ALBERT

Description: To provide a contribution to the Thematic Strategy for Soil Protection, here we present the results of a study focused on the potentially toxic elements (PTE) content in agricultural soils’ representative for the Mediterranean region. To reach this aim, samples of 22 Italian (NE Peloritani Mountains, Sicily) and 18 Turkish (Amik Plain, Hatay) soils were collected and analyzed to evaluate their PTE content. The Italian and Turkish sites have been selected because they represent very important cultivation zones. In Amik Plain (Turkey), the dominant crops consist of cotton, wheat, corn and olives, whereas in NE Peloritani Mountains, Sicily (Italy), an appreciate citrus variety, known as the “Interdonato lemon”, guaranteed by Protected Geographical Indication label, is produced. The collected results include: (1) the assessment of PTE levels in soils; (2) the identifcation of the PTE sources; (3) the relationships between PTE contents and soil properties (pH, electrical conductivity, organic matter, CaCO3, and clay). Several multivariate statistical methods such as correlation matrix, cluster analysis and main component analysis were applied to individuate the anthropogenic vs natural origin of the PTE sources. The detected PTE levels are in decreasing order Mn〉Zn〉V〉Cr〉Cu〉Ni〉As〉Pb〉Co〉Sb〉Se〉Cd for the Italian soils, and Mn〉 Ni〉V〉Zn〉Cr〉Cu〉Pb〉Co〉As〉Se〉Sb〉Cd for the Turkish soils. The overall obtained results allowed to defne: (a) a main lithogenic source for PTE detected in the Italian soils, except for Zn which origin is also associated to anthropogenic input; (b) a lithogenic origin for all of the PTE detected for the Turkish soils, with an associate anthropogenic contribution for Cr, Ni, V, Cu and V. The results obtained in this work enhance the knowledge in the individuation of PTE pollution sources in agricultural soils of the European Mediterranean region.

Description: Published

Description: 499

Description: 6A. Geochimica per l'ambiente e geologia medica

Description: JCR Journal

Description: Coastal dynamics are the result of several processes controlling the balance between sediment input and output over time. The beach system is not always able to maintain a neutral coastal balance due to natural and anthropogenic causes. We present an integrated marine geology, geomorphological and sea-level rise analysis in the coastal sector between Torre delle Ciavole and Capo Calavà (North-Eastern Sicily, Italy).This sector is characterized by high uplift rates and frequent seismicity (mainly generated by the very active Vulcano-Tindari Fault System), promoting the development of mass-wasting processes in the coastal and offshore sectors. A main erosive feature observed in the area is the head of the Gioiosa Marea submarine canyon, located at some meters of depth, few hundred meters far the coastline. The main morphological features of the canyon were reconstructed through the analysis of high-resolution multibeam data, indicating that the canyon is active, as also testified by the comparison of time-lapse aerial photos. Due to this active setting, the study area is exposed to multiple geohazards, among which we deal with: (1) retrogressive instability at the head of the Gioiosa Marea submarine canyon, (2) coastal erosion favored by the downlope funnelling of littoral drift at the canyon head, (3) flooding scenario at 2100 using the IPCC (Intergovernmental Panel on Climate Change) and Rahmstorf sea-level projections. The consequences associated with these geohazards are amplified by the strong anthropization pressures occurring along in this sector. Our results provide key insights regarding the future scenarios of this coastal sector, revealing the effects of the retrogressive activity associated with the canyon head on the coastal strip. We also present the first management tool for the application of forecasting studies by local administrations.

Description: Published

Description: 2

Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare

Description: JCR Journal

Description: New geochemical and isotopic data on volcanic rocks spanning the period ~75–50 ka BP on Ischia volcano, Italy, shed light on the evolution of the magmatic system before and after the catastrophic, caldera-forming Monte Epomeo Green Tuff (MEGT) eruption. Volcanic ac tivity during this period was influenced by a large, composite and differentiating magmatic system, replenished several times with isotopically distinct magmas of deepprovenance. Chemical and isotopic variations highlight that the pre-MEGT eruptions were fed by trachytic/phonolitic magmas from an isotopically zoned reservoir that were poorly enriched in radiogenic Sr and became progressively less radiogenic with time. Just prior to the MEGT eruption, the magmatic system was recharged by an isotopically distinct magma, relatively more enriched in radiogenic Sr with respect to the previously erupted magmas. This second magma initially fed several SubPlinian explosive eruptions and later supplied the climactic, phonolitic-to-trachytic MEGT eruption(s). Isotopic data, together with erupted volume estimations obtained for MEGT eruption(s), indicate that 〉5–10 km3of this relatively enriched magma had accumulated in the Ischia plumbing system. Geochemical modelling indicates that it accumulated at shallow depths (4–6 km), over a period of ca. 20 ka. After the MEGT eruption, volcanic activity was fed by a new batch of less differentiated (trachyte-latite) magma that was slightly less enriched in radiogenic Sr. The geochemical and Sr–Nd-isotopic variations through time reflect the upward flux of isotopically distinct magma batches, variably contaminated byHercynian crust at 8–12 km depth. The deep-sourced latitic to trachytic magmas stalled at shallow depths (4–6 km depth), differentiated to phonolite through crystal fractionation and assimilation of a feldspar-rich mush, or ascended directly to the surface and erupted.

Description: Published

Description: 1035

Description: 2V. Struttura e sistema di alimentazione dei vulcani

Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici

Description: 4V. Processi pre-eruttivi

Description: 6A. Geochimica per l'ambiente e geologia medica

Description: JCR Journal

Description: During the past millennia, several eruptions have occurred within the La Fossa caldera on the island of Vulcano (Aeolian Islands, Italy), some being also described in historical documents dating back to Republican Roman times (first to second century BC). The absolute and relative timing of such activity, however, has remained poorly defined and controversial, due to contrasting ages provided by radiometric and unconventional palaeomagnetic methods. Here, we present a detailed recon- struction of the eruptive history focused on the ninth to fifteenth century AD period that occurred at both La Fossa cone and Vulcanello. This integrated approach involves tephrostratigraphy, standard palaeomagnetic methodology and radiocarbon dating. The new dataset confirms that the lavas exposed above sea level at Vulcanello were erupted between the tenth and eleventh century AD, and not between the first and second century BC as previously suggested. In this same time interval, La Fossa cone was characterized by long-lasting, shoshonitic, explosive activity followed by a discrete, sustained, rhyolitic explosive eruption. Between AD 1050 and 1300, activity was focused only on La Fossa cone, with alternating explosive and effusive eruptions that emplaced four rhyolitic and trachytic lava flows, resulting in significant growth of the cone. After the violent, phreatic event of the Breccia di Commenda (thirteenth century), the eruption continued with a substantial, long- lasting emission of fine ash until activity ceased. Magmatic explosive activity resumed at La Fossa cone at the beginning of the fifteenth century marking the onset of the Gran Cratere cycle. This phase lasted until the mid-sixteenth century and produced at least seven explosive eruptions of intermediate magma composition and a couple of lateral explosions (Forgia Vecchia I and II). During this time interval, a third cinder cone was emplaced at Vulcanello, and the activity produced the lava flows of Punta del Roveto and Valle dei Mostri. From the seventeenth to twentieth centuries, volcanic activity was concentrated at La Fossa cone, where it ended in 1890. This work confirms that Vulcanello island formed in Medieval times between the tenth and eleventh centuries. Moreover, between the tenth and mid-sixteenth centuries, La Fossa caldera was the site of at least 19 eruptions with an average eruption rate of one event every 34 years. This rate makes volcanic hazard at Vulcano higher than that suggested to date.

Description: Published

Description: 12

Description: 1A. Geomagnetismo e Paleomagnetismo

Description: JCR Journal

Description: This book outlines the current development of geoethical thinking, proposing to the general public reflections and categories useful for understanding the ethical, cultural, and societal dimensions of anthropogenic global changes. Geoethics identifies and orients responsible behaviors and actions in the management of natural processes, redefining the human interaction with the Earth system based on a critical, scientifically grounded, and pragmatic approach. Solid scientific knowledge and a philosophical reference framework are crucial to face the current ecological disruption. The scientific perspective must be structured to help different human contexts while respecting social and cultural diversity. It is impossible to respond to global problems with disconnected local actions, which cannot be proposed as standard and effective operational models. Geoethics tries to overcome this fragmentation, presenting Earth sciences as the foundation of responsible human action toward the planet. Geoethics is conceived as a rational and multidisciplinary language that can bind and concretely support the international community, engaged in resolving global environmental imbalances and complex challenges, which have no national, cultural, or religious boundaries that require shared governance. Geoethics is proposed as a new reading key to rethinking the Earth as a system of complex relationships, in which the human being is an integral part of natural interactions.

Description: Published

Description: 1TM. Formazione

Description: 2TM. Divulgazione Scientifica

Description: 3TM. Comunicazione

Description: The availability of computer tools able to describe the behavior of pyroclastic density currents (PDCs) with uncertainty quantification is of primary importance for the assessment of volcanic hazard. A common strategy to assess the intrinsic variability of these phenomena is based on the analysis of large sets of numerical simulations with variable input parameters. The use of models fast enough to allow for a large number of simulations, such as the so-called kinetic energy models, is thus advantageous. Due to the sensitivity of kinetic energy models to poorly constrained input parameters, the definition of their variation ranges is a critical step in the construction of hazard maps and a numerical calibration becomes necessary. We present a set of reproducible and structured calibration procedures of numerical models based either on a reference deposit or on the distribution of runout distance or inundation area of documented PDCs. In the first case, various metrics can be adopted to compare the model results with the reference PDC deposit (root mean square distance, Hausdorff distance, and Jaccard index), facilitating the development of scenario-based hazard assessments. Calibrations based on the distribution of runout distance or inundation area allow the construction of probabilistic hazard maps that are not conditioned on the occurrence of a specific scenario, but rather reflect the variability of the documented PDCs during the time window considered. Importantly, our calibration strategies allow one to set the input parameters considering their potential statistical dependence. These procedures have been implemented on the user-friendly versions of two kinetic energy models: ECMapProb 2.0 and BoxMapProb 2.0, whose functionalities are presented for the first time in this paper. The different calibration strategies and the functionalities of the two programs are illustrated by considering three case studies: El Misti (Peru), Merapi (Indonesia), and Campi Flegrei (Italy).

Description: Published

Description: 29

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: JCR Journal

Description: In this work, we assess ground shaking in the wider Zagreb area by computing simulated seismograms at regional distances. For the purposes of the simulations, we assemble the 3D velocity and density model and test its performance. First, we compare the low-frequency simulations obtained using deterministic method for both new 3D model and a simple 1D model. We then continue the performance test by computing the full broadband seismo- grams. To do that, we apply the hybrid technique in which the low frequency (f〈1 Hz) and high frequency (f=1–10 Hz) seismograms are obtained separately using deterministic and stochastic method, respectively, and then reconciled into a single time series. We apply this method to the MW=5.3 event and four smaller (3.0〈MW〈5.0) events that occurred in the studied region. We compare simulated data with the recorded seismograms and vali- date our results by calculating the goodness of fit score for peak ground velocity and shak- ing duration. Next, to improve the understanding of the strong ground motion in this area, we simulate seismic shaking scenarios for the 1880, MW = 6.2 earthquake. From computed low-frequency waveforms, we generate shakemaps and compare the ground-motion fea- tures of the two possible sources of this event, Kašina fault and North Medvednica fault. We conduct a preliminary study to determine which fault is a more probable source of the 1880 historic event by comparing the peak ground velocities and Arias intensity with the observed intensities.

Description: Croatian Science Foundation under the Project No. IP-2020-02-3960 European Commission, H2020 Excel- lence Science [ChEESE (Grant No. 823844)]

Description: Published

Description: 167–192

Description: 1T. Struttura della Terra

Description: 6T. Studi di pericolosità sismica e da maremoto

Description: JCR Journal

Description: Geomorphological investigations in Rome’s river valley are revealing the dynamism of the prehistoric landscape. It is becoming increasingly apparent that paleogeographic conditions that defined Rome in the historical era are the product of changes since the Bronze Age, which may be the result of local fault activity in addition to fluvial dynamism. Through a dedicated borehole chronostratigraphic study, integrated by 14C and archaeological dates, and paleomagnetic investigations, we offer here new evidence for fault displacement since ca. 4500 years/BP. We present the failure of the sedimentary fabric of a clay horizon caused by liquefaction processes commonly linked with seismic shaking, interpreting an (ca. 4 m) offset to signify the existence of a fault line located at the foot of the Capitoline Hill. In addition, we show evidence for another (ca. 1 m) offset affecting a stratigraphic horizon in the river channel, occurring along another hypothesized fault line crossing through the Tiber Valley. Movement along this fault may have contributed to a documented phase of fast overflooding dated to the sixth century BCE which eventually led to the birth of the Tiber Island. The most plausible scenario implies progressive deformation, with an average tectonic rate of 2 mm/year, along these inferred fault lines. This process was likely punctuated with moderate earthquakes, but no large event necessarily occurred. Together, the available evidence suggests that during the early centuries of sedentary habitation at the site of Rome, active fault lines contributed to significant changes to the Tiber River valley, capable of challenging lowland activities.

Description: Published

Description: 359–378

Description: 2T. Deformazione crostale attiva

Description: JCR Journal

Description: In November 2019, the fourth meeting on Volcano Observatory Best Practices workshop was held in Mexico City as a series of talks, discussions, and panels. Volcanologists from around the world offered suggestions for ways to optimize volcano-observatory crisis operations. By crisis, we mean unrest that may or may not lead to eruption, the eruption itself, or its aftermath, all of which require analysis and communications by the observatory. During a crisis, the priority of the observatory should be to acquire, process, analyze, and interpret data in a timely manner. A primary goal is to communicate effectively with the authorities in charge of civil protection. Crisis operations should rely upon exhaustive planning in the years prior to any actual unrest or eruptions. Ideally, nearly everything that observatories do during a crisis should be envisioned, prepared, and practiced prior to the actual event. Pre-existing agreements and exercises with academic and government collaborators will minimize confusion about roles and responsibilities. In the situation where planning is unfinished, observatories should prioritize close ties and communications with the land and civil-defense authorities near the most threatening volcanoes.

Description: Published

Description: 3

Description: 6SR VULCANI – Servizi e ricerca per la società

Description: N/A or not JCR

Description: The increased concentration of greenhouse gases in the atmosphere from human activities traps heat within the climate system and increases ocean heat content (OHC). Here, we provide the first analysis of recent OHC changes through 2021 from two international groups. The world ocean, in 2021, was the hottest ever recorded by humans, and the 2021 annual OHC value is even higher than last year’s record value by 14 ± 11 ZJ (1 zetta J = 1021 J) using the IAP/CAS dataset and by 16 ± 10 ZJ using NCEI/NOAA dataset. The long-term ocean warming is larger in the Atlantic and Southern Oceans than in other regions and is mainly attributed, via climate model simulations, to an increase in anthropogenic greenhouse gas concentrations. The year-to-year variation of OHC is primarily tied to the El Niño-Southern Oscillation (ENSO). In the seven maritime domains of the Indian, Tropical Atlantic, North Atlantic, Northwest Pacific, North Pacific, Southern oceans, and the Mediterranean Sea, robust warming is observed but with distinct inter-annual to decadal variability. Four out of seven domains showed record-high heat content in 2021. The anomalous global and regional ocean warming established in this study should be incorporated into climate risk assessments, adaptation, and mitigation.

Description: Published

Description: 373–385

Description: 4A. Oceanografia e clima

Description: JCR Journal

Description: Physics of earthquake source can be investigated by monitoring active faults from borehole observatory in reservoirs (Maxwell et al. 2010) or by interpretation of seismic waves at the earth’s surface (Shearer 2019). Indeed, most information on earthquake mechanics is retrieved from seismology (e.g., Lee et al. 2002). However, the low resolution of these indirect techniques (cm to km scale) yields limited information on the physical and chemical deformation mechanisms active during earthquake rupture nucleation and propagation (Kanamori and Anderson 1975). Experimental studies of frictional instabilities on fault gouge material or pre-existing surfaces (e.g., Brace and Byerlee 1966) may overcome those limitations (Scholz 1998; Marone 1998; Persson 2013). For instance, friction controls earthquake nucleation and propagation, the static and dynamic stress drops, the frictional heat generated during slip, and consequently the energy budget of earthquakes (Scholz 2019; Di Toro et al. 2011). All these processes can be investigated and monitored through laboratory experiments. In the last decades, rock friction properties have long been investigated using triaxial apparatuses in saw-cut configuration (e.g., Jaeger 1959; Byerlee 1967; Handin 1969), in which the fault is loaded at low velocities, typically orders of µm/s, and accumulates small displacements, typically few mm. In a seminal paper, Brace and Byerlee (1966) suggested that the stick–slip phenomenon observed in these rock friction experiments is analogous to natural earthquakes. Furthermore, to address the problem of earthquakes nucleation, biaxial apparatuses were developed and have long been used to study frictional properties of experimental faults under sub-seismic slip velocities in double-direct shear configuration (e.g., Dieterich 1972; Mair et al. 2002; Collettini et al. 2014; Giorgetti et al. 2015). The biaxial apparatus developed at USGS (USA) is amongst the first biaxial apparatuses used to investigate rock frictional properties (e.g., Dieterich 1972). Other pioneering biaxial apparatuses are the one in the Rock and Sediment Mechanics Laboratory at the Pennsylvania State University (USA) (e.g., Mair et al. 2002) and BRAVA (Brittle Rock deformAtion Versatile Apparatus) installed at INGV in Rome (Italy) (Collettini et al. 2014). Although the biaxial apparatuses developed in the past 50 years are characterized by different boundary conditions in terms of forces, pressures, temperatures and size of the samples, all of them take advantages from the double-direct shear configuration that allows good control of the normal and shear forces acting of the fault, accurate measurements of fault slip and dilation/compaction, and constant contact area. Friction studies conducted with triaxial and biaxial deformation apparatuses are characterized by sub-seismic slip velocities and a limited amount of slip, 〈 10–3 m/s and few cm, respectively (e.g., Jaeger 1959; Byerlee 1967,1978; Brace and Byerlee 1966; Handin 1969; Paterson and Wong 2005; Lockner and Beeler 2002; Mair et al. 2002; Savage and Marone 2007; Samuelson et al. 2009; Carpenter et al. 2016). These experiments showed that the apparent static friction coefficient μ (i.e., μ = τ/σneff, where τ is the shear stress and σneff the effective normal stress acting on the fault) is between 0.60 and 0.85 for most rocks (Byerlee’s rule; except for phyllosilicates-rich rocks [Byerlee 1978]), for normal stresses up to 2 GPa, and temperatures up to 780 K. The apparent friction can thus be expressed as a function of slip velocity and a state variable, and modelled with the empirical rate- and state-dependent friction law (Dieterich 1979; Ruina 1983). Additionally, at velocities typical of earthquake nucleation phase, the apparent friction varies only a few percents for small changes in slip velocity, determining if a fault is or not prone to nucleate earthquakes. Although Byerlee’s rule and the rate-and-state law have many applications in earthquake mechanics (inter-seismic and nucleation phase of earthquakes), these experiments were performed at slip velocities and displacements orders of magnitude smaller than those of earthquakes. Therefore, these experiments are unable to characterize the propagation phase of earthquakes. In the last 15 years, the multiplication of the rotary shear apparatus, designed to achieve slip velocities higher than 1 m/s and infinite displacement, overcome those limitations and produced unexpected results (Di Toro et al. 2010). A pioneering rotary shear apparatus capable of achieving seismic slip velocities up to 1.3 m/s were built and installed in Japan (Shimamoto 1994). Amongst others (see Di Toro et al. 2010 and references therein), a state-of-art rotary shear apparatus (SHIVA, Slow to High-Velocity Shear Apparatus) capable of deforming samples at slip rates up to 9 m/s has been installed at INGV in Rome (Italy) (Di Toro et al. 2010). Studies performed with these rotary shear apparatuses have shown a significant decrease in fault strength with increasing slip and slip velocity. They also reveal various dynamic fault‐weakening mechanisms (frictional melting, thermal pressurization, silica gel, elastohydrodynamic lubrication) that are likely active during earthquakes, including mechanisms that were unknown before conducting these experiments. Though this new frontier is promising, key aspects of earthquake mechanics laboratory investigation, like being able to conduct high slip velocity experiments on rocks under elevated pore fluid pressure and temperatures characteristic of natural and induced earthquakes, remain beyond current experimental capabilities. Furthermore, studying links between pore‐fluid pressure, permeability, and frictional properties remains a challenge. To date, very few high-velocity friction experiments have been performed in presence of pore fluid pressure (Tanikawa 2012a, b, 2014; Violay et al. 2014, 2015, 2019; Cornelio et al. 2019a, b). In this paper, we present a new state-of-art apparatus combining the advantages of biaxial apparatuses, i.e., simple geometry, high normal forces, confining pressure and pore fluid pressure, and the advantages of the rotary shear apparatuses, i.e. high slip velocity implemented thanks to the presence of electromagnetic motors. Building on the design of recent low-velocity biaxial machines implemented with pressure vessels (Samuelson et al. 2009; Collettini et al. 2014) and implementing the system with powerful linear motors (Di Toro et al. 2010), the new HighSTEPS (High Strain TEmperature Pressure Speed) apparatus is able to reproduce the deformation conditions typical of the seismogenic crust, i.e., confining pressure up to 100 MPa, slip velocity from 10–5 to 0.25 m/s, temperature up to 120 °C, pore pressure up to 100 MPa. Under these unique boundary conditions, the new apparatus allows the investigation of the entire seismic cycle (inter-seismic, nucleation and propagation).

Description: Published

Description: 2039–2052

Description: 3T. Fisica dei terremoti e Sorgente Sismica

Description: JCR Journal

Description: Endemic Antarctic macroalgae are especially adapted to live in extreme Antarctic conditions. Their potential biogeographic distribution niche is primarily controlled by the photoperiodic regime and seawater temperatures, since these parameters regulate growth, reproduction, and survival during the entire life cycle. Here we analyzed the upper survival temperature (UST) of juvenile sporophytes and the temperature range for sporophyte formation from gametophytes of Desmarestia menziesii, one of the dominant endemic Antarctic brown algal species. This process is a missing link to better evaluate the full biogeographical niche of this species. Two laboratory experiments were conducted. First, growth and maximum quantum yield of juvenile sporophytes were analyzed under a temperature gradient (0, 5, 10, 12, 13, 14, 15, and 16 °C) in a 16:8 h light:dark (LD) regime (Antarctic spring condition) for 2 weeks. Second, the formation of sporophytes from gametophytes (as a proxy of gametophyte reproduction) was evaluated during a 7 weeks period under a temperature gradient (0, 4, 8, 12, and 16 °C), and two different photoperiods: 6:18 h LD regime simulating winter conditions and a light regime simulating the Antarctic shift from winter to spring by gradually increasing the light period from 7.5:16.5 h LD (late winter) to 18.5:5.5 h LD (late spring). Sporophytes of D. menziesii were able to grow and survive up to 14 °C for 2 weeks without visible signs of morphological damage. Thus, this species shows the highest UST of all endemic Antarctic Desmarestiales species. In turn, gametophyte reproduction solely took place at 0 °C but not at 4–8 °C. The number of emerging sporophytes was six times higher under the light regime simulating the transition from winter to spring than under constant short day winter conditions. There was a negative relationship between the number of sporophytes formed and the gametophyte density at the beginning of the experiment, which provides evidence that gametophyte density exerts some control upon reproduction in D. menziesii. Results strongly indicate that although sporophytes and gametophytes may survive in warmer temperatures, the northernmost distribution limit of D. menziesii in South Georgia Islands is set by the low temperature requirements for gametophyte reproduction. Hence, global warming could have an impact on the distribution of this and other Antarctic species, by influencing their growth and reproduction.

Description: On 30 October 2020 a MW 7.0 earthquake occurred in the eastern Aegean Sea, between the Greek island of Samos and Turkey’s Aegean coast, causing considerable seismic damage and deaths, especially in the Turkish city of Izmir, approximately 70 km from the epicenter. In this study, we provide a detailed description of the Samos earthquake, starting from the fault rupture to the ground motion characteristics. We first use Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS) data to constrain the source mechanisms. Then, we utilize this information to analyze the ground motion characteristics of the mainshock in terms of peak ground acceleration (PGA), peak ground velocity (PGV), and spectral pseudo-accelerations. Modelling of geodetic data shows that the Samos earthquake ruptured a NNE-dipping normal fault located offshore north of Samos, with up to 2.5-3 m of slip and an estimated geodetic moment of 3.3 ⨯ 1019 Nm (MW 7.0). Although low PGA were induced by the earthquake, the ground shaking was strongly amplified in Izmir throughout the alluvial sediments. Structural damage observed in Izmir reveals the potential of seismic risk due to the local site effects. To better understand the earthquake characteristics, we generated and compared stochastic strong ground motions with the observed ground motion parameters as well as the ground motion prediction equations (GMPEs), exploring also the efficacy of the region-specific parameters which may be used to better predict the expected ground shaking from future large earthquakes in the region.

Description: Published

Description: 4745–4771

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: JCR Journal

Description: The China Seismo-Electromagnetic Satellite (CSES), China’s first satellite to measure geophysical fields with scientific goals in both space and solid earth physics, was launched successfully in February 2018. It carries high-precision magnetometers to measure the geomagnetic field. In this study, the CSES magnetic data were used to extract the signal of the lithospheric magnetic field caused by magnetized rocks in the crust and uppermost mantle. First, an along-track analysis of the CSES magnetic data was undertaken near the Bangui magnetic anomaly in central Africa and the Tarim magnetic anomaly in China, demonstrating that the CSES magnetic data are indeed sensitive to the lithospheric magnetic anomaly field. Then a lithospheric magnetic anomaly map over China and surrounding regions was derived. This map is consistent with the lithospheric part of the CHAOS-7 model. In particular, it clearly reveals four major magnetic anomalies containing long-wavelength signals at the altitude of Low-Earth-Orbiting satellites. Three magnetic highs are located over the Tarim, Sichuan and Songliao basin, the origins of which could be related to large-scale tectonic-magmatic activities during geological history. A prominent magnetic low is otherwise found in the southern Himalayan-Tibetan plateau, possibly caused by the shallow Curie depth in this region. To further improve the precision of the lithospheric magnetic field model, more detailed data processing and multi-source data merging are needed.

Description: Published

Description: 1118–1126

Description: 1A. Geomagnetismo e Paleomagnetismo

Description: JCR Journal

Description: Porous carbons are materials of wide application and their request is more and more increasing in the last years: Properly designed synthesis is presently available for the preparation of materials to be used in several fields (e.g.: adsorption, molecular separation, and catalysis). The characterization of the porous carbons is usually carried out using different techniques such as thermogravimetric analyses, Raman spectroscopy, Scanning electron microscopy, etc. In this work, the micro-Raman technique is adopted in combination with N2 physisorption at 77 K to monitor how the synthetic approach influences the presence of either amorphous or ordered regions in porous carbons. The typical D and G Raman bands of activated carbons have been carefully deconvoluted in six different components by a fitting procedure, and the determined R1 = ID1/IG ratio correlated to their specific surface area.

Description: Published

Description: 419–431

Description: 1TR. Georisorse

Description: JCR Journal

Description: The aim of this study is to improve our knowledge of the attenuation structure in the Southern Apennines using a new amplitude ratio tomography method (Phillips et al., Geophys Res Lett 32(21): L21301, 2005) applied on both direct and coda envelope measurements derived from 150 events recorded by 47 stations of the Istituto Nazionale di Geofisica e Vulcanologia National Seismic Network (Rete Sismica Nazionale Centralizzata). The twodimensional (2-D) analysis allows us to take into account lateral crustal variations and heterogeneities of this region. Using the same event and station distribution, we also applied a simple 1-D methodology, and the performance of the 1-D and 2-D path assumptions is tested by comparing the average interstation variance for the path-corrected amplitudes using coda and direct waves. In general, coda measurement results are more stable than using direct waves when the same methodology is applied. Using the 2-D approach, we observe more stable results for both waves. However, the improvement is quite small, probably because the crustal heterogeneity is weak. This means that, for this region, the 1-D path assumption is a good approximation of the attenuation characteristics of the region. A comparison between Q tomography images obtained using direct and coda amplitudes shows similar results, consistent with the geology of the region. In fact, we observe low Q along the Apennine chain toward the Tyrrhenian Sea and higher values to the east, in correspondence with the Gargano zone that is related to the Apulia Carbonate Platform. Finally, we compared our results with the coda Q values proposed by Bianco et al. (Geophys J Int 150:10–22, 2002) for the same region. The good agreement validates our results as the authors used a completely independent methodology.

Description: Published

Description: 355–365

Description: 1T. Struttura della Terra

Description: JCR Journal

Description: The petrological study of volcanic products emitted during the paroxysmal events of December 2015 from the summit craters of Mount Etna allow us to constrain T-P-XH2O phase stability, crystallization conditions, and mixing processes along the main open-conduit feeding system. In this study, we discuss new geochemical, thermo-barometric data and related Rhyolite- MELTS modelling of the eruptive activity that involved the concomitant activation of all summit craters. The results, in comparison with the previous paroxysmal events of the 2011–2012, reinforce the model of a vertically extended feeding system and highlight that the activity at the New South-East Crater was fed by magma residing at a significantly shallower depth with respect to the Central Craters (CC) and North-East Crater (NEC), even if all conduits were fed by a common deep (P = 530–440 MPa) basic magmatic input. Plagioclase dissolution, resorption textures, and the Rhyolite-MELTS stability model corroborate its dependence on H2O content; thus, suggesting that further studies on the effect that flushing from fluids with different H2O/ CO2 ratio are needed to understand the eruption-triggering mechanisms for high energetic strombolian paroxysmal episodes.

Description: Published

Description: 88

Description: 2V. Struttura e sistema di alimentazione dei vulcani

Description: 4V. Processi pre-eruttivi

Description: JCR Journal

Description: Validation and benchmarking of pyroclastic current (PC) models is required to evaluate their performance and their reliability for hazard assessment. Here, we present results of a benchmarking initiative built to evaluate four models commonly used to assess concentrated PC hazard: SHALTOP, TITAN2D, VolcFlow, and IMEX_SfloW2D. The benchmark focuses on the simulation of channelized flows with similar source conditions over five different synthetic channel geometries: (1) a flat incline plane, (2) a channel with a sharp 45° bend, (3) a straight channel with a break-in-slope, (4) a straight channel with an obstacle, and (5) a straight channel with a constriction. Several outputs from 60 simulations using three different initial volume fluxes were investigated to evaluate the performance of the four models when simulating valley-confined PC kinematics, including overflows induced by topographic changes. Quantification of the differences obtained between model outputs at t = 100 s allowed us to identify (1) issues with the Voellmy-Salm implementation of TITAN2D and (2) small discrepancies between the three other codes that are either due to various curvature and velocity formulations and/or numerical frameworks. Benchmark results were also in agreement with field observations of natural PCs: a sudden change in channel geometries combined with a high-volume flux is key to generate overflows. The synthetic benchmarks proved to be useful for evaluating model performance, needed for PC hazard assessment. The overarching goal is to provide an interpretation framework for volcanic mass flow hazard assessment studies to the geoscience community.

Description: Published

Description: 75

Description: 5V. Processi eruttivi e post-eruttivi

Description: JCR Journal

Description: Deciphering magma evolution below ocean basaltic volcanoes is all the more challenging because magma mixing is a common process tending to modify the pristine geochemical diversity during magma ascent. On the western flank of the Piton de la Fournaise volcano, transitional basalts have compositions that testify to origins down to the upper mantle and display a widespread geochemical diversity ranging from a tholeiitic affinity to an alkaline one. There, we show that evolved melt inclusions and matrix glasses (MgO 〈 9 wt%) record an alkali enrichment coupled with a Ca/Al ratio decrease, which tracks the effect of clinopyroxene crystallization at the depth of the mantle-crust underplating layer. At this depth and shallower, reverse zoning of olivine crystals, clinopyroxene dissolution, and hybrid melt compositions testify to extensive mixing processes leading to a homogenization of the pristine geochemical footprint of melts upon ascent. Enrichment in incompatible trace elements in some evolved melt inclusions suggests that magma ponding at the depth of the mantle-crust underplating layer favours also assimilation of melts originating from low degrees of partial melting of cumulates (wehrlites, dunites). Conversely, the most primitive melt inclusions documented so far at La Réunion Island (MgO up to 11.2 wt%) better preserve a pristine geochemical variability related to partial melting of a slightly heterogeneous mantle source. We suggest that these slightly distinct source components may mirror the compositions of recent melts from the two closely located Piton de la Fournaise and Piton des Neiges volcanoes.

Description: Published

Description: 84

Description: 2V. Struttura e sistema di alimentazione dei vulcani

Description: 4V. Processi pre-eruttivi

Description: JCR Journal

Description: We used 1029 earthquakes, with magnitudes ranging from M 3.0 to M 6.5, located in central Apennines, Italy, and recorded by 414 local stations to study the variation of the quality factor QS of shear waves with depth. We first determined average nonparametric attenuation functions in the frequency band from 0.5 to 20 Hz and hypocenter distances less than 155 km to correct the observed acceleration spectra for attenuation effects. Then, we separated source and site effects from the corrected spectral records to determine the changes of QS with depth. We used a 1D local shear-wave velocity model to calculate the travel times of the source-station paths, and we inverted the observed spectra to determine QS in three different depth intervals (0–4 km, 4–10 km and 10–15 km) and five frequencies (0.5, 1, 4, 10 and 20 Hz). We found that QS increases with frequency at all depths considered and tends to have lower values at shallow depths. The average value of QS is consistent with previous studies made in central Italy and can be approximated by QS = 43f0.94. To describe the frequency dependence of QS with depth (H), we determine the following relations: QS = 5.5f1.39, 0.5 ≤ f ≤ 10 Hz and QS = 151.5, f 〉 10 Hz for 0–4 km, QS = 52f0.87 for 4 〈 H 〈 10 km and QS = 51f0.92 for 10 ≤ H ≤ 15 km. We conclude that the Q-depth-dependent model can be useful to improve estimates of source parameters and ground motion prediction in the central Apennines region of Italy.

Description: Published

Description: 2059–2075

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: JCR Journal

Description: Correction to: Natural Hazards https://doi.org/10.1007/s11069-021-04675-z

Description: Correction to: Natural Hazards https://doi.org/10.1007/s11069-021-04675-z

Description: Published

Description: 203

Description: 3T. Fisica dei terremoti e Sorgente Sismica

Description: JCR Journal

Description: Physics-based broadband ground-motion simulations are generated for the strong mainshocks that occurred in the region of the Central Ionian Islands, on 26th January 2014 in Kefalonia (Mw6.1) and 17th November 2015 in Lefkas (Mw6.5). The study area is associated with frequent strong earthquakes both in the historical and instrumental eras. During the last decades, the network of strong-motion accelerographs in the area has been densified, and thus provided an adequate number of strong ground-motion records as a means to better examine the related ground-motion characteristics. In the present study, broadband ground motions for the two case studies are simulated both at selected sites and at a dense grid of points covering the affected areas. The low-frequency part of the synthetics is computed using a discrete wavenumber finite element method by convolving Green’s functions with a kinematic slip model in the frequency domain. A stochastic finite fault model approach based on a dynamic corner frequency is considered to calculate the ground motions for the higher frequencies. The broadband synthetic time series are generated after merging the results obtained from the two separate techniques, by performing a weighted summation at intermediate frequencies. The simulated values are validated by comparison with both recorded Peak Ground Acceleration (PGA) and PeakGround Velocity (PGV) values and the estimated ones by using widely accepted Ground Motion Prediction Equations (GMPEs). Our results indicate that both the spatial distribution and the amplification pattern of the simulated ground motions, in the near-field, in terms of PGA and PGV are highly influenced by the slip heterogeneity and the maximum slip patches within the seismic source.

Description: Published

Description: 3505–3527

Description: 6T. Studi di pericolosità sismica e da maremoto

Description: JCR Journal

Description: Stromboli is an active, open conduit mafic volcano, whose persistent mild Strombolian activity is occasionally punctuated by much stronger explosions, known as paroxysms. During summer 2019, the volcano unexpectedly produced one such paroxysm on July 3, followed by intense explosive and intermittent effusive activity culminating in a second paroxysm on August 28. Visual observations and the analysis of the fall deposits associated with the two paroxysms allowed us to reconstruct ballistic exit velocities of up to 160 m s−1. Plume heights of ~ 8.4 km and 6.4 km estimated for the two events correspond to mass eruption rates of 1.1 x 10 6 kg s−1 and 3.6 x 105 kg s−1, respectively. This is certainly an underestimate as directional pyroclastic flows into which mass was partitioned immediately formed, triggering small tsunamis at the sea entrance. The mass of ballistic spatters and blocks erupted during the July 3 event formed a continuous cover at the summit of the volcano, with a mass calculated at ~ 1.4 x 10 8 kg. The distribution of fall deposits of both the July 3 and August 28 events suggests that pyroclasts characterized by terminal fall velocities 〈 10–20 m s−1 remained fully suspended within the convective region of the plume and did not fall at distances closer than ca 1700 m to the vent. Based on the impulsive, blast-like phenomenology of paroxysms as well as the deposit distribution and type, paroxysms are classified as basaltic Vulcanian in style. The evolution of the summer 2019 eruptive events was not properly captured within the framework of the alert level system which is focused on tsunamigenic processes, and this is discussed so as to provide elements for the implementation of the reference scenarios and an upgrade of the system to take into account such events. In particular we find that, although still largely unpredictable, at least at operational time scales, and not necessarily tsunamigenic, Vulcanian eruptions and the subsequent evolution of the eruptive phenomena should be considered for the alert level system. This serves as a warning to the implementation of alert systems where the unexpected needs to be taken into account, even at systems that are believed to be relatively “predictable” as is the case at many persistently active, open vent mafic systems.

Description: Published

Description: 1

Description: 5V. Processi eruttivi e post-eruttivi

Description: JCR Journal

Description: This paper reports on experiments devoted to explore the role of specific attributes of humanoid virtual agents that may influence elderly users’ perception and attitude, determining their acceptance and adoption as assistive devices. In particular, it investigates elderly preference on agents’ gender and the role of the agents’ ability to use voice during the interaction. To this aim two different groups of seniors were involved in the experiments. The first group evaluated talking virtual agents, the second one the same virtual agents, but silenced. The data shows that elderly users, independently from their gender, prefer to interact with female agents, especially when they are able to talk to them, revealing the role played by the voice. Furthermore, it was found a significant effect of the elderly level of experience with technology: when interacting with agents with voice, elderly users with high technological experience were less interested and considered the proposed agents less attractive and appealing, while just the opposite occurred when interacting with silenced agents.

Description: Published

Description: 4429–4436

Description: 5TM. Informazione ed editoria

Description: JCR Journal

Description: Risk assessments in volcanic contexts are complicated by the multi-hazard nature of both unrest and eruption phases, which frequently occur over a wide range of spatial and temporal scales. As an attempt to capture the multi-dimensional and dynamic nature of volcanic risk, we developed an integrAteD VolcanIc risk asSEssment (ADVISE) model that focuses on two temporal dimensions that authorities have to address in a volcanic context: short-term emergency management and long-term risk management. The output of risk assessment in the ADVISE model is expressed in terms of potential physical, functional, and systemic damage, determined by combining the available information on hazard, exposed systems and vulnerability. The ADVISE model permits qualitative, semi-quantitative and quantitative risk assessment depending on the final objective and on the available information. The proposed approach has evolved over a decade of study on the volcanic island of Vulcano (Italy), where recent signs of unrest combined with uncontrolled urban development and significant seasonal variations of exposed population result in highly dynamic volcanic risk. For the sake of illustration of all the steps of the ADVISE model, we focus here on the risk assessment of the transport system in relation to the tephra fallout associated with a long-lasting Vulcanian cycle.

Description: Published

Description: 7

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: N/A or not JCR

Description: The Campi Flegrei volcano (or Phlegraean Fields), Campania, Italy, generated the largest eruption in Europe in at least 200 ka. Here we summarise the volcanic and human history of Campi Flegrei and discuss the interactions between humans and the environment within the “burning felds” from around 10,000 years until the 1538 CE Monte Nuovo eruption and more recent times. The region’s incredibly rich written history documents how the landscape changed both naturally and anthropogenically, with the volcanic system fuelling these considerable natural changes. Humans have exploited the beautiful landscape, accessible resources (e.g. volcanic ash for pulvis puteolana mortar) and natural thermal springs associated with the volcano for millennia, but they have also endured the downsides of living in a volcanically active region—earthquakes, signifcant ground deformation and landscape altering eruptions. The pre-historic record is detailed, and various archaeological sites indicate that the region was certainly occupied in the last 10,000 years. This history has been reconstructed by identifying archaeological fnds in sequences that often contain ash (tephra) layers from some of the numerous volcanic eruptions from Campi Flegrei and the other volcanoes in the region that were active at the time (Vesuvius and Ischia). These tephra layers provide both a relative and absolute chronology and allow the archaeology to be placed on a relatively precise timescale. The records testify that people have inhabited the area even when Campi Flegrei was particularly active.The archaeological sequences and outcrops of pyroclastic material preserve details about the eruption dynamics, buildings from Roman times, impressive craters that now host volcanic lakes and nature reserves, all of which make this region particularly mystic and fascinating, especially when we observe how society continues to live within the active caldera system. The volcanic activity and long record of occupation and use of volcanic resources in the region make it unique and here we outline key aspects of its geoheritage.

Description: Published

Description: 5

Description: 1V. Storia eruttiva

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: 6SR VULCANI – Servizi e ricerca per la società

Description: JCR Journal

Description: Here, we report on the Quaternary Volsci Volcanic Field (VVF, central Italy). In light of new 40Ar/39Ar geochronological data and compositional characterization of juvenile eruptive products, we refine the history of VVF activity, and outline the implications on the pre-eruptive magma system and the continental subduction processes involved. Different from the nearby volcanic districts of the Roman and Campanian Provinces, the VVF was characterized by small-volume (0.01–0.1 km3) eruptions from a network of monogenetic centers (mostly tuff rings and scoria cones, with subordinate lava occurrences), clustered along high-angle faults of lithospheric depth. Leucite-bearing, high-K (HKS) magmas (for which we report for the first time the phlogopite phenocryst compositions) mostly fed the early phase of activity (∼761–539 ka), then primitive, plagioclase-bearing (KS) magmas appeared during the climactic phase (∼424–349 ka), partially overlapping with HKS ones, and then prevailed during the late phase of activity (∼300–231 ka). The fast ascent of primitive magma batches is typical of a tectonically controlled volcanic field, where the very low magma flux is a passive byproduct of regional tectonic strain. We suggest that the dominant compressive stress field acting at depth was accompanied by an extensional regime in the upper crust, associated with the gravity spreading of the Apennine chain, allowing the fast ascent of magma from the mantle source with limited stationing in shallow reservoirs.

Description: Published

Description: 689–718

Description: 1V. Storia eruttiva

Description: JCR Journal

Description: Numerical results of a two-layer depth-averaged model of pyroclastic density currents (PDCs) were compared with an experimental PDC generated at the international eruption simulator facility (the Pyroclastic flow Eruption Large-scale Experiment (PELE)) to establish a minimal dynamical model of PDCs with stratification of particle concentrations. In the present two-layer model, the stratification in PDCs is modeled as a voluminous suspended-load layer with low particle volume fractions ( ≲ 10−3) and a thin basal bed-load layer with higher particle volume fractions ( ∼ 10−2 ) on the basis of the source condition in the experiment. Numerical results for the suspended load quantitatively reproduce the time evolutions of the front position and flow thickness in the experimental PDC. The numerical results of the bed-load and deposit thicknesses depend on an assumed value of settling speed at the bottom of the bed load ( WsH ). We show that the thicknesses of bed load and deposit in the simulations agree well with the experimental data, when WsH is set to about 1.25 × 10−2 m/s. This value of the settling speed is two orders of magnitude smaller than that predicted by a hindered-settling model. The small value of WsH is considered to result from decreasing in the effective deposition speed due to the erosion process accompanied by saltating/rolling of particles at the bottom of the bed load.

Description: Published

Description: 73

Description: 5V. Processi eruttivi e post-eruttivi

Description: JCR Journal

Description: A new analysis of high-resolution multibeam and seismic reflection data, collected during several oceanographic expeditions starting from 1999, allowed us to compile an updated morphotectonic map of the North Anatolian Fault below the Sea of Marmara. We reconstructed kinematics and geometries of individual fault segments, active at the time scale of 10 ka, an interval which includes several earthquake cycles, taking as stratigraphic marker the base of the latest marine transgression. Given the high deformation rates relative to sediment supply, most active tectonic structures have a morphological expression at the seafloor, even in presence of composite fault geometries and/or overprinting due to mass-wasting or turbidite deposits. In the frame of the right-lateral strike-slip domain characterizing the North Anatolian fault system, three types of deformation are observed: almost pure strike-slip faults, oriented mainly E–W; NE/SW-aligned axes of transpressive structures; NW/SE-oriented trans-tensional depressions. Fault segmentation occurs at different scales, but main segments develop alongthree major right-lateral oversteps, which delimit main fault branches, from east to west: (i) the transtensive Cinarcik segment; (ii) the Central (East and West) segments; and (iii) the westernmost Tekirdag segment. A quantitative morphometric analysis of the shallow deformation patterns observed by seafloor morphology maps and high-resolution seismic reflection profiles along the entire basin allowed to determine nature and cumulative lengths of individual fault segments. These data were used as inputs for empirical relationships, to estimate maximum expected Moment Magnitudes, obtaining values in the range of 6.8–7.4 for the Central, and 6.9–7.1 for the Cinarcik and Tekirdag segments, respectively. We discuss these findings considering analyses of historical catalogues and available paleoseismological studies for the Sea of Marmara regionto formulate reliable seismic hazard scenarios.

Description: Published

Description: 29–44

Description: 6T. Studi di pericolosità sismica e da maremoto

Description: N/A or not JCR

Description: Future occurrence of explosive eruptive activity at Cotopaxi and Guagua Pichincha volcanoes, Ecuador, is assessed probabilistically, utilizing expert elicitation. Eight eruption types were considered for each volcano. Type event probabilities were evaluated for the next eruption at each volcano and for at least one of each type within the next 100 years. For each type, we elicited relevant eruption source parameters (duration, average plume height, and total tephra mass). We investigated the robustness of these elicited evaluations by deriving probability uncertainties using three expert scoring methods. For Cotopaxi, we considered both rhyolitic and andesitic magmas. Elicitation findings indicate that the most probable next eruption type is an andesitic hydrovolcanic/ash-emission (~ 26–44% median probability), which has also the highest median probability of recurring over the next 100 years. However, for the next eruption at Cotopaxi, the average joint probabilities for sub-Plinian or Plinian type eruption is of order 30–40%—a significant chance of a violent explosive event. It is inferred that any Cotopaxi rhyolitic eruption could involve a longer duration and greater erupted mass than an andesitic event, likely producing a prolonged emergency. For Guagua Pichincha, future eruption types are expected to be andesitic/dacitic, and a vulcanian event is judged most probable for the next eruption (median probability ~40–55%); this type is expected to be most frequent over the next 100 years, too. However, there is a substantial probability (possibly 〉40% in average) that the next eruption could be sub-Plinian or Plinian, with all that implies for hazard levels.

Description: Published

Description: 35

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: JCR Journal

Description: Exposure to volcanic ash is a long-standing health concern for people living near active volcanoes and in distal urban areas. During transport and deposition, ash is subjected to various physicochemical processes that may change its surface composition and, consequently, bioreactivity. One such process is the interaction with anthropogenic pollutants; however, the potential for adsorbed, deleterious organic compounds to directly impact human health is unknown. We use an in vitro bioanalytical approach to screen for the presence of organic compounds of toxicological concern on ash surfaces and assess their biological potency. These compounds include polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzop- dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dlPCBs). Analysis of ash collected in or near urbanised areas at five active volcanoes across the world (Etna, Italy; Fuego, Guatemala; Kelud, Indonesia; Sakurajima, Japan; Tungurahua, Ecuador) using the bioassay inferred the presence of such compounds on all samples. A relatively low response to PCDD/Fs and the absence of a dlPCBs response in the bioassay suggest that the measured activity is dominated by PAHs and PAH-like compounds. This study is the first to demonstrate a biological potency of organic pollutants associated with volcanic ash particles. According to our estimations, they are present in quantities below recommended exposure limits and likely pose a low direct concern for human health.

Description: Published

Description: 30

Description: 7SR AMBIENTE – Servizi e ricerca per la società

Description: JCR Journal

Description: Correction to: Bulletin of Earthquake Engineering https://doi.org/10.1007/s10518-021-01077-1

Description: Published

Description: 3317

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: JCR Journal

Description: Poás is a complex stratovolcano with an altitude of 2,708 m asl, located in the Cordillera Volcánica Central of Costa Rica. Prior to 2017, the last three historical eruptions occurred on 7 February 1834, between January and May 1910 and during the period 1953-1955. Very few literature exists on the 1834 eruption. The only references state that it was an important event, that ash reached 〉53 km W-SW of Poás, and that it harmed the grasslands around the volcano. Related deposits of this eruption suggest phreatic activity, which launched bombs and blocks. Moreover, there is evidence of pyroclastic flow deposits near the crater. The 1910 eruption is better described. Despite the fact that ash fall is only reported near the volcano, a volume of the deposit of 1.6 x 107 m3 is estimated. Deposits of the eruption are white in color with many hydrothermally altered, and minor presence of juvenile fragments (vesicular lapilli). The eruption is classified as vulcanian, with deposits of ash fall and pyroclastic flows close to the crater. A Volcano Explosivity Index 3 (VEI 3) is estimated. The eruption affected agriculture. The 1953-1955 eruptions had a longer duration. Various ash fall deposits at several sites are reported. Deposits of this eruption, easily distinguished in the field, are black scoria lapilli, bombs with, sometimes fusiform, bread crust textures. In the eastern sector of the crater bombs can reach meters in size; such large bombs near the eruption centre at one side suggest the inclination of the eruptive conduct, or an asymmetrical vent-crater system. Inside the crater a 40 m-high dome and a lava flow were extruded during the eruption. Towards the east side of the current Laguna Caliente crater lake, relicts of a 8.5 m thick lava pool are found. During the entire eruptive episode, the acid lake presumably lacked. The eruption is described to be of a mixed type: strombolian, phreatomagmatic, vulcanian and dome extrusion eruptions. Considering the characteristics of this eruption, the height of the eruption column, ejected volume (2.1 x 107  m3), and its presumed duration, a VEI 3 is estimated. The eruptions damaged agricultural activity (including cattle), and forced the spontaneous evacuation of some people. In April 2017 magmatic eruptions followed a decade-long period of intense phreatic activity. These eruptions destroyed the 1953-1955 Dome and led to the complete dry out of Laguna Caliente. Pyroclastic cones and sulphur volcanism manifested at the bottom of the former crater lake bottom. The 2017 eruption severely affected touristic activities at and near Poás, with an estimated economic loss of 20 million dollars. By May-August 2018 Laguna Caliente reappeared. The volcanic hazards related to the three studied historical eruptions are: pyroclastic flows (at least 1 km from the eruptive centre, including reaching the current mirador sector), ballistics (bomb ejections up to 2 km from the emission centre), dispersion and fall of pyroclasts (tens of kms), gas emission and acid rain, dispersed by WSW dominant winds, and lahars in most of the river canyons SW of the volcano.  

Description: Published

Description: 261-299

Description: 1V. Storia eruttiva

Description: Integrating palaeoclimatological proxies and historical records, which is necessary to achieve a more complete understanding of climate impacts on past societies, is a challenging task, often leading to unsatisfactory and even contradictory conclusions. This has until recently been the case for Italy, the heart of the Roman Empire, during the transition between Antiquity and the Middle Ages. In this paper, we present new high-resolution speleothem data from the Apuan Alps (Central Italy). The data document a period of very wet conditions in the sixth c. AD, probably related to synoptic atmospheric conditions similar to a negative phase of the North Atlantic Oscillation. For this century, there also exist a significant number of historical records of extreme hydroclimatic events, previously discarded as anecdotal. We show that this varied evidence reflects the increased frequency of floods and extreme rainfall events in Central and Northern Italy at the time. Moreover, we also show that these unusual hydroclimatic conditions overlapped with the increased presence of "water miracles" in Italian hagiographical accounts and social imagination. The miracles, performed by local Church leaders, strengthened the already growing authority of holy bishops and monks in Italian society during the crucial centuries that followed the "Fall of the Roman Empire". Thus, the combination of natural and historical data allows us to show the degree to which the impact of climate variability on historical societies is determined not by the nature of the climatic phenomena per se, but by the culture and the structure of the society that experienced it.

Description: Published

Description: 25

Description: 5A. Ricerche polari e paleoclima

Description: JCR Journal

Description: Volcano-hydrothermal systems are governed by complex interactions between fluid transport, and geochemical and mechanical processes. Evidence of this close interplay has been testified by distinct spatial and temporal correlations in geochemical and geophysical observations at Vulcano Island (Italy). To understand the interaction between fluid circulation and the geochemical and geophysical manifestations, we perform a parametric study to explore different scenarios by implementing a hydro-geophysical model based on the equations for heat and mass transfer in a porous medium and thermo-poroelastic theory. Numerical simulations allow us to define the controlling role of permeability distribution on the different modeled parameters as well as on the geophysical observables. Changes in the permeability within the highly fractured crater area could be responsible for the fluctuations in gas emission and temperature recorded during the crisis periods, which are accompanied by shallow volcano-seismicity in the absence of significant deformation and gravity variations. Despite the general medium permeability of the volcanic edifice, the presence of more highly permeable pathways, which allow the gas to rapidly escape, as testified by the presence of a well-developed fumarolic field, prevents the pressure buildup at shallow depths.

Description: Published

Description: 179

Description: 4V. Processi pre-eruttivi

Description: JCR Journal

Description: Lahars are rapid flows composed of water and volcaniclastic sediments, which have the potential to impact residential buildings and critical infrastructure as well as to disrupt critical services, especially in the absence of hazard-based land-use planning. Their destructive power is mostly associated with their velocity (related to internal flow properties and topographic interactions) and to their ability to bury buildings and structures (due to deposit thickness). The distance reached by lahars depends on their volume, on sediments/water ratio, as well as on the geometrical properties of the topography where they propagate. Here we present the assessment of risk associated with lahar using Vulcano island (Italy) as a case study. First, we estimated an initial lahar source volume considering the remobilisation by intense rain events of the tephra fallout on the slopes of the La Fossa cone (the active system on the island), where the tephra fallout is associated with the most likely scenario (e.g. long-lasting Vulcanian cycle). Second, we modelled and identified the potential syn-eruptive lahar impact areas on the northern sector of Vulcano, where residential and touristic facilities are located. We tested a range of parameters (e.g., entrainment capability, consolidation of tephra fallout deposit, friction angle) that can influence lahar propagation output both in terms of intensity of the event and extent of the inundation area. Finally, exposure and vulnerability surveys were carried out in order to compile exposure and risk maps for lahar-flow front velocity (semi-quantitative indicator-based risk assessment) and final lahar-deposit thickness (qualitative exposure-based risk assessment). Main outcomes show that the syn-eruptive lahar scenario with medium entrainment capability produces the highest impact associated with building burial by the final lahar deposit. Nonetheless, the syn-eruptive lahar scenario with low entrainment capacity is associated with higher runout and results in the highest impact associated with lahar-flow velocities. Based on our simulations, two critical infrastructures (telecommunication and power plant), as well as the main road crossing the island are exposed to potential lahar impacts (either due to lahar-flow velocity or lahar-deposit thickness or both). These results show that a risk-based spatial planning of the island could represent a valuable strategy to reduce the volcanic risk in the long term.

Description: Published

Description: 9

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: N/A or not JCR

Description: Recent studies point to the sensitivity of mid-latitude winter climate to Arctic sea ice variability. However, there remain contradictory results in terms of character and timing of Northern Hemisphere large-scale circulation features to Arctic sea ice changes. This study assesses the impact of realistic late autumn eastern Arctic sea ice anomalies on atmospheric wintertime circulation at mid-latitudes, pointing to a hidden potential for seasonal predictability. ​Using a dynamical seasonal prediction system, an ensemble of seasonal forecast simulations of 23 historical winter seasons is run with reduced November sea ice cover in the Barents-Kara Seas, and is compared to the respective control seasonal hindcast simulations set. ​A non energy-conserving approach is adopted for achieving the desired sea ice loss, with artificial heat being added conditionally to the ocean surface heat fluxes so as to inhibit the formation of sea ice during November. Our results point to a robust atmospheric circulation response in the North Pacific sector, similar to previous findings on the multidecadal timescale. Specifically, an anticyclonic anomaly at upper and lower levels is identified over the eastern midlatitude North Pacific, leading to dry conditions over the North American southwest coast. The responses are related to a re-organization (weakening) of west-Pacific tropical convection and interactions with the tropical Hadley circulation. ​A possible interaction of the poleward-shifted Pacific eddy-driven jet stream and the Hadley cell is discussed​. ​The winter circulation response in the Euro-Atlantic sector is ephemeral in character and statistically significant in January only, corroborating previous findings of an intermittent and non-stationary Arctic sea ice-NAO link during boreal winter. These results ​aid our understanding of the seasonal impacts of reduced eastern Arctic sea ice on the midlatitude atmospheric circulation with implications for seasonal predictability in wintertime.

Description: Published

Description: 2687–2700

Description: 4A. Oceanografia e clima

Description: JCR Journal

Description: Gender equality is a fundamental human right, embedded into the United Nations Charter (1945). Women still face multiple forms of discrimination, harassment and abuse. Gender equality is foundational to ensuring inclusive sustainable socio-economic development, peace and justice.

Description: Published

Description: 105-126

Description: 1TM. Formazione

Description: 3TM. Comunicazione

Description: Hydrogeoethics is an emergent transdisciplinary field in geosciences focused on ethical research and best practices related to responsible groundwater science and engineering, creating conditions for sustainable water resources management while respecting human needs and environmental dynamics.

Description: Published

Description: 289–292

Description: 1TR. Georisorse

Description: N/A or not JCR

Description: Groundwater close to three municipal solid waste landfll sites in Sicily (southern Italy) was sampled to determine the presence of contaminants and the risk associated with its possible use as drinking and sanitary water. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and metals were investigated. These target compounds are the most common pollutants present in leachates. Risk Assessment Guidance for Superfund (RAGS, US EPA) was used to assess human health risk. Ingestion, dermal, and total exposure to these xenobiotic contaminants in groundwater were evaluated, and the cancer and non-cancer risk indexes were calculated. The results revealed that, while the groundwater complied with Italian Drinking Water Directive 30/2001, it did not comply with the "good environmental state" criteria of Directive 30/2009 at two of the three sites investigated. Worrying results were revealed by the risk assessment at the investigated sites. Cancer and non-cancer risk indexes indicated a probable risk, mainly due to dermal exposure to groundwater. These results underline the importance of assessing the risk for all possible routes, evaluating not only ingestion but also dermal exposure, especially when organic pollutants are present. The results of this study show that human health risk has probably been underestimated in the past, as dermal exposure to organic pollutants has only rarely been evaluated in the literature.

Description: Published

Description: 535–550

Description: 6A. Geochimica per l'ambiente e geologia medica

Description: JCR Journal

Description: The island of Ischia, located in the Gulf of Naples, represents an unusual case of resur- gent caldera where small-to-moderate magnitude volcano-tectonic earthquakes generate large damage and catastrophic e ects, as in the case of 4 March 1881 (Imax-VIII-IXMCS) and 28 July 1883 (Imax X-XI MCS) historical earthquakes, and of the recent 21 August 2017 MW=3.9, event. All these earthquakes struck the northern area of the island. With about 65,000 inhabitants, Ischia is a popular touristic destination for thermals baths, host- ing more than 3,000,000 visitors per year, thus representing a high seismic risk area. Assessing its seismic potential appears a fundamental goal and, to this end, the estimate of the magnitude of signi cant historical events and the characterization of their source are crucial. We report here a reassessment of historical data of damage of 1881 and 1883 earth- quakes to evaluate the main source parameters of these events (obtained with the BOXER and EXISM software) and quantitatively compare, for the rst time, the results with the source characteristics, obtained from instrumental data, of the recent 2017 earthquake. The results allowed us to assess the location, as well as the possible dimension and the related maximum magnitude, of the seismogenic structure responsible for such damaging earth- quakes. Our results also provide an additional framework to de ne the mechanisms leading to earthquakes associated with the dynamics of calderas.

Description: Published

Description: 177–201

Description: 3T. Fisica dei terremoti e Sorgente Sismica

Description: JCR Journal

Description: The AD 1761 eruption on Terceira was the onlyhistorical subaerial event on the island and one of the lastrecorded in the Azores. The eruption occurred along the fis-sure zone that crosses the island and produced a trachybasaltlava flow and scoria cones. Small comenditic trachyte lava domes (known as Mistérios Negros) were also thought by some to have formed simultaneously on the eastern flank of Santa Bárbara Volcano. Following a multidisciplinary approach, we combined geological mapping, paleomagnetic, petrographic, mineral and whole-rock geochemical and structural analyses to study this eruption. The paleomagnetic dating method compared geomagnetic vectors (directions and intensities) recorded by both the AD 1761 lava flow and Mistérios Negros domes and revealed that the two events were indeed coeval. Based on new data and interpretation of historical records, we have accordingly reconstructed the AD 1761eruptive dynamics and distinguished three phases: (1) a pre-cursory phase characterized by decreased degassing in the fumarolic field of Pico Alto Volcano and a gradual increase of seismic activity, which marked the intrusion of trachybasalt magma; (2) a first eruptive phase that started with phreatic explosions on the eastern flank of Santa Bárbara Volcano, followed by the inconspicuous effusion of comenditic trachyte (66 wt% SiO2), forming a WNW-ESE-oriented chain of lava domes; and (3) a second eruptive phase on the central part ofthe fissure zone, where a Hawaiian to Strombolian-style erup-tion formed small scoria cones (E-W to ENE-WSW-oriented)and a trachybasalt lava flow (50 wt% SiO2) which buried 27houses in Biscoitos village. Petrological analyses show thatthe two batches of magma were emitted independently without evidence of interaction. We envisage that the dome-forming event was triggered by local stress changes induced by intrusion of the trachybasalt dyke along the fissure zone, which created tensile stress conditions that promoted ascent of comenditic trachyte magma stored beneath Santa Bárbara Volcano.

Description: Published

Description: 22

Description: 1A. Geomagnetismo e Paleomagnetismo

Description: JCR Journal

Description: We present an interdisciplinary review of the observed and projected variations in atmospheric and oceanic circulation within the southwestern South Atlantic focused on basin-scale processes driven by climate change, and their potential impact on the regional fisheries. The observed patterns of atmospheric circulation anomalies are consistent with anthropogenic climate change. There is strong scientific evidence suggesting that the Brazil Current is intensifying and shifting southwards during the past decades in response to changes in near-surface wind patterns, leading to intense ocean warming along the path of the Brazil Current, the South Brazil Bight, and in the Río de la Plata. These changes are presumably responsible for the poleward shift of commercially important pelagic species in the region and the long-term shift from cold-water to warm-water species in industrial fisheries of Uruguay. Scientific and traditional knowledge shows that climate change is also affecting small-scale fisheries. Long-term records suggest that mass mortalities decimated harvested clam populations along coastal ecosystems of the region, leading to prolonged shellfishery closures. More frequent and intense harmful algal blooms together with unfavorable environmental conditions driven by climate change stressors affect coastal shellfisheries, impact economic revenues, and damage the livelihood of local communities. We identify future modelling needs to reduce uncertainty in the expected effects of climate change on marine fisheries. However, the paucity of fisheries data prevents a more effective assessment of the impact of climate change on fisheries and hampers the ability of governments and communities to adapt to these changes.

Description: Growing evidence indicates that the atmospheric and oceanic circulation experiences a systematic poleward shift in a warming climate. However, the complexity of the climate system, including the coupling between the ocean and the atmosphere, natural climate variability and land-sea distribution, tends to obfuscate the causal mechanism underlying the circulation shift. Here, using an idealised coupled aqua-planet model, we explore the mechanism of the shifting circulation, by isolating the contributing factors from the direct CO2 forcing, the indirect ocean surface warming, and the wind-stress feedback from the ocean dynamics. We find that, in contrast to the direct CO2 forcing, ocean surface warming, in particular an enhanced subtropical ocean warming, plays an important role in driving the circulation shift. This enhanced subtropical ocean warming emerges from the background Ekman convergence of surface anomalous heat in the absence of the ocean dynamical change. It expands the tropical warm water zone, causes a poleward shift of the mid-latitude temperature gradient, hence forces a corresponding shift in the atmospheric circulation and the associated wind pattern. The shift in wind, in turn drives a shift in the ocean circulation. Our simulations, despite being idealised, capture the main features of the observed climate changes, for example, the enhanced subtropical ocean warming, poleward shift of the patterns of near-surface wind, sea level pressure, storm tracks, precipitation and large-scale ocean circulation, implying that increase in greenhouse gas concentrations not only raises the temperature, but can also systematically shift the climate zones poleward.

Description: © The Author(s), (2022). This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ahmed, D. A., Hudgins, E. J., Cuthbert, R. N., Kourantidou, M., Diagne, C., Haubrock, P. J., Leung, B., Liu, C., Leroy, B., Petrovskii, S., Beidas, A., & Courchamp, F. Managing biological invasions: the cost of inaction. Biological Invasions. (2022), https://doi.org/10.1007/s10530-022-02755-0.

Description: Ecological and socioeconomic impacts from biological invasions are rapidly escalating worldwide. While effective management underpins impact mitigation, such actions are often delayed, insufficient or entirely absent. Presently, management delays emanate from a lack of monetary rationale to invest at early invasion stages, which precludes effective prevention and eradication. Here, we provide such rationale by developing a conceptual model to quantify the cost of inaction, i.e., the additional expenditure due to delayed management, under varying time delays and management efficiencies. Further, we apply the model to management and damage cost data from a relatively data-rich genus (Aedes mosquitoes). Our model demonstrates that rapid management interventions following invasion drastically minimise costs. We also identify key points in time that differentiate among scenarios of timely, delayed and severely delayed management intervention. Any management action during the severely delayed phase results in substantial losses (〉50% of the potential maximum loss). For Aedes spp., we estimate that the existing management delay of 55 years led to an additional total cost of approximately $ 4.57 billion (14% of the maximum cost), compared to a scenario with management action only seven years prior (〈 1% of the maximum cost). Moreover, we estimate that in the absence of management action, long-term losses would have accumulated to US$ 32.31 billion, or more than seven times the observed inaction cost. These results highlight the need for more timely management of invasive alien species—either pre-invasion, or as soon as possible after detection—by demonstrating how early investments rapidly reduce long-term economic impacts.

Description: The authors acknowledge the French National Research Agency (ANR-14-CE02-0021) and the BNP-Paribas Foundation Climate Initiative for funding the InvaCost project that allowed the construction of the InvaCost database. The present work was conducted following a workshop funded by the AXA Research Fund Chair of Invasion Biology and is part of the AlienScenarios project funded by BiodivERsA and Belmont-Forum call 2018 on biodiversity scenarios. DAA is funded by the Kuwait Foundation for the Advancement of Sciences (KFAS), grant no. PR1914SM-01 and the Gulf University for Science and Technology (GUST) internal seed fund, grant no. 234597. EJH is supported by a Fonds de recherche du Québec—nature et téchnologies B3X fellowship. RNC acknowledges funding from the Alexander von Humboldt Foundation. CL was sponsored by the PRIME programme of the German Academic Exchange Service (DAAD) with funds from the German Federal Ministry of Education and Research (BMBF).

Description: The Riardo basin hosts groundwater exploited for the production of high quality, naturally sparkling, bottled water (e.g., Ferrarelle water), and circulating in a system constituted by highly fractured Mesozoic carbonates, overlain by more impervious volcanic rocks of the Roccamonfina complex. The two formations are locally in hydraulic connection and dislocated by deep-rooted faults. The study aimed at elucidating groundwater origin and circulation, using isotopic tracers (δ18O, δ2H, δ11B and 87Sr/86Sr) coupled to groundwater dating (Tritium, CFCs and SF6). Besides recharge by local precipitation over the Riardo hydrogeological basin, stable isotope ratios in water indicated an extra-basin recharge, likely from the elevated surrounding carbonate reliefs (e.g., Maggiore and Matese Mts.). The mineralization process, promoted by the deep CO2 flux, controls the B and Sr contents. However, their isotopic ratios did not allow discriminating between circulation in the volcanic and in the carbonate aquifers, as in the latter the isotopic composition differed from the original marine signature. Groundwater model ages ranged from ~ 30 years for the volcanic endmember to 〉 70 years for the deep, mineralized end-member, with longer circuits recharged at higher elevations. Overall, the results of this study were particularly relevant for mineral water exploitation. A recharge from outside the hydrogeological basin could be evidenced, especially for the more mineralized and valuable groundwater, and an active recent recharge was detected for the whole Riardo system. Both findings will contribute to the refinement of the hydrogeological model and water budget, and to a sustainable development of the resource.

Description: Published

Description: 1–28

Description: 6A. Geochimica per l'ambiente e geologia medica

Description: JCR Journal

Description: El Niño-Southern Oscillation (ENSO) is known to affect the Northern Hemisphere tropospheric circulation in late-winter (January–March), but whether El Niño and La Niña lead to symmetric impacts and with the same underlying dynamics remains unclear, particularly in the North Atlantic. Three state-of-the-art atmospheric models forced by symmetric anomalous sea surface temperature (SST) patterns, mimicking strong ENSO events, are used to robustly diagnose symmetries and asymmetries in the extra-tropical ENSO response. Asymmetries arise in the sea-level pressure (SLP) response over the North Pacific and North Atlantic, as the response to La Niña tends to be weaker and shifted westward with respect to that of El Niño. The difference in amplitude can be traced back to the distinct energy available for the two ENSO phases associated with the non-linear diabatic heating response to the total SST field. The longitudinal shift is embedded into the large-scale Rossby wave train triggered from the tropical Pacific, as its anomalies in the upper troposphere show a similar westward displacement in La Niña compared to El Niño. To fully explain this shift, the response in tropical convection and the related anomalous upper-level divergence have to be considered together with the climatological vorticity gradient of the subtropical jet, i.e. diagnosing the tropical Rossby wave source. In the North Atlantic, the ENSO-forced SLP signal is a well-known dipole between middle and high latitudes, different from the North Atlantic Oscillation, whose asymmetry is not indicative of distinct mechanisms driving the teleconnection for El Niño and La Niña.

Description: Published

Description: 1965–1986

Description: 4A. Oceanografia e clima

Description: JCR Journal

Description: The ionospheric equivalent slab thickness (τ ) is a parameter characterizing both the distribution of the plasma in the ionosphere and the shape of the corresponding vertical electron density profile. It is calculated as the ratio of the vertical total electron content (vTEC) to the ionospheric F2-layer electron density maximum (NmF2). Since its definition dated back in the 60s, a lot of information on the behavior of τ for different helio-geophysical conditions has been cumulated and the connection with several plasma properties has been also demonstrated. The beginning of the Global Positioning System (GPS) era in the 90s had a strong effect on the studies about τ because GPS signals allow to obtain the vTEC up to about 20000 km of altitude. Recently, τ has also found application in many data-assimilation methodologies, especially for the improvement of empirical ionospheric models based on near real-time data. All of these topics are reviewed and discussed in this paper based on the literature published in the last sixty years. Moreover, to highlight and summarize the main global climatological features of τ, in this work we selected thirty-two ionospheric stations globally distributed and co-located with ground-based Global Navigation Satellite System (GNSS) receivers, for the last two solar cycles. This allowed to collect a dataset of NmF2 and vTEC that represents the largest and most complete ever analyzed for studies concerning τ , which gave the chance to deeply investigate its spatial, diurnal, seasonal, and solar activity variations. The corresponding results are presented and discussed in the light of the existing literature.

Description: Published

Description: 37

Description: 2A. Fisica dell'alta atmosfera

Description: JCR Journal

Description: A theoretical pattern for Fe and As co-precipitation was tested directly in a groundwater natural system. Several monitoring wells were sampled to identify the different endmembers that govern the hydrodynamics of the Ferrarelle Groundwater System in the Riardo Plain (Southern Italy). In agreement with recent investigations, we found a mix of a deep and a shallow component in different proportions, resulting in a specific chemical composition of groundwater in each well depending on the percentages of each component. The shallow component was characterized by EC ~ 430 µS/cm, Eh ~ 300 mV, Fe ~ 0.06 µmol/L and As ~ 0.01-0.12 µmol/L, while the deep component was characterized by EC ~ 3400 µS/cm, Eh ~ 170 mV, Fe ~ 140 µmol/L and As ~ 0.59 µmol/L. A general attenuation of As and Fe concentration that was not due to a simple dilution effect was observed in the mixing process. The oxidation of Fe(II) to Fe(III) produces solid precipitates which adsorb As from solution and then co-precipitate. The reactions pattern of Fe(II) oxidation and As adsorption gave a linear function between [As] and [Fe], where the angular coefficient depends on the [O2]/[H+] ratio. Chemical data obtained from our samples showed a very good agreement with this theoretical relationship. The investigated geochemical dynamics represented a natural process of attenuation of Fe and As, two undesirable elements that usually affect groundwater quality in volcanic aquifers in central-southern Italy, which are exploited to supply drinking water.

Description: Published

Description: pages 2065–2082

Description: 6A. Geochimica per l'ambiente e geologia medica

Description: JCR Journal

Description: The predictability of the Northern Hemisphere stratosphere and its underlying dynamics are investigated in five state-of-the-art seasonal prediction systems from the Copernicus Climate Change Service (C3S) multi-model database. Special attention is devoted to the connection between the stratospheric polar vortex (SPV) and lower-stratosphere wave activity (LSWA). We find that in winter (December to February) dynamical forecasts initialised on the first of November are considerably more skilful than empirical forecasts based on October anomalies. Moreover, the coupling of the SPV with mid-latitude LSWA (i.e., meridional eddy heat flux) is generally well reproduced by the forecast systems, allowing for the identification of a robust link between the predictability of wave activity above the tropopause and the SPV skill. Our results highlight the importance of November-to-February LSWA, in particular in the Eurasian sector, for forecasts of the winter stratosphere. Finally, the role of potential sources of seasonal stratospheric predictability is considered: we find that the C3S multi-model overestimates the stratospheric response to El Niño–Southern Oscillation (ENSO) and underestimates the influence of the Quasi–Biennial Oscillation (QBO).

Description: Published

Description: 2109–2130

Description: 4A. Oceanografia e clima

Description: JCR Journal

Description: An integrated approach using chemical and microbial indicators has been tested in two different sites of the Campania Plain (Southern Italy) with different land use covering and different hydrogeological features in order: (1) to define the water-rock interaction processes, (2) to differentiate sources of pollution in a detailed way (3) to evaluate the degree of water quality in the studied alluvial aquifer and (4) to identify the most worrying elements for human's health. Groundwater have showed a HCO3-Ca signature for both investigated sites, and a progressive enrichment in alkali ions has been highlighted moving from the boundary of the plain toward the coastal areas, due to groundwater interaction with volcanic rocks along the flow path. The application of the Factor Analysis allowed to identify different sources of pollution, which were attributed to (a) leaks in the sewer system for the Agro-Aversano Area and also the spreading of manure as fertilizers in agricultural activities for the Caiazzo Plain. Furthermore, it has been highlighted that the use of major elements, trace elements and microbiological indicators, allows to accurately differentiate contamination processes in progress. In fact, from the results of the Factor Analysis applied in the Agro-Aversano area, no significant statistically relationships between major elements and microbiological indicators of fecal contamination were highlighted, unlike the Caiazzo plain where statistically significant correlations have been found between major and trace elements and microbiological indicators. The use of a Groundwater Quality Index has shown general poor water quality for the majority of analyzed samples due to the high amount of Nitrate and Fecal indicators. The use of a Health Risk Assessment highlighted that Nitrate coupled with Fluoride represent the most important concern for human health compared to the all investigated parameters in both sites.

Description: Published

Description: 2083–2099

Description: 6A. Geochimica per l'ambiente e geologia medica

Description: 7SR AMBIENTE – Servizi e ricerca per la società

Description: JCR Journal

Description: El Niño Southern Oscillation (ENSO) represents the major driver of interannual climate variability at global scale. Observational and model-based studies have fostered a long-standing debate on the shape and intensity of the ENSO influence over the Euro-Mediterranean sector. Indeed, the detection of this signal is strongly affected by the large internal variability that characterizes the atmospheric circulation in the North Atlantic–European (NAE) region. This study explores if and how the low-frequency variability of North Pacific sea surface temperature (SST) may impact the El Niño-NAE teleconnection in late winter, which consists of a dipolar pattern between middle and high latitudes. A set of idealized atmosphere-only experiments, prescribing different phases of the anomalous SST linked to the Pacific Decadal Oscillation (PDO) superimposed onto an El Niño-like forcing in the tropical Pacific, has been performed in a multi-model framework, in order to assess the potential modulation of the positive ENSO signal. The modelling results suggest, in agreement with observational estimates, that the PDO negative phase (PDO−) may enhance the amplitude of the El Niño-NAE teleconnection, while the dynamics involved appear to be unaltered. On the other hand, the modulating role of the PDO positive phase (PDO+) is not reliable across models. This finding is consistent with the atmospheric response to the PDO itself, which is robust and statistically significant only for PDO−. Its modulation seems to rely on the enhanced meridional SST gradient and the related turbulent heat-flux released along the Kuroshio–Oyashio extension. PDO− weakens the North Pacific jet, whereby favoring more poleward propagation of wave activity, strengthening the El Niño-forced Rossby wave-train. These results imply that there might be conditional predictability for the interannual Euro-Mediterranean climate variability depending on the background state.

Description: Published

Description: 2009–2029

Description: 4A. Oceanografia e clima

Description: JCR Journal

Description: Land surface and atmosphere are interlocked by the hydrological and energy cycles and the effects of soil water-air coupling can modulate near-surface temperatures. In this work, three paired experiments were designed to evaluate impacts of different soil moisture initial and boundary conditions on summer temperatures in the Mediterranean transitional climate regime region. In this area, evapotranspiration is not limited by solar radiation, rather by soil moisture, which therefore controls the boundary layer variability. Extremely dry, extremely wet and averagely humid ground conditions are imposed to two global climate models at the beginning of the warm and dry season. Then, sensitivity experiments, where atmosphere is alternatively interactive with and forced by land surface, are launched. The initial soil state largely affects summer near-surface temperatures: dry soils contribute to warm the lower atmosphere and exacerbate heat extremes, while wet terrains suppress thermal peaks, and both effects last for several months. Land-atmosphere coupling proves to be a fundamental ingredient to modulate the boundary layer state, through the partition between latent and sensible heat fluxes. In the coupled runs, early season heat waves are sustained by interactive dry soils, which respond to hot weather conditions with increased evaporative demand, resulting in longer-lasting extreme temperatures. On the other hand, when wet conditions are prescribed across the season, the occurrence of hot days is suppressed. The land surface prescribed by climatological precipitation forcing causes a temperature drop throughout the months, due to sustained evaporation of surface soil water. Results have implications for seasonal forecasts on both rain-fed and irrigated continental regions in transitional climate zones.

Description: Published

Description: 1943–1963

Description: 4A. Oceanografia e clima

Description: JCR Journal

Description: Geothermal areas of Greece are located in regions affected by recent volcanism and in continental basins characterised by elevated heat flow. Many of them are found along the coast and thus, water is often saline due to marine intrusion. In the current study, we present about 300 unpublished and literature data from thermal and cold mineral waters collected along Greece. Samples were analysed for major ions, Li, SiO2 and isotopes in water. Measured temperatures range from 6.5 to 98°C, pH from 1.96 to 11.98, whilst Total Dissolved Solutes (TDS) from 0.22 to 51 g/L. Waters were subdivided into four main groups: i) thermal; ii) cold; iii) acidic (pH 〈5) and iv) hyperalkaline (pH 〉11). On statistical basis, the thermal waters were subdivided into subgroups according to both their temperature [warm (〈29 °C), hypothermal (29-48 °C), thermal (48-75 °C) and hyperthermal (〉75 °C)] and TDS [low salinity (〈4 g/L), brackish (4-30 g/L) and saline (〉30 g/L)]. Cold waters were subdivided basing on their pCO2 [low (〈0.05 atm), medium (0.05-0.85 atm) and high (〉0.85 atm)]. δ18O-H2O ranges from -12.7 to +2.7 ‰ vs. SMOW, while δ2H-H2O from -91 to +12 ‰ vs. SMOW being generally comprised between the Global Meteoric Water Line and the East Mediterranean Meteoric Water Line. Positive δ18O shifts with respect to the former are mostly related to mixing with seawater, while only for a few samples they point to high-temperature water-rock interaction processes. Only a few thermal waters gave reliable geothermometric estimates, suggesting reservoir temperatures between 80 and 260 °C.

Description: Published

Description: 2111–2133

Description: 6A. Geochimica per l'ambiente e geologia medica

Description: JCR Journal

Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Huntley, N., Brandt, M., Becker, C., Miller, C., Meiling, S., Correa, A., Holstein, D., Muller, E., Mydlarz, L., Smith, T., & Apprill, A. Experimental transmission of Stony Coral Tissue Loss Disease results in differential microbial responses within coral mucus and tissue. ISME Communications, 2(1), (2022): 46, https://doi.org/10.1038/s43705-022-00126-3.

Description: Stony coral tissue loss disease (SCTLD) is a widespread and deadly disease that affects nearly half of Caribbean coral species. To understand the microbial community response to this disease, we performed a disease transmission experiment on US Virgin Island (USVI) corals, exposing six species of coral with varying susceptibility to SCTLD. The microbial community of the surface mucus and tissue layers were examined separately using a small subunit ribosomal RNA gene-based sequencing approach, and data were analyzed to identify microbial community shifts following disease acquisition, potential causative pathogens, as well as compare microbiota composition to field-based corals from the USVI and Florida outbreaks. While all species displayed similar microbiome composition with disease acquisition, microbiome similarity patterns differed by both species and mucus or tissue microhabitat. Further, disease exposed but not lesioned corals harbored a mucus microbial community similar to those showing disease signs, suggesting that mucus may serve as an early warning detection for the onset of SCTLD. Like other SCTLD studies in Florida, Rhodobacteraceae, Arcobacteraceae, Desulfovibrionaceae, Peptostreptococcaceae, Fusibacter, Marinifilaceae, and Vibrionaceae dominated diseased corals. This study demonstrates the differential response of the mucus and tissue microorganisms to SCTLD and suggests that mucus microorganisms may be diagnostic for early disease exposure.

Description: This work was funded by an International Coral Reef Society student grant to N.H., National Science Foundation (NSF) VI EPSCoR 0814417 and 1946412 and NSF (Biological Oceanography) award numbers 1928753 to MEB and TBS, 1928609 to AMSC, 1928817 to EMM, 19228771 to LDM, 1927277 to DMH as well as 1928761 and 1938112 to AA, NSF EEID award number 2109622 to MEB, AA, LDM, and AMSC, and a NOAA OAR Cooperative Institutes award to AA (#NA19OAR4320074). Samples were collected under permit #DFW19057U authorized by the Department of Planning and Natural Resources Coastal Zone Management.

Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Peredo, E. L., & Cardon, Z. G. Shared up-regulation and contrasting down-regulation of gene expression distinguish desiccation-tolerant from intolerant green algae. Proceedings of the National Academy of Sciences of the United States of America, 117(29), 1(2020): 7438-17445, doi:10.1073/pnas.1906904117.

Description: Among green plants, desiccation tolerance is common in seeds and spores but rare in leaves and other vegetative green tissues. Over the last two decades, genes have been identified whose expression is induced by desiccation in diverse, desiccation-tolerant (DT) taxa, including, e.g., late embryogenesis abundant proteins (LEA) and reactive oxygen species scavengers. This up-regulation is observed in DT resurrection plants, mosses, and green algae most closely related to these Embryophytes. Here we test whether this same suite of protective genes is up-regulated during desiccation in even more distantly related DT green algae, and, importantly, whether that up-regulation is unique to DT algae or also occurs in a desiccation-intolerant relative. We used three closely related aquatic and desert-derived green microalgae in the family Scenedesmaceae and capitalized on extraordinary desiccation tolerance in two of the species, contrasting with desiccation intolerance in the third. We found that during desiccation, all three species increased expression of common protective genes. The feature distinguishing gene expression in DT algae, however, was extensive down-regulation of gene expression associated with diverse metabolic processes during the desiccation time course, suggesting a switch from active growth to energy-saving metabolism. This widespread downshift did not occur in the desiccation-intolerant taxon. These results show that desiccation-induced up-regulation of expression of protective genes may be necessary but is not sufficient to confer desiccation tolerance. The data also suggest that desiccation tolerance may require induced protective mechanisms operating in concert with massive down-regulation of gene expression controlling numerous other aspects of metabolism.

Description: Dr. Louise Lewis (University of Connecticut) provided F. rotunda and A. deserticola. Suzanne Thomas and Jordan Stark provided expert technical assistance. This work was supported by the NSF, Division of Integrative Organismal Systems (1355085 to Z.G.C.), and an anonymous donor (to Z.G.C.).

Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Criswell, K. E., Roberts, L. E., Koo, E. T., Head, J. J., & Gillis, J. A. Hox gene expression predicts tetrapod-like axial regionalization in the skate, Leucoraja erinacea. Proceedings of the National Academy of Sciences of the United States of America, 118(51), (2021): e2114563118, https://doi.org/10.1073/pnas.2114563118.

Description: The axial skeleton of tetrapods is organized into distinct anteroposterior regions of the vertebral column (cervical, trunk, sacral, and caudal), and transitions between these regions are determined by colinear anterior expression boundaries of Hox5/6, -9, -10, and -11 paralogy group genes within embryonic paraxial mesoderm. Fishes, conversely, exhibit little in the way of discrete axial regionalization, and this has led to scenarios of an origin of Hox-mediated axial skeletal complexity with the evolutionary transition to land in tetrapods. Here, combining geometric morphometric analysis of vertebral column morphology with cell lineage tracing of hox gene expression boundaries in developing embryos, we recover evidence of at least five distinct regions in the vertebral skeleton of a cartilaginous fish, the little skate (Leucoraja erinacea). We find that skate embryos exhibit tetrapod-like anteroposterior nesting of hox gene expression in their paraxial mesoderm, and we show that anterior expression boundaries of hox5/6, hox9, hox10, and hox11 paralogy group genes predict regional transitions in the differentiated skate axial skeleton. Our findings suggest that hox-based axial skeletal regionalization did not originate with tetrapods but rather has a much deeper evolutionary history than was previously appreciated.

Description: This research was funded by a Natural Environment Research Council Grant (to J.J.H., J.A.G., and K.E.C.: NE/S000739/1) and a Royal Society University Research Fellowship (UF130182 and URF\R\191007), Royal Society Research Grant (RG140377), and University of Cambridge Sir Isaac Newton Trust Grant (14.23z) (to J.A.G.).

Description: © The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Northcutt, A. J., Kick, D. R., Otopalik, A. G., Goetz, B. M., Harris, R. M., Santin, J. M., Hofmann, H. A., Marder, E., & Schulz, D. J. Molecular profiling of single neurons of known identity in two ganglia from the crab Cancer borealis. Proceedings of the National Academy of Sciences of the United States of America, 116 (52) (2019): 26980-26990, doi: 10.1073/pnas.1911413116.

Description: Understanding circuit organization depends on identification of cell types. Recent advances in transcriptional profiling methods have enabled classification of cell types by their gene expression. While exceptionally powerful and high throughput, the ground-truth validation of these methods is difficult: If cell type is unknown, how does one assess whether a given analysis accurately captures neuronal identity? To shed light on the capabilities and limitations of solely using transcriptional profiling for cell-type classification, we performed 2 forms of transcriptional profiling—RNA-seq and quantitative RT-PCR, in single, unambiguously identified neurons from 2 small crustacean neuronal networks: The stomatogastric and cardiac ganglia. We then combined our knowledge of cell type with unbiased clustering analyses and supervised machine learning to determine how accurately functionally defined neuron types can be classified by expression profile alone. The results demonstrate that expression profile is able to capture neuronal identity most accurately when combined with multimodal information that allows for post hoc grouping, so analysis can proceed from a supervised perspective. Solely unsupervised clustering can lead to misidentification and an inability to distinguish between 2 or more cell types. Therefore, this study supports the general utility of cell identification by transcriptional profiling, but adds a caution: It is difficult or impossible to know under what conditions transcriptional profiling alone is capable of assigning cell identity. Only by combining multiple modalities of information such as physiology, morphology, or innervation target can neuronal identity be unambiguously determined.

Description: We thank members of the D.J.S., H.A.H., and E.M. laboratories for helpful discussions. We thank the Genomic Sequencing and Analysis Facility (The University of Texas [UT] at Austin) for library preparation and sequencing and the bioinformatics consulting team at the UT Austin Center for Computational Biology and Bioinformatics for helpful advice. This work was supported by National Institutes of Health grant R01MH046742-29 (to E.M. and D.J.S.) and the National Institute of General Medical Sciences T32GM008396 (support for A.J.N.) and National Institute of Mental Health grant 5R25MH059472-18 and the Grass Foundation (support for Neural Systems and Behavior Course at the Marine Biological Laboratory).

Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Lebrato, M., Garbe-Schönberg, D., Müller, M. N., Blanco-Ameijeiras, S., Feely, R. A., Lorenzoni, L., Molinero, J. C., Bremer, K., Jones, D. O. B., Iglesias-Rodriguez, D., Greeley, D., Lamare, M. D., Paulmier, A., Graco, M., Cartes, J., Barcelos E Ramos, J., de Lara, A., Sanchez-Leal, R., Jimenez, P., Paparazzo, F. E., Hartman, S. E., Westernströer, U., Küter, M., Benavides, R., da Silva, A. F., Bell, S., Payne, C., Olafsdottir, S., Robinson, K., Jantunen, L. M., Korablev, A., Webster, R. J., Jones, E. M., Gilg, O., Bailly du Bois, P., Beldowski, J., Ashjian, C., Yahia, N. D., Twining, B., Chen, X. G., Tseng, L. C., Hwang, J. S., Dahms, H. U., & Oschlies, A. Global variability in seawater Mg:Ca and Sr:Ca ratios in the modern ocean. Proceedings of the National Academy of Sciences of the United States of America, 117(36), (2020): 22281-22292, doi:10.1073/pnas.1918943117.

Description: Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth–ocean–atmosphere dynamic exchange of elements. The ratios’ dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previous data, to test the assumption of limited seawater Mg:Ca and Sr:Ca variability across marine environments globally. High variability was found in open-ocean upwelling and polar regions, shelves/neritic and river-influenced areas, where seawater Mg:Ca and Sr:Ca ratios range from ∼4.40 to 6.40 mmol:mol and ∼6.95 to 9.80 mmol:mol, respectively. Open-ocean seawater Mg:Ca is semiconservative (∼4.90 to 5.30 mol:mol), while Sr:Ca is more variable and nonconservative (∼7.70 to 8.80 mmol:mol); both ratios are nonconservative in coastal seas. Further, the Ca, Mg, and Sr elemental fluxes are connected to large total alkalinity deviations from International Association for the Physical Sciences of the Oceans (IAPSO) standard values. Because there is significant modern seawater Mg:Ca and Sr:Ca ratios variability across marine environments we cannot absolutely assume that fossil archives using taxa-specific proxies reflect true global seawater chemistry but rather taxa- and process-specific ecosystem variations, reflecting regional conditions. This variability could reconcile secular seawater Mg:Ca and Sr:Ca ratio reconstructions using different taxa and techniques by assuming an error of 1 to 1.50 mol:mol, and 1 to 1.90 mmol:mol, respectively. The modern ratios’ variability is similar to the reconstructed rise over 20 Ma (Neogene Period), nurturing the question of seminonconservative behavior of Ca, Mg, and Sr over modern Earth geological history with an overlooked environmental effect.

Description: We thank the researchers, staff, students, and volunteers in all the expeditions around the world for their contributions. One anonymous referee and Bernhard Peucker-Ehenbrink, Woods Hole Oceanographic Institution, contributed significantly to the final version of the manuscript. This study was developed under a grant from the Federal Ministry of Education and Research to D.G.-S. under contract 03F0722A, by the Kiel Cluster of Excellence “The Future Ocean” (D1067/87) to A.O. and M.L., and by the “European project on Ocean Acidification” (European Community’s Seventh Framework Programme FP7/2007-2013, grant agreement 211384) to A.O. and M.L. Additional funding was provided from project DOSMARES CTM2010-21810-C03-02, by the UK Natural Environment Research Council, to the National Oceanography Centre. This is Pacific Marine Environmental Laboratory contribution number 5046.

Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Chakraborty, A., Ruff, S. E., Dong, X., Ellefson, E. D., Li, C., Brooks, J. M., McBee, J., Bernard, B. B., & Hubert, C. R. J. Hydrocarbon seepage in the deep seabed links subsurface and seafloor biospheres. Proceedings of the National Academy of Sciences of the United States of America, 117(20), (2020): 11029-11037, doi: 10.1073/pnas.2002289117.

Description: Marine cold seeps transmit fluids between the subseafloor and seafloor biospheres through upward migration of hydrocarbons that originate in deep sediment layers. It remains unclear how geofluids influence the composition of the seabed microbiome and if they transport deep subsurface life up to the surface. Here we analyzed 172 marine surficial sediments from the deep-water Eastern Gulf of Mexico to assess whether hydrocarbon fluid migration is a mechanism for upward microbial dispersal. While 132 of these sediments contained migrated liquid hydrocarbons, evidence of continuous advective transport of thermogenic alkane gases was observed in 11 sediments. Gas seeps harbored distinct microbial communities featuring bacteria and archaea that are well-known inhabitants of deep biosphere sediments. Specifically, 25 distinct sequence variants within the uncultivated bacterial phyla Atribacteria and Aminicenantes and the archaeal order Thermoprofundales occurred in significantly greater relative sequence abundance along with well-known seep-colonizing members of the bacterial genus Sulfurovum, in the gas-positive sediments. Metabolic predictions guided by metagenome-assembled genomes suggested these organisms are anaerobic heterotrophs capable of nonrespiratory breakdown of organic matter, likely enabling them to inhabit energy-limited deep subseafloor ecosystems. These results point to petroleum geofluids as a vector for the advection-assisted upward dispersal of deep biosphere microbes from subsurface to surface environments, shaping the microbiome of cold seep sediments and providing a general mechanism for the maintenance of microbial diversity in the deep sea.

Description: We wish to thank Jody Sandel as well as the crew of R/V GeoExplorer for collection of piston cores, onboard core processing, sample preservation, and shipment. Cynthia Kwan and Oliver Horanszky are thanked for assistance with amplicon library preparation. We also wish to thank Jayne Rattray, Daniel Gittins, and Marc Strous for valuable discussions and suggestions, and Rhonda Clark for research support. Collaborations with Andy Mort from the Geological Survey of Canada, and Richard Hatton from Geoscience Wales are also gratefully acknowledged. This work was financially supported by a Mitacs Elevate Postdoctoral Fellowship awarded to A.C.; an Alberta Innovates-Technology Futures/Eyes High Postdoctoral Fellowship to S.E.R.; and a Natural Sciences and Engineering Research Council Strategic Project Grant, a Genome Canada Genomics Applications Partnership Program grant, a Canada Foundation for Innovation grant (CFI-JELF 33752) for instrumentation, and Campus Alberta Innovates Program Chair funding to C.R.J.H.

Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in MBL Hernandez, C. M., van Daalen, S. F., Caswell, H., Neubert, M. G., & Gribble, K. E. A demographic and evolutionary analysis of maternal effect senescence. Proceedings of the National Academy of Sciences of the United States of America, 17(28), (2020):16431-16437, doi: 10.1073/pnas.1919988117.

Description: Maternal effect senescence—a decline in offspring survival or fertility with maternal age—has been demonstrated in many taxa, including humans. Despite decades of phenotypic studies, questions remain about how maternal effect senescence impacts evolutionary fitness. To understand the influence of maternal effect senescence on population dynamics, fitness, and selection, we developed matrix population models in which individuals are jointly classified by age and maternal age. We fit these models to data from individual-based culture experiments on the aquatic invertebrate, Brachionus manjavacas (Rotifera). By comparing models with and without maternal effects, we found that maternal effect senescence significantly reduces fitness for B. manjavacas and that this decrease arises primarily through reduced fertility, particularly at maternal ages corresponding to peak reproductive output. We also used the models to estimate selection gradients, which measure the strength of selection, in both high growth rate (laboratory) and two simulated low growth rate environments. In all environments, selection gradients on survival and fertility decrease with increasing age. They also decrease with increasing maternal age for late maternal ages, implying that maternal effect senescence can evolve through the same process as in Hamilton’s theory of the evolution of age-related senescence. The models we developed are widely applicable to evaluate the fitness consequences of maternal effect senescence across species with diverse aging and fertility schedule phenotypes.

Description: K.E.G. was supported by Grant 5K01AG049049 from the National Institute on Aging and by the Bay and Paul Foundations. H.C. and S.F.v.D. were supported by the European Research Council through Advanced Grants 322829 and 788195 and by the Dutch Research Council through Grant ALWOP.2015.100. C.M.H. was supported by a National Science Foundation Graduate Research Fellowship. M.G.N. received funding from The Paul MacDonald Fye Chair for Excellence in Oceanography at the Woods Hole Oceanographic Institution.

Description: Author Posting. © National Academy of Sciences, 2021. This article is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of America 118(11), (2021): e2020025118, https://doi.org/10.1073/pnas.2020025118.

Description: For organisms to have robust locomotion, their neuromuscular organization must adapt to constantly changing environments. In jellyfish, swimming robustness emerges when marginal pacemakers fire action potentials throughout the bell’s motor nerve net, which signals the musculature to contract. The speed of the muscle activation wave is dictated by the passage times of the action potentials. However, passive elastic material properties also influence the emergent kinematics, with time scales independent of neuromuscular organization. In this multimodal study, we examine the interplay between these two time scales during turning. A three-dimensional computational fluid–structure interaction model of a jellyfish was developed to determine the resulting emergent kinematics, using bidirectional muscular activation waves to actuate the bell rim. Activation wave speeds near the material wave speed yielded successful turns, with a 76-fold difference in turning rate between the best and worst performers. Hyperextension of the margin occurred only at activation wave speeds near the material wave speed, suggesting resonance. This hyperextension resulted in a 34-fold asymmetry in the circulation of the vortex ring between the inside and outside of the turn. Experimental recording of the activation speed confirmed that jellyfish actuate within this range, and flow visualization using particle image velocimetry validated the corresponding fluid dynamics of the numerical model. This suggests that neuromechanical wave resonance plays an important role in the robustness of an organism’s locomotory system and presents an undiscovered constraint on the evolution of flexible organisms. Understanding these dynamics is essential for developing actuators in soft body robotics and bioengineered pumps.

Description: This research was funded by the NSF Division of Mathematical Sciences, under Faculty Early Career Development Program Grant 1151478 (to L.A.M.).

Description: 2021-09-16

Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kanso, E. A., Lopes, R. M., Strickler, J. R., Dabiri, J. O., & Costello, J. H. Teamwork in the viscous oceanic microscale. Proceedings of the National Academy of Sciences of the United States of America, 118(29), (2021): e2018193118, https://doi.org/10.1073/pnas.2018193118.

Description: Nutrient acquisition is crucial for oceanic microbes, and competitive solutions to solve this challenge have evolved among a range of unicellular protists. However, solitary solutions are not the only approach found in natural populations. A diverse array of oceanic protists form temporary or even long-lasting attachments to other protists and marine aggregates. Do these planktonic consortia provide benefits to their members? Here, we use empirical and modeling approaches to evaluate whether the relationship between a large centric diatom, Coscinodiscus wailesii, and a ciliate epibiont, Pseudovorticella coscinodisci, provides nutrient flux benefits to the host diatom. We find that fluid flows generated by ciliary beating can increase nutrient flux to a diatom cell surface four to 10 times that of a still cell without ciliate epibionts. This cosmopolitan species of diatom does not form consortia in all environments but frequently joins such consortia in nutrient-depleted waters. Our results demonstrate that symbiotic consortia provide a cooperative alternative of comparable or greater magnitude to sinking for enhancement of nutrient acquisition in challenging environments.

Description: We are grateful to Y. Garcia for help with organism sampling and sorting. E.A.K. is funded by NSF-2100209, NSF RAISE IOS-2034043 and NIH R01 HL 153622-01A1. R.M.L. is a CNPq research fellow (grant # 310642/2017-5). J.H.C. and J.O.D. are funded by Grant NSF-2100705.

Description: Author Posting. © National Academy of Sciences, 2020. This article is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of America 117(22), (2020): 12215-12221, doi: 10.1073/pnas.1918439117.

Description: Picophytoplankton are the most abundant primary producers in the ocean. Knowledge of their community dynamics is key to understanding their role in marine food webs and global biogeochemical cycles. To this end, we analyzed a 16-y time series of observations of a phytoplankton community at a nearshore site on the Northeast US Shelf. We used a size-structured population model to estimate in situ division rates for the picoeukaryote assemblage and compared the dynamics with those of the picocyanobacteria Synechococcus at the same location. We found that the picoeukaryotes divide at roughly twice the rate of the more abundant Synechococcus and are subject to greater loss rates (likely from viral lysis and zooplankton grazing). We describe the dynamics of these groups across short and long timescales and conclude that, despite their taxonomic differences, their populations respond similarly to changes in the biotic and abiotic environment. Both groups appear to be temperature limited in the spring and light limited in the fall and to experience greater mortality during the day than at night. Compared with Synechococcus, the picoeukaryotes are subject to greater top-down control and contribute more to the region’s primary productivity than their standing stocks suggest.

Description: We thank E. T. Crockford, E. E. Peacock, J. Fredericks, Z. Sandwith, the MVCO Operations Team, and divers of the Woods Hole Oceanographic Institution diving program. This work was supported by NSF Grants OCE-0119915 (to R.J.O. and H.M.S.) and OCE-1655686 (to M.G.N., R.J.O., A.R.S., and H.M.O.); NASA Grants NNX11AF07G (to H.M.S.) and NNX13AC98G (to H.M.S.); Gordon and Betty Moore Foundation Grant GGA#934 (to H.M.S.); and Simons Foundation Grant 561126 (to H.M.S.).

Description: 2020-11-15

Description: © The Author(s), 202. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in McDermott, J. M., Sylva, S. P., Ono, S., German, C. R., & Seewald, J. S. Abiotic redox reactions in hydrothermal mixing zones: decreased energy availability for the subsurface biosphere. Proceedings of the National Academy of Sciences of the United States of America, 117(34), (2020): 20453-20461, doi:10.1073/pnas.2003108117.

Description: Subseafloor mixing of high-temperature hot-spring fluids with cold seawater creates intermediate-temperature diffuse fluids that are replete with potential chemical energy. This energy can be harnessed by a chemosynthetic biosphere that permeates hydrothermal regions on Earth. Shifts in the abundance of redox-reactive species in diffuse fluids are often interpreted to reflect the direct influence of subseafloor microbial activity on fluid geochemical budgets. Here, we examine hydrothermal fluids venting at 44 to 149 °C at the Piccard hydrothermal field that span the canonical 122 °C limit to life, and thus provide a rare opportunity to study the transition between habitable and uninhabitable environments. In contrast with previous studies, we show that hydrocarbons are contributed by biomass pyrolysis, while abiotic sulfate (SO42−) reduction produces large depletions in H2. The latter process consumes energy that could otherwise support key metabolic strategies employed by the subseafloor biosphere. Available Gibbs free energy is reduced by 71 to 86% across the habitable temperature range for both hydrogenotrophic SO42− reduction to hydrogen sulfide (H2S) and carbon dioxide (CO2) reduction to methane (CH4). The abiotic H2 sink we identify has implications for the productivity of subseafloor microbial ecosystems and is an important process to consider within models of H2 production and consumption in young oceanic crust.

Description: Financial support was provided by the National Aeronautics and Space Administration (NASA) Astrobiology program (Awards NNX09AB75G and 80NSSC19K1427 to C.R.G. and J.S.S.) and the NSF (Award OCE-1061863 to C.R.G. and J.S.S.). Ship and vehicle time for cruise FK008 was provided by the Schmidt Ocean Institute. We thank the ROV Jason II and HROV Nereus groups, and the captain, officers, and crew of R/V Atlantis (AT18-16) and R/V Falkor (FK008) for their dedication to skillful operations at sea. We thank our scientific colleagues from both cruises, as well as Meg Tivey, Frieder Klein, and Scott Wankel for insightful discussions. We are grateful to the editor and two anonymous reviewers for providing helpful comments and suggestions.

Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Reysenbach, A. L., St John, E., Meneghin, J., Flores, G. E., Podar, M., Dombrowski, N., Spang, A., L'Haridon, S., Humphris, S. E., de Ronde, C. E. J., Caratori Tontini, F., Tivey, M., Stucker, V. K., Stewart, L. C., Diehl, A., & Bach, W. Complex subsurface hydrothermal fluid mixing at a submarine arc volcano supports distinct and highly diverse microbial communities. Proceedings of the National Academy of Sciences of the United States of America, 117(51), (2020): 202019021, doi:10.1073/pnas.2019021117.

Description: Hydrothermally active submarine volcanoes are mineral-rich biological oases contributing significantly to chemical fluxes in the deep sea, yet little is known about the microbial communities inhabiting these systems. Here we investigate the diversity of microbial life in hydrothermal deposits and their metagenomics-inferred physiology in light of the geological history and resulting hydrothermal fluid paths in the subsurface of Brothers submarine volcano north of New Zealand on the southern Kermadec arc. From metagenome-assembled genomes we identified over 90 putative bacterial and archaeal genomic families and nearly 300 previously unknown genera, many potentially endemic to this submarine volcanic environment. While magmatically influenced hydrothermal systems on the volcanic resurgent cones of Brothers volcano harbor communities of thermoacidophiles and diverse members of the superphylum “DPANN,” two distinct communities are associated with the caldera wall, likely shaped by two different types of hydrothermal circulation. The communities whose phylogenetic diversity primarily aligns with that of the cone sites and magmatically influenced hydrothermal systems elsewhere are characterized predominately by anaerobic metabolisms. These populations are probably maintained by fluids with greater magmatic inputs that have interacted with different (deeper) previously altered mineral assemblages. However, proximal (a few meters distant) communities with gene-inferred aerobic, microaerophilic, and anaerobic metabolisms are likely supported by shallower seawater-dominated circulation. Furthermore, mixing of fluids from these two distinct hydrothermal circulation systems may have an underlying imprint on the high microbial phylogenomic diversity. Collectively our results highlight the importance of considering geologic evolution and history of subsurface processes in studying microbial colonization and community dynamics in volcanic environments.

Description: We thank the captain and crew of the R/V Thompson and the engineers from Woods Hole Oceanographic Institution for the successful operation of ROV Jason. The project was funded by NSF grants OCE‐1558356 (Principal Investigator S.E.H.) and OCE-1558795 (Principal Investigator A.-L.R.). S.L. received a grant from the University of Brest to work in the A.-L.R. laboratory. A travel fund from Interridge enabled A.D. to participate on the R/V Thompson cruise. Funding for this work for C.E.J.d.R., F.C.T., V.K.S., and L.C.S. was provided by the New Zealand government. A.S. was supported by the Swedish Research Council (Vetenskapsrådet starting grant 2016-03559 to A.S.) and the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (Dutch Research Council) Foundation of the Netherlands Organization for Scientific Research (Women In Science Excel [WISE] fellowship to A.S.). A.-L.R. and E.S.J. thank Rika Anderson for helpful methodological discussions and Sean Sylva for assistance in shipboard geochemical analysis.

Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Coesel, S. N., Durham, B. P., Groussman, R. D., Hu, S. K., Caron, D. A., Morales, R. L., Ribalet, F., & Armbrust, E. V. Diel transcriptional oscillations of light-sensitive regulatory elements in open-ocean eukaryotic plankton communities. Proceedings of the National Academy of Sciences of the United States of America, 118(6), (2021): e2011038118, https://doi.org/10.1073./pnas.2011038118.

Description: The 24-h cycle of light and darkness governs daily rhythms of complex behaviors across all domains of life. Intracellular photoreceptors sense specific wavelengths of light that can reset the internal circadian clock and/or elicit distinct phenotypic responses. In the surface ocean, microbial communities additionally modulate nonrhythmic changes in light quality and quantity as they are mixed to different depths. Here, we show that eukaryotic plankton in the North Pacific Subtropical Gyre transcribe genes encoding light-sensitive proteins that may serve as light-activated transcription factors, elicit light-driven electrical/chemical cascades, or initiate secondary messenger-signaling cascades. Overall, the protistan community relies on blue light-sensitive photoreceptors of the cryptochrome/photolyase family, and proteins containing the Light-Oxygen-Voltage (LOV) domain. The greatest diversification occurred within Haptophyta and photosynthetic stramenopiles where the LOV domain was combined with different DNA-binding domains and secondary signal-transduction motifs. Flagellated protists utilize green-light sensory rhodopsins and blue-light helmchromes, potentially underlying phototactic/photophobic and other behaviors toward specific wavelengths of light. Photoreceptors such as phytochromes appear to play minor roles in the North Pacific Subtropical Gyre. Transcript abundance of environmental light-sensitive protein-encoding genes that display diel patterns are found to primarily peak at dawn. The exceptions are the LOV-domain transcription factors with peaks in transcript abundances at different times and putative phototaxis photoreceptors transcribed throughout the day. Together, these data illustrate the diversity of light-sensitive proteins that may allow disparate groups of protists to respond to light and potentially synchronize patterns of growth, division, and mortality within the dynamic ocean environment.

Description: This work was supported by a grant from the Simons Foundation (SCOPE Award 329108 [to E.V.A.]) and XSEDE Grant Allocation OCE160019 (to R.D.G.).

Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Dommain, R., Riedl, S., Olaka, L. A., deMenocal, P., Deino, A. L., Owen, R. B., Muiruri, V., Müller, J., Potts, R., & Strecker, M. R. Holocene bidirectional river system along the Kenya Rift and its influence on East African faunal exchange and diversity gradients. Proceedings of the National Academy of Sciences of the United States of America, 119(28),(2022): e2121388119, https://doi.org/10.1073/pnas.2121388119.

Description: East Africa is a global biodiversity hotspot and exhibits distinct longitudinal diversity gradients from west to east in freshwater fishes and forest mammals. The assembly of this exceptional biodiversity and the drivers behind diversity gradients remain poorly understood, with diversification often studied at local scales and less attention paid to biotic exchange between Afrotropical regions. Here, we reconstruct a river system that existed for several millennia along the now semiarid Kenya Rift Valley during the humid early Holocene and show how this river system influenced postglacial dispersal of fishes and mammals due to its dual role as a dispersal corridor and barrier. Using geomorphological, geochronological, isotopic, and fossil analyses and a synthesis of radiocarbon dates, we find that the overflow of Kenyan rift lakes between 12 and 8 ka before present formed a bidirectional river system consisting of a “Northern River” connected to the Nile Basin and a “Southern River,” a closed basin. The drainage divide between these rivers represented the only viable terrestrial dispersal corridor across the rift. The degree and duration of past hydrological connectivity between adjacent river basins determined spatial diversity gradients for East African fishes. Our reconstruction explains the isolated distribution of Nilotic fish species in modern Kenyan rift lakes, Guineo-Congolian mammal species in forests east of the Kenya Rift, and recent incipient vertebrate speciation and local endemism in this region. Climate-driven rearrangements of drainage networks unrelated to tectonic activity contributed significantly to the assembly of species diversity and modern faunas in the East African biodiversity hotspot.

Description: R.D. was funded by a Smithsonian Human Origins Postdoctoral Fellowship and by Geo.X—the Research Network for Geosciences in Berlin and Potsdam. Fig. 1 D, E, and G and SI Appendix, Figs. S1 and S3 are based on the TanDEM-X Science DEM granted to L.A.O. and S.R. by the German Aerospace Center (DLR) in 2017. L.A.O. acknowledges the Volkswagen Foundation for funding this study with Grant No. 89369. M.R.S. and S.R. were supported by funds from Potsdam University and the Geothermal Development Company of Kenya, and R.B.O. and V.M. were supported by the Hong Kong General Research Fund. We acknowledge support from the National Museums of Kenya and the Kenya Government permission granted by the Ministry of Sports, Culture and the Arts, and by the National Commission for Science, Technology and Innovation (NACOSTI) Permits P/14/7709/683 (to R.P.) and P/16/11924/11448 (to L.A.O.). This work is a contribution of the Olorgesailie Drilling Project, for which support from the National Museums of Kenya, the Oldonyo Nyokie Group Ranch, the Peter Buck Fund for Human Origins Research (Smithsonian Institution), the William H. Donner Foundation, the Ruth and Vernon Taylor Foundation, Whitney and Betty MacMillan, and the Smithsonian Human Origins Program is gratefully acknowledged. LacCore is acknowledged for support in drilling and core storage.

Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Bell, T. W., & Siegel, D. A. Nutrient availability and senescence spatially structure the dynamics of a foundation species. Proceedings of the National Academy of Sciences of the United States of America, 119(1), (2021): e2105135118, https://doi.org/10.1073/pnas.2105135118.

Description: Disentangling the roles of the external environment and internal biotic drivers of plant population dynamics is challenging due to the absence of relevant physiological and abundance information over appropriate space and time scales. Remote observations of giant kelp biomass and photosynthetic pigment concentrations are used to show that spatiotemporal patterns of physiological condition, and thus growth and production, are regulated by different processes depending on the scale of observation. Nutrient supply was linked to regional scale (〉1 km) physiological condition dynamics, and kelp forest stands were more persistent where nutrient levels were consistently high. However, on local scales (〈1 km), internal senescence processes related to canopy age demographics determined patterns of biomass loss across individual kelp forests despite uniform nutrient conditions. Repeat measurements of physiology over continuous spatial fields can provide insights into complex dynamics that are unexplained by the environmental drivers thought to regulate abundance. Emerging remote sensing technologies that provide simultaneous estimates of abundance and physiology can quantify the roles of environmental change and demographics governing plant population dynamics for a wide range of aquatic and terrestrial ecosystems.

Description: This work was supported by the US NSF (Grants OCE 1232779 and 1831937), by the US Department of Energy (Cooperative Agreement DE-AR0000922), and by NASA (Grant NNX14AR62A) and the NASA Earth and Space Sciences Fellowship program in support of T.W.B.

Description: Author Posting. © National Academy of Sciences, 2020. This article is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences (2020): 201913625, doi: 10.1073/pnas.1913625117.

Description: Oceanic transform faults display a unique combination of seismic and aseismic slip behavior, including a large globally averaged seismic deficit, and the local occurrence of repeating magnitude (M) ∼6 earthquakes with abundant foreshocks and seismic swarms, as on the Gofar transform of the East Pacific Rise and the Blanco Ridge in the northeast Pacific Ocean. However, the underlying mechanisms that govern the partitioning between seismic and aseismic slip and their interaction remain unclear. Here we present a numerical modeling study of earthquake sequences and aseismic transient slip on oceanic transform faults. In the model, strong dilatancy strengthening, supported by seismic imaging that indicates enhanced fluid-filled porosity and possible hydrothermal circulation down to the brittle–ductile transition, effectively stabilizes along-strike seismic rupture propagation and results in rupture barriers where aseismic transients arise episodically. The modeled slow slip migrates along the barrier zones at speeds ∼10 to 600 m/h, spatiotemporally correlated with the observed migration of seismic swarms on the Gofar transform. Our model thus suggests the possible prevalence of episodic aseismic transients in M ∼6 rupture barrier zones that host active swarms on oceanic transform faults and provides candidates for future seafloor geodesy experiments to verify the relation between aseismic fault slip, earthquake swarms, and fault zone hydromechanical properties.

Description: We thank Joan Gomberg, Ruth Harris, Steve Hickman, Shane Detweiler, Mike Diggles, and two anonymous external reviewers for their thoughtful comments that helped to improve the manuscript. This study was supported by Natural Sciences and Engineering Research Council of Canada Discovery Grants RGPIN/418338-2012 and RGPIN-2018-05389; and NSF Grants OCE-10-61203 and OCE-18-33279.

Description: 2020-10-28

Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Buesseler, K. O., Boyd, P. W., Black, E. E., & Siegel, D. A. Metrics that matter for assessing the ocean biological carbon pump. Proceedings of the National Academy of Sciences of the United States of America, (2020): 201918114, doi: 10.1073/pnas.1918114117.

Description: The biological carbon pump (BCP) comprises wide-ranging processes that set carbon supply, consumption, and storage in the oceans’ interior. It is becoming increasingly evident that small changes in the efficiency of the BCP can significantly alter ocean carbon sequestration and, thus, atmospheric CO2 and climate, as well as the functioning of midwater ecosystems. Earth system models, including those used by the United Nation’s Intergovernmental Panel on Climate Change, most often assess POC (particulate organic carbon) flux into the ocean interior at a fixed reference depth. The extrapolation of these fluxes to other depths, which defines the BCP efficiencies, is often executed using an idealized and empirically based flux-vs.-depth relationship, often referred to as the “Martin curve.” We use a new compilation of POC fluxes in the upper ocean to reveal very different patterns in BCP efficiencies depending upon whether the fluxes are assessed at a fixed reference depth or relative to the depth of the sunlit euphotic zone (Ez). We find that the fixed-depth approach underestimates BCP efficiencies when the Ez is shallow, and vice versa. This adjustment alters regional assessments of BCP efficiencies as well as global carbon budgets and the interpretation of prior BCP studies. With several international studies recently underway to study the ocean BCP, there are new and unique opportunities to improve our understanding of the mechanistic controls on BCP efficiencies. However, we will only be able to compare results between studies if we use a common set of Ez-based metrics.

Description: We thank the many scientists whose ideas and contributions over the years are the foundation of this paper. This includes A. Martin, who led the organization of the BIARRITZ group (now JETZON) workshop in July 2019, discussions at which helped to motivate this article. We thank D. Karl for pointing us in the right direction for this paper format at PNAS and two thoughtful reviewers who through their comments helped to improve this manuscript. Support for writing this piece is acknowledged from several sources, including the Woods Hole Oceanographic Institution’s Ocean Twilight Zone project (K.O.B.); NASA as part of the EXport Processes in the global Ocean from RemoTe Sensing (EXPORTS) program (K.O.B. and D.A.S.). E.E.B. was supported by a postdoctoral fellowship through the Ocean Frontier Institute at Dalhousie University. P.W.B. was supported by the Australian Research Council through a Laureate (FL160100131).

Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Anderson, D. M., Fachon, E., Pickart, R. S., Lin, P., Fischer, A. D., Richlen, M. L., Uva, V., Brosnahan, M. L., McRaven, L., Bahr, F., Lefebvre, K., Grebmeier, J. M., Danielson, S. L., Lyu, Y., & Fukai, Y. Evidence for massive and recurrent toxic blooms of Alexandrium catenella in the Alaskan Arctic. Proceedings of the National Academy of Sciences of the United States of America, 118(41) (2021): e2107387118, https://doi.org/10.1073/pnas.2107387118.

Description: Among the organisms that spread into and flourish in Arctic waters with rising temperatures and sea ice loss are toxic algae, a group of harmful algal bloom species that produce potent biotoxins. Alexandrium catenella, a cyst-forming dinoflagellate that causes paralytic shellfish poisoning worldwide, has been a significant threat to human health in southeastern Alaska for centuries. It is known to be transported into Arctic regions in waters transiting northward through the Bering Strait, yet there is little recognition of this organism as a human health concern north of the Strait. Here, we describe an exceptionally large A. catenella benthic cyst bed and hydrographic conditions across the Chukchi Sea that support germination and development of recurrent, locally originating and self-seeding blooms. Two prominent cyst accumulation zones result from deposition promoted by weak circulation. Cyst concentrations are among the highest reported globally for this species, and the cyst bed is at least 6× larger in area than any other. These extraordinary accumulations are attributed to repeated inputs from advected southern blooms and to localized cyst formation and deposition. Over the past two decades, warming has likely increased the magnitude of the germination flux twofold and advanced the timing of cell inoculation into the euphotic zone by 20 d. Conditions are also now favorable for bloom development in surface waters. The region is poised to support annually recurrent A. catenella blooms that are massive in scale, posing a significant and worrisome threat to public and ecosystem health in Alaskan Arctic communities where economies are subsistence based.

Description: Funding for D.M.A., R.S.P., E.F., P.L., A.D.F., V.U., M.L.B., L.M., F.B., and M.L.R. was provided by grants from the NSF Office of Polar Programs (Grants OPP-1823002 and OPP-1733564) and the National Ocanic and Atmospheric Administration (NOAA) Arctic Research program (through the Cooperative Institute for the North Atlantic Region [CINAR; Grants NA14OAR4320158 and NA19OAR4320074]), for J.M.G. through CINAR 22309.07 UMCES (University of Maryland Center for Environmental Science), and for D.M.A. and K.L. through NOAA’s Center for Coastal and Ocean Studies Ecology and Oceanography of Harmful Algal Blooms (ECOHAB) Program (NA20NOS4780195). Funding for D.M.A., M.L.R., M.L.B., E.F., V.U., and A.D.F. was also provided by NSF (Grant OCE-1840381) and NIH (Grant 1P01-ES028938-01) through the Woods Hole Center for Oceans and Human Health. S.L.D. was supported by North Pacific Research Board IERP Grants A91-99a and A91-00a. This is IERP publication ArcticIERP-41 and ECOHAB Contribution No. ECO983.

Description: Author Posting. © National Academy of Sciences, 2021. This article is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of America 118(8), (2021): e1918605118, https://doi.org/10.1073/pnas.1918605118.

Description: Changes in chromium (Cr) isotope ratios due to fractionation between trivalent [Cr(III)] and hexavalent [Cr(VI)] are being utilized by geologists to infer oxygen conditions in past environments. However, there is little information available on Cr in the modern ocean to ground-truth these inferences. Transformations between the two chromium species are important processes in oceanic Cr cycling. Here we present profiles of hexavalent and trivalent Cr concentrations and stable isotope ratios from the eastern tropical North Pacific (ETNP) oxygen-deficient zone (ODZ) which support theoretical and experimental studies that predict that lighter Cr is preferentially reduced in low-oxygen environments and that residual dissolved Cr becomes heavier due to removal of particle-reactive Cr(III) on sinking particles. The Cr(III) maximum dominantly occurs in the upper portion of the ODZ, implying that microbial activity (dependent on the sinking flux of organic matter) may be the dominant mechanism for this transformation, rather than a simple inorganic chemical conversion between the species depending on the redox potential.

Description: We thank chief scientist Gabrielle Rocap for accommodating us on cruises Roger Revelle 1804-5 and Kilo Moana 19-20 (sponsored by NSF Grant DEB-1542240 to G. Rocap, A. Devol, R. Kiel, and C. Deutch), Jim Moffett for helping with sampling on these cruises, and Mark Altabet and Frank Stewart for collecting the samples from station 2T on cruise New Horizon 1410. This research was supported by NSF Grant OCE-1736996 (to E.A.B.) and by a fellowship from the Massachusetts Institute of Technology/Woods Hole Oceanographic Institution Joint Program in Oceanography.

Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Bucklin, A., Peijnenburg, K. T. C. A., Kosobokova, K. N., O'Brien, T. D., Blanco-Bercial, L., Cornils, A., Falkenhaug, T., Hopcroft, R. R., Hosia, A., Laakmann, S., Li, C., Martell, L., Questel, J. M., Wall-Palmer, D., Wang, M., Wiebe, P. H., & Weydmann-Zwolicka, A. Toward a global reference database of COI barcodes for marine zooplankton. Marine Biology, 168(6), (2021): 78, https://doi.org/10.1007/s00227-021-03887-y.

Description: Characterization of species diversity of zooplankton is key to understanding, assessing, and predicting the function and future of pelagic ecosystems throughout the global ocean. The marine zooplankton assemblage, including only metazoans, is highly diverse and taxonomically complex, with an estimated ~28,000 species of 41 major taxonomic groups. This review provides a comprehensive summary of DNA sequences for the barcode region of mitochondrial cytochrome oxidase I (COI) for identified specimens. The foundation of this summary is the MetaZooGene Barcode Atlas and Database (MZGdb), a new open-access data and metadata portal that is linked to NCBI GenBank and BOLD data repositories. The MZGdb provides enhanced quality control and tools for assembling COI reference sequence databases that are specific to selected taxonomic groups and/or ocean regions, with associated metadata (e.g., collection georeferencing, verification of species identification, molecular protocols), and tools for statistical analysis, mapping, and visualization. To date, over 150,000 COI sequences for ~ 5600 described species of marine metazoan plankton (including holo- and meroplankton) are available via the MZGdb portal. This review uses the MZGdb as a resource for summaries of COI barcode data and metadata for important taxonomic groups of marine zooplankton and selected regions, including the North Atlantic, Arctic, North Pacific, and Southern Oceans. The MZGdb is designed to provide a foundation for analysis of species diversity of marine zooplankton based on DNA barcoding and metabarcoding for assessment of marine ecosystems and rapid detection of the impacts of climate change.

Description: Funding sources for authors of the review paper are described here: Scientific Committee on Oceanic Research (SCOR), and a grant to SCOR from the U.S. National Science Foundation (OCE-1840868). Netherlands Organization for Scientific Research (NWO) Vidi Grant/Award Number: 016.161.351 to K.T.C.A.P. European Union Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 746186 (POSEIDoN) to D.W.P. The work of K.N.K. was performed in the framework of the state assignment of IO RAS (Theme No. 0128-2021-0007) and partially supported by Russian Foundation for Basic Research grants No. 18-05-60158 and No. 19-04-00955. The work of A.W.Z. was supported by a grant from HIDEA—Hidden diversity of the Arctic Ocean (No. 2017/27/B/NZ8/01056) from the National Science Centre, Poland, and a Fulbright Senior Award. The Norwegian Taxonomy Initiative of the Norwegian Biodiversity Information Centre provided funding for A.H. and L.M. (Project Nos. 70184233/HYPNO and 70184240/NORHYDRO), and for T.F. (Project Nos. 70184233/COPCLAD and 70184241/HYPCOP). The work of R.R.H. and J.M.Q. was supported by Census of Marine Life and NOAA Ocean Exploration and Research (NA05OAR4601079 and NA15OAR0110209). The work of S.L. was conducted at the Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB). HIFMB is a collaboration between the Alfred-Wegener-Institute, Helmholtz-Center for Polar and Marine Research, and the Carl-von-Ossietzky University Oldenburg, initially funded by the Ministry for Science and Culture of Lower Saxony and the Volkswagen Foundation through the Niedersächsisches Vorab’ grant program (Grant No. ZN3285).

Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Schaafsma, F. L., David, C. L., Kohlbach, D., Ehrlich, J., Castellani, G., Lange, B. A., Vortkamp, M., Meijboom, A., Fortuna-Wunsch, A., Immerz, A., Cantzler, H., Klasmeier, A., Zakharova, N., Schmidt, K., Van de Putte, A. P., van Franeker, J. A., & Flores, H. Allometric relationships of ecologically important Antarctic and Arctic zooplankton and fish species. Polar Biology 45, (2022): 203–224, https://doi.org/10.1007/s00300-021-02984-4.

Description: Allometric relationships between body properties of animals are useful for a wide variety of purposes, such as estimation of biomass, growth, population structure, bioenergetic modelling and carbon flux studies. This study summarizes allometric relationships of zooplankton and nekton species that play major roles in polar marine food webs. Measurements were performed on 639 individuals of 15 species sampled during three expeditions in the Southern Ocean (winter and summer) and 2374 individuals of 14 species sampled during three expeditions in the Arctic Ocean (spring and summer). The information provided by this study fills current knowledge gaps on relationships between length and wet/dry mass of understudied animals, such as various gelatinous zooplankton, and of animals from understudied seasons and maturity stages, for example, for the krill Thysanoessa macrura and larval Euphausia superba caught in winter. Comparisons show that there is intra-specific variation in length–mass relationships of several species depending on season, e.g. for the amphipod Themisto libellula. To investigate the potential use of generalized regression models, comparisons between sexes, maturity stages or age classes were performed and are discussed, such as for the several krill species and T. libellula. Regression model comparisons on age classes of the fish E. antarctica were inconclusive about their general use. Other allometric measurements performed on carapaces, eyes, heads, telsons, tails and otoliths provided models that proved to be useful for estimating length or mass in, e.g. diet studies. In some cases, the suitability of these models may depend on species or developmental stages.

Description: The Netherlands Ministry of Agriculture, Nature and Food Quality (LNV) funded this research under its Statutory Research Task Nature & Environment WOT-04-009-047.04. This research was further supported by the Netherlands Polar Programme (NPP), managed by the Dutch Research Council (NWO) under project nr. ALW 866.13.009 (ICEFLUX-NL). The study is associated with the Helmholtz Association Young Investigators Group ICEFLUX: Ice-ecosystem carbon flux in polar oceans (VH-NG-800) and contributes to the Helmholtz (HGF) research Programme Changing Earth – Sustaining our Future, Research Field Earth & Environment, Topic 6.1 and 6.3. NZ was supported by the GEOMAR project CATS: The Changing Arctic Transpolar System (BMBF-FK2 CATS). Contributions by KS were funded by the UK’s Natural Environment Research Council MOSAiC-Thematic project SYM-PEL: “Quantifying the contribution of sympagic versus pelagic diatoms to Arctic food webs and biogeochemical fluxes: application of source-specific highly branched isoprenoid biomarkers” (NE/S002502/1). BAL was further supported by the Norwegian Polar Institute and funding to M. Granskog from the Research Council of Norway to projects CAATEX (280531) and HAVOC (280292). DK was further funded by the Research Council of Norway through the project The Nansen Legacy (RCN # 276730) at the Norwegian Polar Institute. GC was further funded by the project EcoLight (03V01465) as part of the joint NERC/BMBF programme Changing Arctic Ocean. AVdP received support from Belspo in the framework the EU Lifewatch ERIC (Grant agreement FR/36/AN3) and the FEDTwin. Expedition Grant Numbers: ARK XVII/3 (PS80), AWI-PS81_01 (WISKY), ANT-XXIX/9 (PS82), AWI-PS89_02 (SIPES), AWI_PS92_00 (TRANSSIZ) and AWI_PS106/1_2-00 (SIPCA).

Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ferrick, A., Wright, V., Manga, M., & Sitar, N. Microstructural differences between naturally-deposited and laboratory beach sands. Granular Matter, 24(1), (2022): 9, https://doi.org/10.1007/s10035-021-01169-4.

Description: The orientation of, and contacts between, grains of sand reflect the processes that deposit the sands. Grain orientation and contact geometry also influence mechanical properties. Quantifying and understanding sand microstructure thus provide an opportunity to understand depositional processes better and connect microstructure and macroscopic properties. Using x-ray computed microtomography, we compare the microstructure of naturally-deposited beach sands and laboratory sands created by air pluviation in which samples are formed by raining sand grains into a container. We find that naturally-deposited sands have a narrower distribution of coordination number (i.e., the number of grains in contact) and a broader distribution of grain orientations than pluviated sands. The naturally-deposited sand grains orient inclined to the horizontal, and the pluviated sand grains orient horizontally. We explain the microstructural differences between the two different depositional methods by flowing water at beaches that re-positions and reorients grains initially deposited in unstable grain configurations.

Description: MM is supported by National Science Foundation (No. 1615203). NS is supported by National Science Foundation (No. CMMI-1853056).

Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Aguado, M. T., Ponz-Segrelles, G., Glasby, C. J., Ribeiro, R. P., Nakamura, M., Oguchi, K., Omori, A., Kohtsuka, H., Fisher, C., Ise, Y., Jimi, N., & Miura, T. Ramisyllis kingghidorahi n. Sp., a new branching annelid from Japan. Organisms Diversity & Evolution. (2022), https://doi.org/10.1007/s13127-021-00538-4.

Description: Among over 20,000 species of Annelida, only two branching species with a highly modified body-pattern are known until now: the Syllidae Syllis ramosa McIntosh, 1879, and Ramisyllis multicaudata Glasby et al. (Zoological Journal of the Linnean Society, 164, 481–497, 2012). Both have unusual ramified bodies with one head and multiple branches and live inside the canals of host sponges. Using an integrative approach (combining morphology, internal anatomy, ecology, phylogeny, genetic divergence, and the complete mitochondrial genome), we describe a new branching species from Japan, Ramisyllis kingghidorahi n. sp., inhabiting an undescribed species of Petrosia (Porifera: Demospongiae) from shallow waters. We compare the new species with its closest relative, R. multicaudata; emend the diagnosis of Ramisyllis; and discuss previous reports of S. ramosa. This study suggests a much higher diversity of branching syllids than currently known. Finally, we discuss possible explanations for the feeding behaviour in the new species in relation to its highly ciliated wall of the digestive tubes (especially at the distal branches and anus), and provide a hypothesis for the evolution of branching body patterns as the result of an adaptation to the host sponge labyrinthic canal system.

Description: Open Access funding enabled and organized by Projekt DEAL. This study was financed by the Biodiversitätsmuseum (PI:MTA), Georg August University, Göttingen, and by Grant-in Aid for Scientific Research A (No. 18H04006) (PI:TM) from the Ministry of Education, Culture, Sports, Science and Technology of Japan. GP-S was supported by the “Contratos Predoctorales para la Formación de Doctores 2016” program of MINECO, Spain (code: BES-2016–076419), co-financed by the European Social Found. RPR was supported by the program “Contratos predoctorales para Formación de Personal Investigador, FPI-UAM,” Universidad Autónoma de Madrid.

Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ganju, N. K., Couvillion, B. R., Defne, Z., & Ackerman, K. Development and application of landsat-based wetland vegetation cover and unvegetated-vegetated marsh ratio (UVVR) for the conterminous United States. Estuaries and Coasts, (2022), https://doi.org/10.1007/s12237-022-01081-x.

Description: Effective management and restoration of salt marshes and other vegetated intertidal habitats require objective and spatially integrated metrics of geomorphic status and vulnerability. The unvegetated-vegetated marsh ratio (UVVR), a recently developed metric, can be used to establish present-day vegetative cover, identify stability thresholds, and quantify vulnerability to open-water conversion over a range of spatial scales. We developed a Landsat-based approach to quantify the within-pixel vegetated fraction and UVVR for coastal wetlands of the conterminous United States, at 30-m resolution for 2014–2018. Here we present the methodology used to generate the UVVR from spectral indices, along with calibration, validation, and spatial autocorrelation assessments. We then demonstrate multiple applications of the data across varying spatial scales: first, we aggregate the UVVR across individual states and estuaries to quantify total vegetated wetland area for the nation. On the state level, Louisiana and Florida account for over 50% of the nation’s total, while on the estuarine level, the Chesapeake Bay Estuary and selected Louisiana coastal areas each account for over 6% of the nation’s total vegetated wetland area. Second, we present cases where this dataset can be used to track wetland change (e.g., expansion due to restoration and loss due to stressors). Lastly, we propose a classification methodology that delineates areas vulnerable to open-water expansion based on the 5-year mean and standard deviation of the UVVR. Calculating the UVVR for the period-of-record back to 1985, as well as regular updating, will fill a critical gap for tracking national status of salt marshes and other vegetated habitats through time and space.

Description: This work was supported by the U.S. Geological Survey’s Coastal and Marine Hazards/Resources Program.

Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Sandin, S. A., Alcantar, E., Clark, R., de Leon, R., Dilrosun, F., Edwards, C. B., Estep, A. J., Eynaud, Y., French, B. J., Fox, M. D., Grenda, D., Hamilton, S. L., Kramp, H., Marhaver, K. L., Miller, S. D., Roach, T. N. F., Seferina, G., Silveira, C. B., Smith, J. E., Zgliczynski, B. J., & Vermeij, M. J. A. Benthic assemblages are more predictable than fish assemblages at an island scale. Coral Reefs, 41, (2022.): 1031–1043, https://doi.org/10.1007/s00338-022-02272-5.

Description: Decades of research have revealed relationships between the abundance of coral reef taxa and local conditions, especially at small scales. However, a rigorous test of covariation requires a robust dataset collected across wide environmental or experimental gradients. Here, we surveyed spatial variability in the densities of major coral reef functional groups at 122 sites along a 70 km expanse of the leeward, forereef habitat of Curaçao in the southern Caribbean. These data were used to test the degree to which spatial variability in community composition could be predicted based on assumed functional relationships and site-specific anthropogenic, physical, and ecological conditions. In general, models revealed less power to describe the spatial variability of fish biomass than cover of reef builders (R2 of best-fit models: 0.25 [fish] and 0.64 [reef builders]). The variability in total benthic cover of reef builders was best described by physical (wave exposure and reef relief) and ecological (turf algal height and coral recruit density) predictors. No metric of anthropogenic pressure was related to spatial variation in reef builder cover. In contrast, total fish biomass showed a consistent (albeit weak) association with anthropogenic predictors (fishing and diving pressure). As is typical of most environmental gradients, the spatial patterns of both fish biomass density and reef builder cover were spatially autocorrelated. Residuals from the best-fit model for fish biomass retained a signature of spatial autocorrelation while the best-fit model for reef builder cover removed spatial autocorrelation, thus reinforcing our finding that environmental predictors were better able to describe the spatial variability of reef builders than that of fish biomass. As we seek to understand spatial variability of coral reef communities at the scale of most management units (i.e., at kilometer- to island-scales), distinct and scale-dependent perspectives will be needed when considering different functional groups.

Description: This research and the larger efforts of Blue Halo Curacao were supported by funding from the Waitt Institute and with permissions from the Government of Curacao, Ministry of Health, Environment, and Nature. Field logistics were further supported by the Waitt Institute vessel crew, CARMABI Foundation, The Dive Shop Curacao, and Dive Charter Curacao.

Description: Geoheritage and geodiversity visually and symbolically express the link between the physical and biological environment and cultural world. In the geoethical vision, their protection is fundamental, since they are irreplaceable components of a non-renewable social and natural ‘capital’. They become points of reference to redefine the intimate connection between human beings and Earth, thus assuming a value meaning to be placed at the basis of a new way of experiencing the territory. Initiatives such as geoparks or geotourism represent their concrete implementation, as activities capable of enhancing the environment and its geological landscape. Furthermore, their learning and enjoyment also foster a broader understanding of the significance of geosciences and their importance for the functioning of societies, as well as promoting interactions with local human communities, and the expansion of one’s spiritual and aesthetical dimension while living the interaction with nature. Responsible geotourism enhances sites and landscapes of geological significance, assuring their protection and the sustainable development of surrounding areas. Moreover, the use of those sites by citizens can increase their awareness and understanding of key issues to be faced by society, such as the sustainable use of geo-resources, the mitigation of and adaptation to climate change effects, and the reduction of risks related to natural and anthropogenic phenomena. Geotourism, therefore, also represents the common ground on which geosciences and social sciences can interact, offering undoubted advantages. It makes multidisciplinary and interdisciplinary work and cross-boundaries national and international collaboration visual and tangible; it produces an increase in public awareness and scientific knowledge; it improves the quality of life of the local population by creating incentives for economic development; finally, it drives society to behave and act more responsibly towards geodiversity and biodiversity. This chapter frames geotourism within geoethical thought, emphasising its formative contribution for the human being.

Description: Submitted

Description: 1TM. Formazione

Description: 2TM. Divulgazione Scientifica

Description: 3TM. Comunicazione

Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Womersley, F. C., Humphries, N. E., Queiroz, N., Vedor, M., da Costa, I., Furtado, M., Tyminski, J. P., Abrantes, K., Araujo, G., Bach, S. S., Barnett, A., Berumen, M. L., Bessudo Lion, S., Braun, C. D., Clingham, E., Cochran, J. E. M., de la Parra, R., Diamant, S., Dove, A. D. M., Dudgeon, C. L., Erdmann, M. V., Espinoza, E., Fitzpatrick, R., González Cano, J., Green, J. R., Guzman, H. M., Hardenstine, R., Hasan, A., Hazin, F. H. V., Hearn, A. R., Hueter, R. E., Jaidah, M. Y., Labaja, J., Ladinol, F., Macena, B. C. L., Morris Jr., J. J., Norman, B. M., Peñaherrera-Palmav, C., Pierce, S. J., Quintero, L. M., Ramırez-Macías, D., Reynolds, S. D., Richardson, A. J., Robinson, D. P., Rohner, C. A., Rowat, D. R. L., Sheaves, M., Shivji, M. S., Sianipar, A. B., Skomal, G. B., Soler, G., Syakurachman, I., Thorrold, S. R., Webb, D. H., Wetherbee, B. M., White, T. D., Clavelle, T., Kroodsma, D. A., Thums, M., Ferreira, L. C., Meekan, M. G., Arrowsmith, L. M., Lester, E. K., Meyers, M. M., Peel, L. R., Sequeira, A. M. M., Eguıluz, V. M., Duarte, C. M., & Sims, D. W. Global collision-risk hotspots of marine traffic and the world’s largest fish, the whale shark. Proceedings of the National Academy of Sciences of the United States of America, 119(20), (2022): e2117440119, https://doi.org/10.1073/pnas.2117440119.

Description: Marine traffic is increasing globally yet collisions with endangered megafauna such as whales, sea turtles, and planktivorous sharks go largely undetected or unreported. Collisions leading to mortality can have population-level consequences for endangered species. Hence, identifying simultaneous space use of megafauna and shipping throughout ranges may reveal as-yet-unknown spatial targets requiring conservation. However, global studies tracking megafauna and shipping occurrences are lacking. Here we combine satellite-tracked movements of the whale shark, Rhincodon typus, and vessel activity to show that 92% of sharks’ horizontal space use and nearly 50% of vertical space use overlap with persistent large vessel (〉300 gross tons) traffic. Collision-risk estimates correlated with reported whale shark mortality from ship strikes, indicating higher mortality in areas with greatest overlap. Hotspots of potential collision risk were evident in all major oceans, predominantly from overlap with cargo and tanker vessels, and were concentrated in gulf regions, where dense traffic co-occurred with seasonal shark movements. Nearly a third of whale shark hotspots overlapped with the highest collision-risk areas, with the last known locations of tracked sharks coinciding with busier shipping routes more often than expected. Depth-recording tags provided evidence for sinking, likely dead, whale sharks, suggesting substantial “cryptic” lethal ship strikes are possible, which could explain why whale shark population declines continue despite international protection and low fishing-induced mortality. Mitigation measures to reduce ship-strike risk should be considered to conserve this species and other ocean giants that are likely experiencing similar impacts from growing global vessel traffic.

Description: Funding for data analysis was provided by the UK Natural Environment Research Council (NERC) through a University of Southampton INSPIRE DTP PhD Studentship to F.C.W. Additional funding for data analysis was provided by NERC Discovery Science (NE/R00997/X/1) and the European Research Council (ERC-AdG-2019 883583 OCEAN DEOXYFISH) to D.W.S., Fundação para a Ciência e a Tecnologia (FCT) under PTDC/BIA/28855/2017 and COMPETE POCI-01–0145-FEDER-028855, and MARINFO–NORTE-01–0145-FEDER-000031 (funded by Norte Portugal Regional Operational Program [NORTE2020] under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund–ERDF) to N.Q. FCT also supported N.Q. (CEECIND/02857/2018) and M.V. (PTDC/BIA-COM/28855/2017). D.W.S. was supported by a Marine Biological Association Senior Research Fellowship. All tagging procedures were approved by institutional ethical review bodies and complied with all relevant ethical regulations in the jurisdictions in which they were performed. Details for individual research teams are given in SI Appendix, section 8. Full acknowledgments for tagging and field research are given in SI Appendix, section 7. This research is part of the Global Shark Movement Project (https://www.globalsharkmovement.org).

Description: This paper presents a comprehensive geological and geotechnical study of the whole area affected by liquefaction following the 2012 Emilia earthquakes, including all the available information from the field reconnaissance surveys, in situ tests, and laboratory analyses. The compilation was performed at 120 liquefied sites to verify and validate the reliability of liquefaction charts in alluvial sediments, and to assess liquefaction induced by the 2012 seismic sequence in the Emilia plain. The results reveal a wide range of grain sizes (from clean sands to sandy silts) and compositional characteristics (quartz-rich to litharenitic) in the 2012 ejecta, and show a strong relationship between the liquefaction and stratigraphic architecture of the subsurface. The availability of in situ tests at the liquefied sites makes it possible to verify and validate the reliability of the liquefaction charts in alluvial sediments with respect to the real observations. For the analyzed Emilia case studies, the use of non-liquefiable crust provides better estimations of the liquefaction manifestations when coupled with the thickness of the liquefiable layer rather than with the liquefaction potential index. Altogether, this work makes available to the international scientific community a consistent liquefaction database for in-depth earthquake studies

Description: Published

Description: 3659–3697

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: JCR Journal

Description: Erklärt, wie eine Pandemie modelliert wird. Erläutert, welche Probleme sich mit Modellen lösen lassen und wo die Grenzen liegen. Bietet Orientierung in der Unübersichtlichkeit der Corona-Situation. Die COVID-19-Pandemie hat weltweit dramatische Folgen. Mathematische Modelle spielen bei ihrer Bewertung eine zentrale Rolle: Sie sollen die Wirkung von Maßnahmen abschätzen, die oft mit Einschränkungen individueller Freiheiten einhergehen. Umso mehr sollte das Wissen um die Mathematik der Pandemie nicht nur Experten überlassen bleiben. Dieses Buch erläutert grundlegende Begriffe und Modelle, und klärt weitverbreitete Missverständnisse auf. Das Buch gibt insbesondere Antwort auf folgende Fragen: Was sagen Kennzahlen wie Inzidenz, Reproduktionszahl, Hospitalisierungsrate oder Impfquote über die Pandemie? Was ist der Unterschied von linearem und exponentiellem Wachstum? Was ist Herdenimmunität? Warum werden sich trotz Herdenimmunität fast alle Ungeimpften anstecken? Was ist der Effekt von Kontaktbeschränkungen und Impfung? Warum sind Vorhersagen in der Pandemie schwierig?

Description: Renate Treffeisen und Klaus Grosfeld zeigen in ihren Beitrag, vor welchen Herausforderungen es beim Thema „Kimawandel“ aus dem Blickwinkel der Wissenschaftskommunikation geht. Sie appellieren zunächst dafür, statt von „Klimawandel" von „Klimakrise“ zu sprechen, damit der Blick auf Ursache, Dringlichkeit und den politischen Charakter des Problems in den Vordergrund tritt. Die Fridays4Future- und Scientists4Future-Bewegungen stünden dabei für ein Bottom-Up-Agenda-Setting, das Akteure zu Interaktion und Dialogbereitschaft auffordere. Treffeisen und Grosfeld erläutern daraufhin zwei Medienprojekte für erfolgreichen Wissenstransfer aus dem Forschungsverbund REKLIM.

Description: The relation between macroseismic intensity and ground shaking makes it possible to transform instrumental Ground Motion Parameters (GMPs) in macroseismic intensity and vice versa, and is therefore useful for making comparisons between estimates of seismic hazard determined in terms of GMPs and macroseismic intensity, and for other engineering and seismological applications. Empirical relationships between macroseismic intensity and different recorded GMPs for the Italian territory are presented in this paper. The coefficients are calibrated using a dataset of horizontal geometrical mean GMPs, i.e. peak ground acceleration (PGA), peak ground velocity (PGV), spectral acceleration (SA) at 0.2, 0.3, 1.0 and 2.0 s from the ITalian ACcelerometric Archive (ITACA; Luzi et al. 2019), and macroseismic intensity at Mercalli-Cancani-Sieberg (MCS) scale from the database DBMI15 (Locati et al. 2019). A dataset was obtained that corresponds to 240 pairs of macroseismic intensity-GMPs from 67 Italian earthquakes in the time window 1972-2016 with moment magnitude ranging from 4.2 to 6.8 and macroseismic intensity in the range [2, 10-11]. The final dataset is developed correlating strong motion stations and macroseismic intensity observations generally within 2 km from each other, but the associations is manually validated through the expert opinion. The adopted functional form is non-linear predicting macroseismic intensity as a function of LogGMPs and vice versa by performing separate regressions. The set of empirical conversion relationships GMP-I MCS -GMP and the associated standard deviations are compared with previous models. The results of an illustrative PSHA, obtained using a new seismogenic zonation (Santulin et al. 2017), proposed as one of the inputs of the new Italian seismic hazard model (Meletti et al. 2017), are used to analyse and compare seismic hazard assessment in terms of PGA and the related seismic hazard map in terms of macroseismic intensity (MCS) obtained using the empirical relationships here proposed for the PGA.

Description: Published

Description: 5143–5164

Description: 6T. Studi di pericolosità sismica e da maremoto

Description: JCR Journal

Description: This chapter is arguably the most complete compilation of sulfur volcanism of any given volcano on Earth: Poás. Sulfur volcanism at Poás is described in historical literature since 1828, and in scientific literature since the 1960’s. We first classify the various manifestations of sulfur volcanism at crater lake bearing volcanoes (subaerial and sublacustrine sulfur pools, sulfur spherules, flows, cones/hornitos, and sweat, and pyroclastic and burning sulfur), based on work by Japanese pioneers of the early 1900s. Their first observations and models have passed the test of time and still stand as theories today. Comparing the sulfur volcanism at Poás with the one at other (55) volcanoes, it is honest to say that only White Island (New Zealand) and Kawah Ijen (Indonesia) are the only ones comparable with Poás, being the most dynamic of them all.

Description: Published

Description: 45-78

Description: 4V. Processi pre-eruttivi