes that can have global consequences. The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to better prepare societies for future developments. A key principle of NEFI is that these developments must now be secured through science-based strategies co-designed with regional decision-makers to lead their societies to prosperity in the face of environmental and institutional challenges. NEESPI scientific research, data, and models have created a solid knowledge base to support the NEFI program. This paper presents the NEFI research vision consensus based on that knowledge. It provides the reader with samples of recent accomplishments in regional studies and formulates new NEFI science questions. To address these questions, nine research foci are identified and their selections are briefly justified. These foci include warming of the Arctic; changing frequency, pattern, and intensity of extreme and inclement environmental conditions; retreat of the cryosphere; changes in terrestrial water cycles; changes in the biosphere; pressures on land use; changes in infrastructure; societal actions in response to environmental change; and quantification of Northern Eurasia’s role in the global Earth system. Powerful feedbacks between the Earth and human systems in Northern Eurasia (e.g., mega-fires, droughts, depletion of the cryosphere essential for water supply, retreat of sea ice) result from past and current human activities (e.g., large-scale water withdrawals, land use, and governance change) and potentially restrict or provide new opportunities for future human activities. Therefore, we propose that integrated assessment models are needed as the final stage of global change assessment. The overarching goal of this NEFI modeling effort will enable evaluation of economic decisions in response to changing environmental conditions and justification of mitigation and adaptation efforts.
    Description: Support for most of the US authors and contributors of this paper as well as the multiannual support for the office of the NEESPI Project Scientist was provided by the NASA Land Cover and Land Use Change (LCLUC) Program, in particular, by grants NNX13AC66G, NNX11AB77G, NNX13AN58G, NNX15AD10G, NAG5–11084, 08–LCLUC08–2–0003, NNX14AD88G, NNX08AW51G, NNX12AD34G, NNX14AD91G, and NNX15AP81G. The research carried out at the Jet Propulsion Laboratory, California Institute of Technology, was also supported by the NASA LCLUC Program. Support of NASA grants 08–TE08–029 and NNH09ZDA001N–IDS for AS and NT are acknowledged. Research of MS is supported by Newton-al-Farabi Fund (grant 172722855). Grant 14.B25.31.0026 of the Ministry of Education and Science of the Russian Federation provided support to PG, SG, NT, AS, OB, BP, and IP for their work conducted at the P.P. Shirshov Institute of Oceanology. The Project “ARCTIC-ERA: ARCTIC climate change and its impact on Environment, infrastructures, and Resource Availability” sponsored by: ANR (France), RFBR (Russia), and the US NSF (grants 1717770 and 1558389) in response to Belmont Forum Collaborative Research Action on Arctic Observing and Research for Sustainability provided support for OZ, SG, BP, PG, and NS. A part of the paper is based on the research carried out with the financial support of the Russian Foundation for Basic Research (Project No. 15–06–08163 “Assessment and forecast of the socioeconomic and environmental implications of the climate change in the Arctic region”). Support for AP is provided by the Russian Government Program of Competitive Growth of Kazan Federal University (OpenLab Initiative). Support for JA is provided by grant NPUILO1417 of the Ministry of Education, Youth and Sports of Czechia.
    Keywords: Environmental changes ; Northern Eurasia ; Ecosystems dynamics ; Terrestrial water cycle ; Cryosphere retreat ; Extreme and inclement environmental conditions ; Sustainable development ; Land cover and land use change ; Integrated assessment models for decision-makers
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Publication Date: 2022-05-26
    Description: This paper is not subject to U.S. copyright. The definitive version was published in Geomorphology 300 (2018): 189-202, doi:10.1016/j.geomorph.2017.08.004.
    Description: Hurricane Sandy at Fire Island, New York presented unique challenges in the quantification of storm impacts using traditional metrics of coastal change, wherein measured changes (shoreline, dune crest, and volume change) did not fully reflect the substantial changes in sediment redistribution following the storm. We used a time series of beach profile data at Fire Island, New York to define a new contour-based morphologic change metric, the Beach Change Envelope (BCE). The BCE quantifies changes to the upper portion of the beach likely to sustain measurable impacts from storm waves and capture a variety of storm and post-storm beach states. We evaluated the ability of the BCE to characterize cycles of beach change by relating it to a conceptual beach recovery regime, and demonstrated that BCE width and BCE height from the profile time series correlate well with established stages of recovery. We also investigated additional applications of this metric to capture impacts from storms and human modification by applying it to several post-storm historical datasets in which impacts varied considerably; Nor'Ida (2009), Hurricane Irene (2011), Hurricane Sandy (2012), and a 2009 community replenishment. In each case, the BCE captured distinctive upper beach morphologic change characteristic of these different beach building and erosional events. Analysis of the beach state at multiple profile locations showed spatial trends in recovery consistent with recent morphologic island evolution, which other studies have linked with sediment availability and the geologic framework. Ultimately we demonstrate a new way of more effectively characterizing beach response and recovery cycles to evaluate change along sandy coasts.
    Description: This work was supported by the 2013 Disaster Relief Appropriations Act, Department of Interior Hurricane Sandy Supplemental Project GS2-2B.
    Keywords: Barrier Island ; Coastal geomorphology ; Storm response ; Beach recovery
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Publication Date: 2022-05-26
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marine Micropaleontology 138 (2018): 12-32, doi:10.1016/j.marmicro.2017.10.005.
    Description: We report systematic transmission electron microscope (TEM) observations of the cellular ultrastructure of selected, small rotalid benthic foraminifera. Nine species from different environments (intertidal mudflat, fjord, and basin) were investigated: Ammonia sp., Elphidium oceanense, Haynesina germanica, Bulimina marginata, Globobulimina sp., Nonionellina labradorica, Nonionella sp., Stainforthia fusiformis and Buliminella tenuata. All the observed specimens were fixed just after collection from their natural habitats allowing description of intact and healthy cells. Foraminiferal organelles can be divided into two broad categories: (1) organelles that are present in all eukaryotes, such as the nuclei, mitochondria, endoplasmic reticulum, Golgi apparatus, and peroxisomes; and (2) organelles observed in all foraminifera but not common in all eukaryotic cells, generally with unknown function, such as fibrillar vesicles or electron-opaque bodies. Although the organelles of the first category were observed in all the observed species, their appearance varies. For example, subcellular compartments linked to feeding and metabolism exhibited different sizes and shapes between species, likely due to differences in their diet and/or trophic mechanisms. The organelles of the second category are common in all foraminiferal species investigated and, according to the literature, are frequently present in the cytoplasm of many different species, both benthic and planktonic. This study, thus, provides a detailed overview of the major ultrastructural components in benthic foraminiferal cells from a variety of marine environments, and also highlights the need for further research to better understand the function and role of the various organelles in these fascinating organisms.
    Description: This work was supported by the Swiss National Science Foundation (grant no. 200021_149333), The Investment in Science Fund at WHOI and the French national program EC2CO-LEFE (project ForChlo). TJ was funded by the “FRESCO” project, a project supported by the Region Pays de Loire and the University of Angers.
    Keywords: Protist ; Organelles ; TEM ; Cytology ; Mudflat ; Gullmar Fjord
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Publication Date: 2022-05-26
    Description: © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Science of The Total Environment 621 (2018): 1185-1198, doi:10.1016/j.scitotenv.2017.10.109.
    Description: We made an assessment of the levels of radionuclides in the ocean waters, seafloor and groundwater at Bikini and Enewetak Atolls where the US conducted nuclear weapons tests in the 1940's and 50's. This included the first estimates of submarine groundwater discharge (SGD) derived from radium isotopes that can be used here to calculate radionuclide fluxes in to the lagoon waters. While there is significant variability between sites and sample types, levels of plutonium (239,240Pu) remain several orders of magnitude higher in lagoon seawater and sediments than what is found in rest of the world's oceans. In contrast, levels of cesium-137 (137Cs) while relatively elevated in brackish groundwater are only slightly higher in the lagoon water relative to North Pacific surface waters. Of special interest was the Runit dome, a nuclear waste repository created in the 1970's within the Enewetak Atoll. Low seawater ratios of 240Pu/239Pu suggest that this area is the source of about half of the Pu in the Enewetak lagoon water column, yet radium isotopes suggest that SGD from below the dome is not a significant Pu source. SGD fluxes of Pu and Cs at Bikini were also relatively low. Thus radioactivity associated with seafloor sediments remains the largest source and long term repository for radioactive contamination. Overall, Bikini and Enewetak Atolls are an ongoing source of Pu and Cs to the North Pacific, but at annual rates that are orders of magnitude smaller than delivered via close-in fallout to the same area.
    Description: Finally, none of this would have been possible without the generous financial support from the Dalio Explore Fund (WHOI #25531513) for the vessel and our post cruise analyses that together resulted in this unique and successful research program.
    Keywords: Marshall Islands ; Runit dome ; Plutonium ; Cesium ; Radium ; Nuclear weapons tests
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Building bridges at the science-stakeholder interface - Towards knowledge exchange in Earth System Science, SpringerBriefs in Earth System Sciences, Cham, Switzerland, Springer, pp. 69-72, ISBN: 978-3-319-75918-0
    Publication Date: 2023-06-21
    Description: The new knowledge and data portal ‘meereisportal.de’ is a contribution to the cross-linking of scientifically qualified information on climate change. It focuses deliberately on the theme ‘sea ice in both Polar Regions’. With the establishment of ‘meereisportal.de’, science adapts to changing societal demands and embarks on new ways of communication between science and society.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3YOUMARES 8 – Oceans Across Boundaries: Learning from each other, Cham, Springer, pp. 109-124, ISBN: 978-3-319-93283-5
    Publication Date: 2023-06-21
    Description: From the depths of the oceans to the shallow estuaries and wetlands of our coasts, organisms of the marine environment are teeming with unique adaptations to cope with a multitude of varying environmental conditions. With millions of years and a vast volume of water to call their home, they have become quite adept at developing specialized and unique techniques for survival and – given increasing human mediated transport – biological invasions. A growing world human population and a global economy drives the transportation of goods across the oceans and with them invasive species via ballast water and attached to ship hulls. In any given 24-hour period, there are about 10,000 species being transported across different biogeographic regions. If any of them manage to take hold and establish a range in an exotic habitat, the implications for local ecosystems can be costly. This review on marine invasions highlights trends among successful non-indigenous species (NIS), from vectors of transport to ecological and physiological plasticity. Apart from summarizing patterns of successful invasions, it discusses the implications of how successfully established NIS impact the local environment, economy and human health. Finally, it looks to the future and discusses what questions need to be addressed and what models can tell us about what the outlook on future marine invasions is.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Building bridges at the science-stakeholder interface - Towards knowledge exchange in earth system science, SpringerBriefs in Earth System Sciences, Cham, Switzerland, Springer, 132 p., pp. 19-29, ISBN: 987-3-319-75918-0
    Publication Date: 2023-06-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3YOUMARES 8 – Oceans Across Boundaries: Learning from each other, YOUMARES 8 – Oceans Across Boundaries: Learning from each other, Phytoplankton Responses to Marine Climate Change – An Introduction, Springer, pp. 55-71, ISBN: 978-3-319-93284-2
    Publication Date: 2023-06-21
    Description: Phytoplankton are one of the key players in the ocean and contribute approximately 50% to global primary production. They serve as the basis for marine food webs, drive chemical composition of the global atmosphere and thereby climate. Seasonal environmental changes and nutrient availability naturally influence phytoplankton species composition. Since the industrial era, anthropogenic climatic influences have increased noticeably – also within the ocean. Our changing climate, however, affects the composition of phytoplankton species composition on a long-term basis and requires the organisms to adapt to this changing environment, influencing micronutrient bioavailability and other biogeochemical parameters. At the same time, phytoplankton themselves can influence the climate with their responses to environmental changes. Due to its key role, phytoplankton has been of interest in marine sciences for quite some time and there are several methodical approaches implemented in oceanographic sciences. There are ongoing attempts to improve predictions and to close gaps in the understanding of this sensitive ecological system and its responses.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...