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Author Charles Amory, Christoph Kittel, Louis Le Toumelin, Cécile Agosta, Alison Delhasse, Vincent Favier, Xavier Fettweis doi  openurl
  Title (up) Performance of MAR (v3.11) in simulating the drifting-snow climate and surface mass balance of Adélie Land, East Antarctica Type Journal
  Year 2021 Publication Geoscientific Model Development Abbreviated Journal  
  Volume 14 Issue 6 Pages 3487-3510  
  Keywords  
  Abstract

Abstract. Drifting snow, or the wind-driven transport of snow particles originating from clouds and the surface below and above 2 m above ground and their concurrent sublimation, is a poorly documented process on the Antarctic ice sheet, which is inherently lacking in most climate models. Since drifting snow mostly results from erosion of surface particles, a comprehensive evaluation of this process in climate models requires a concurrent assessment of simulated drifting-snow transport and the surface mass balance (SMB). In this paper a new version of the drifting-snow scheme currently embedded in the regional climate model MAR (v3.11) is extensively described. Several important modifications relative to previous version have been implemented and include notably a parameterization for drifting-snow compaction of the uppermost snowpack layer, differentiated snow density at deposition between precipitation and drifting snow, and a rewrite of the threshold friction velocity above which snow erosion initiates. Model results at high resolution (10 km) over Adélie Land, East Antarctica, for the period 2004–2018 are presented and evaluated against available near-surface meteorological observations at half-hourly resolution and annual SMB estimates. The evaluation demonstrates that MAR resolves the local drifting-snow frequency and transport up to the scale of the drifting-snow event and captures the resulting observed climate and SMB variability, suggesting that this model version can be used for continent-wide applications.

 
  Programme 411  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1991-959X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8428  
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Author Jesús A Ballesteros, Emily V W Setton, Carlos E Santibáñez-López, Claudia P Arango, Georg Brenneis, Saskia Brix, Kevin F Corbett, Esperanza Cano-Sánchez, Merai Dandouch, Geoffrey F Dilly, Marc P Eleaume, Guilherme Gainett, Cyril Gallut, Sean McAtee, Lauren McIntyre, Amy L Moran, Randy Moran, Pablo J López-González, Gerhard Scholtz, Clay Williamson, H Arthur Woods, Jakob T Zehms, Ward C Wheeler, Prashant P Sharma doi  openurl
  Title (up) Phylogenomic Resolution of Sea Spider Diversification through Integration of Multiple Data Classes Type Journal
  Year 2021 Publication Molecular Biology and Evolution Abbreviated Journal  
  Volume 38 Issue 2 Pages 686-701  
  Keywords  
  Abstract Despite significant advances in invertebrate phylogenomics over the past decade, the higher-level phylogeny of Pycnogonida (sea spiders) remains elusive. Due to the inaccessibility of some small-bodied lineages, few phylogenetic studies have sampled all sea spider families. Previous efforts based on a handful of genes have yielded unstable tree topologies. Here, we inferred the relationships of 89 sea spider species using targeted capture of the mitochondrial genome, 56 conserved exons, 101 ultraconserved elements, and 3 nuclear ribosomal genes. We inferred molecular divergence times by integrating morphological data for fossil species to calibrate 15 nodes in the arthropod tree of life. This integration of data classes resolved the basal topology of sea spiders with high support. The enigmatic family Austrodecidae was resolved as the sister group to the remaining Pycnogonida and the small-bodied family Rhynchothoracidae as the sister group of the robust-bodied family Pycnogonidae. Molecular divergence time estimation recovered a basal divergence of crown group sea spiders in the Ordovician. Comparison of diversification dynamics with other marine invertebrate taxa that originated in the Paleozoic suggests that sea spiders and some crustacean groups exhibit resilience to mass extinction episodes, relative to mollusk and echinoderm lineages.  
  Programme 1124  
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  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1537-1719 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8246  
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Author N. Aubone, M. Saraceno, M. L. Torres Alberto, J. Campagna, L. Le Ster, B. Picard, M. Hindell, C. Campagna, C. R. Guinet doi  openurl
  Title (up) Physical changes recorded by a deep diving seal on the Patagonian slope drive large ecological changes Type Journal
  Year 2021 Publication Journal of Marine Systems Abbreviated Journal  
  Volume 223 Issue Pages 103612  
  Keywords Elephant seals Malvinas current Patagonian shelf slope Southwestern Atlantic Ocean  
  Abstract The Patagonian slope is the region where Subantarctic waters and bathymetry give raise to physical and ecological processes that support a rich biodiversity and a large-scale industrial fisheries. Unique among the species that depend on this region is the deep diving southern elephant seal, Mirounga leonina. We report here on changes in the foraging behavior of a female seal explained by the combined effect of a cold and high salinity water mass and a decrease in surface chlorophyll-a concentration. Behavioral and oceanographic data from about 5000 profiles of temperature, conductivity, pressure, light and prey encounters were collected within an area ranging 59.5–61°W and 46–47.5°S, at depths of 300–700 m, on the Patagonian slope, during November–December 2018. A decrease in temperature (0.15 °C) and an increase in salinity (0.03) was found below the mixed layer, during December. Light data revealed a significant increase of irradiance in December (almost reaching the ocean bottom) associated with a decrease of chlorophyll-a in the upper levels. Concomitantly, the seal had a different diving behavior in December, foraging near the surface at night and close to the bottom during daylight hours. Also, the seal doubled the prey capture attempts in December compared to November. This study reveals the importance of ocean physical properties on seal's diving and foraging behavior, and how this changes, although small, can impact on seals diet and body composition during their post-breeding trips.  
  Programme 1201  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0924-7963 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8771  
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Author Rebekah I. Dawson, Chelsea X. Huang, Rafael Brahm, Karen A. Collins, Melissa J. Hobson, Andrés Jordán, Jiayin Dong, Judith Korth, Trifon Trifonov, Lyu Abe, Abdelkrim Agabi, Ivan Bruni, R. Paul Butler, Mauro Barbieri, Kevin I. Collins, Dennis M. Conti, Jeffrey D. Crane, Nicolas Crouzet, Georgina Dransfield, Phil Evans, Néstor Espinoza, Tianjun Gan, Tristan Guillot, Thomas Henning, Jack J. Lissauer, Eric L. N. Jensen, Wenceslas Marie Sainte, Djamel Mékarnia, Gordon Myers, Sangeetha Nandakumar, Howard M. Relles, Paula Sarkis, Pascal Torres, Stephen Shectman, François-Xavier Schmider, Avi Shporer, Chris Stockdale, Johanna Teske, Amaury H. M. J. Triaud, Sharon Xuesong Wang, Carl Ziegler, G. Ricker, R. Vanderspek, David W. Latham, S. Seager, J. Winn, Jon M. Jenkins, L. G. Bouma, Jennifer A. Burt, David Charbonneau, Alan M. Levine, Scott McDermott, Brian McLean, Mark E. Rose, Andrew Vanderburg, Bill Wohler doi  openurl
  Title (up) Precise Transit and Radial-velocity Characterization of a Resonant Pair: The Warm Jupiter TOI-216c and Eccentric Warm Neptune TOI-216b Type Journal
  Year 2021 Publication The Astronomical Journal Abbreviated Journal  
  Volume 161 Issue 4 Pages 161  
  Keywords  
  Abstract TOI-216 hosts a pair of warm, large exoplanets discovered by the TESS mission. These planets were found to be in or near the 2:1 resonance, and both of them exhibit transit timing variations (TTVs). Precise characterization of the planets’ masses and radii, orbital properties, and resonant behavior can test theories for the origins of planets orbiting close to their stars. Previous characterization of the system using the first six sectors of TESS data suffered from a degeneracy between planet mass and orbital eccentricity. Radial-velocity measurements using HARPS, FEROS, and the Planet Finder Spectrograph break that degeneracy, and an expanded TTV baseline from TESS and an ongoing ground-based transit observing campaign increase the precision of the mass and eccentricity measurements. We determine that TOI-216c is a warm Jupiter, TOI-216b is an eccentric warm Neptune, and that they librate in 2:1 resonance with a moderate libration amplitude of deg, a small but significant free eccentricity of for TOI-216b, and a small but significant mutual inclination of 1.°2–3.°9 (95% confidence interval). The libration amplitude, free eccentricity, and mutual inclination imply a disturbance of TOI-216b before or after resonance capture, perhaps by an undetected third planet.  
  Programme 1066  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1538-3881 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8194  
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Author Christophe Barbraud, Baudouin des Monstiers, Adrien Chaigne, Cédric Marteau, Henri Weimerskirch, Karine Delord doi  openurl
  Title (up) Predation by feral cats threatens great albatrosses Type Journal
  Year 2021 Publication Biological Invasions Abbreviated Journal  
  Volume 23 Issue 8 Pages 2389-2405  
  Keywords  
  Abstract Feral cats (Felis catus) are a potential threat for several seabird species including medium sized albatrosses, but studies documenting predation behavior, demographic impacts and effects of predator control are scarce. Here, we present data on feral cat predation behavior on one of the world’s largest seabirds, the wandering albatross (Diomedea exulans) at Kerguelen Island, and show how it affects breeding success and rate of population growth. We assess the effect of a feral cat control experiment on breeding success and population viability. Using 32 camera traps we monitored 25 nests of albatross and detected 295 events showing a potential predator. Of these, 75.2% and 24.8% involved feral cats and giant petrels, respectively. Giant petrels were never implicated in direct predation. We recorded 17 attacks of feral cats on 13 albatross chicks. Attacks lasted in average 52.1 ± 72.9 min, and resulted in the death of 10 of the 13 (76.9%) monitored chicks. Breeding success where attacks were recorded was low (12%) compared to areas with no attack (86%). Mean breeding success during 3 years before cat control was 26% and increased to 80% during the 3 years following the experiment. According to predation scenarios, population modelling showed that the albatross population would decline by 2.7–4.5% per year without cat control. Following cat control the population would increase at 1.8% per year. Our results demonstrate that feral cats predate and have negative impacts on breeding success and population growth rate of wandering albatrosses at Kerguelen Island. We provide recommendations on feral cat control and eradication to mitigate the risk of population decline or local extinction of large albatrosses.  
  Programme 109  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1573-1464 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7938  
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Author Carlo Cauzzi, Susana Custódio, Christos P. Evangelidis, Giovanni Lanzano, Lucia Luzi, Lars Ottemöller, Helle Pedersen, Reinoud Sleeman doi  openurl
  Title (up) Preface to the Focus Section on European Seismic Networks and Associated Services and Products Type Journal
  Year 2021 Publication Seismological Research Letters Abbreviated Journal  
  Volume 92 Issue 3 Pages 1483-1490  
  Keywords  
  Abstract Most of the articles of this focus section serve as good examples in the open science domain, in which data are expected to be “findable, accessible, interoperable, and reusable” (Wilkinson et al., 2016). In many contributions, emphasis is placed on quality: as automated access to seismological archives via standardized web services emerges as the preferred user strategy, ensuring the high quality of data and metadata becomes more and more important (e.g., Büyükakpınar et al., 2021; Cambaz et al., 2021; Carrilho et al., 2021; Evangelidis et al., 2021; Mader and Ritter, 2021; Ottemöller et al., 2021; Péquegnat et al., 2021; Stammler et al., 2021; Strollo et al., 2021). Quality is especially important at a time when very large datasets are increasingly being processed routinely and “blindly” in machine‐learning approaches. The vast majority of seismological data centers already manage multisensor archives (seismometers, accelerometers, infrasound, amphibian seismological instruments, high‐rate global navigation satellite systems, etc.), and the inclusion of new types of data (e.g., rotational sensors, low‐cost instrumentation, and synthetic waveforms) in seismological archives poses new challenges and prompts for new technical solutions and standards for data archiving, metadata preparation, quality checks, data dissemination, and processing. A particular challenge over the next few years (Quinteros, Carter, et al., 2021) is the upcoming massive growth of data volume, due in particular to new instruments (large‐N experiments and distributed acoustic sensing systems) but also to increased volumes of traditional seismic data. It is expected that multisensor experiments will progressively dominate the technical and scientific discussion in geosciences in the coming decade, spurred by the societal need to develop multidisciplinary, multihazard science and research products. Joining forces and competences is therefore key to addressing future challenges: the EarthScope Consortium was recently established in the United States, and the European Plate Observing System (EPOS) was created as the framework to integrate all geoscience services in the greater European region. ORFEUS and its seismic network community strongly support the development and consolidation of EPOS by participating in the activities of its thematic core service for seismology.  
  Programme 133  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0895-0695 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8429  
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Author É Vignon, M.-L. Roussel, I. V. Gorodetskaya, C. Genthon, A. Berne file  doi
openurl 
  Title (up) Present and Future of Rainfall in Antarctica Type Journal
  Year 2021 Publication Geophysical Research Letters Abbreviated Journal  
  Volume 48 Issue 8 Pages e2020GL092281  
  Keywords  
  Abstract While most precipitation in Antarctica falls as snow, little is known about liquid precipitation, although it can have ecological and climatic impacts. This study combines meteorological reports at 10 stations with the ERA5 reanalysis to provide a climatological characterization of rainfall occurrence over Antarctica. Along the East Antarctic coast, liquid precipitation occurs 22 days per year at most and coincides with maritime intrusions and blocking anticyclones. Over the north-western Antarctic Peninsula, rainfall occurs more than 50 days per year on average and the recent summer cooling was accompanied by a decrease of −35 annual rainy days per decade between 1998 and 2015 at Faraday-Vernadsky. Projections from seven latest-generation climate models reveal that Antarctic coasts will experience a warming and more frequent and intense rainfall by the end of the century. Rainfall is expected to impact new regions of the continent, increasing their vulnerability to melting by the preconditioning of surface snow.  
  Programme 1013,1143  
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  Address  
  Corporate Author Thesis Bachelor's thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1944-8007 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7935  
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Author John P. Whiteman, Seth D. Newsome, Paco Bustamante, Yves Cherel, Keith A. Hobson doi  openurl
  Title (up) Quantifying capital versus income breeding: New promise with stable isotope measurements of individual amino acids Type Journal
  Year 2021 Publication Journal of Animal Ecology Abbreviated Journal  
  Volume 90 Issue 6 Pages 1408-1418  
  Keywords carbon-13 compound-specific isotope analysis CSIA discrimination fasting fractionation nitrogen-15  
  Abstract Capital breeders accumulate nutrients prior to egg development, then use these stores to support offspring development. In contrast, income breeders rely on local nutrients consumed contemporaneously with offspring development. Understanding such nutrient allocations is critical to assessing life-history strategies and habitat use. Despite the contrast between these strategies, it remains challenging to trace nutrients from endogenous stores or exogenous food intake into offspring. Here, we tested a new solution to this problem. Using tissue samples collected opportunistically from wild emperor penguins Aptenodytes forsteri, which exemplify capital breeding, we hypothesized that the stable carbon (δ13C) and nitrogen (δ15N) isotope values of individual amino acids (AAs) in endogenous stores (e.g. muscle) and in egg yolk and albumen reflect the nutrient sourcing that distinguishes capital versus income breeding. Unlike other methods, this approach does not require untested assumptions or diet sampling. We found that over half of essential AAs had δ13C values that did not differ between muscle and yolk or albumen, suggesting that most of these AAs were directly routed from muscle into eggs. In contrast, almost all non-essential AAs differed in δ13C values between muscle and yolk or between muscle and albumen, suggesting de novo synthesis. Over half of AAs that have labile nitrogen atoms (i.e. ‘trophic’ AA) had higher δ15N values in yolk and albumen than in muscle, suggesting that they were transaminated during their routing into egg tissue. This effect was smaller for AAs with less labile nitrogen atoms (i.e. ‘source’ AA). Our results indicate that the δ15N offset between trophic-source AAs (Δ15Ntrophic-source) may provide an index of the extent of capital breeding. The value of emperor penguin Δ15NPro-Phe was higher in yolk and albumen than in muscle, reflecting the mobilization of endogenous stores; in comparison, the value of Δ15NPro-Phe was similar across muscle and egg tissue in previously published data for income-breeding herring gulls Larus argentatus smithsonianus. Our results provide a quantitative basis for using AA δ13C and δ15N, and isotopic offsets among AAs (e.g. Δ15NPro-Phe), to explore the allocation of endogenous versus exogenous nutrients across the capital versus income spectrum of avian reproduction.  
  Programme 109  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1365-2656 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7945  
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Author Fanny Larue, Ghislain Picard, Jérémie Aublanc, Laurent Arnaud, Alvaro Robledano-Perez, Emmanuel LE Meur, Vincent Favier, Bruno Jourdain, Joel Savarino, Pierre Thibaut doi  openurl
  Title (up) Radar altimeter waveform simulations in Antarctica with the Snow Microwave Radiative Transfer Model (SMRT) Type Journal
  Year 2021 Publication Remote Sensing of Environment Abbreviated Journal  
  Volume 263 Issue Pages 112534  
  Keywords Antarctic ice sheet Field measurements Modeling Radar altimetry Remote sensing SMRT Waveform  
  Abstract Radar altimeters are important tools to monitor the volume of the ice sheets. The penetration of radar waves in the snowpack is a major source of uncertainty to retrieve surface elevation. To correct this effect, a better understanding of the sensitivity of the radar waveforms to snow properties is needed. Here, we present an extension of the Snow Model Radiative Transfer (SMRT) to compute radar waveforms and conduct a series of simulations on the Antarctic ice sheet. SMRT is driven by snow and surface roughness properties measured over a large latitudinal range during two field campaigns on the Antarctic Plateau. These measurements show that the snowpack is rougher, denser, less stratified, warmer, and has smaller snow grains near the coast than on the central Plateau. These simulations are compared to satellite observations in the Ka, Ku, and S bands. SMRT reproduces the observed waveforms well. For all sites and all sensors, the main contribution comes from the surface echo. The echo from snow grains (volume scattering) represents up to 40% of the amplitude of the total waveform power in the Ka band, and less at the lower frequencies. The highest amplitude is observed on the central Plateau due to the combination of higher reflection from the surface, higher scattering by snow grains in the Ka and Ku bands, and higher inter-layer reflections in the S band. In the Ka band, the wave penetrates in the snowpack less deeply on the central Plateau than near the coast because of the strong scattering caused by the larger snow grains. The opposite is observed in the S band, the wave penetrates deeper on the central Plateau because of the lower absorption due to the lower snow temperatures. The elevation bias caused by wave penetration into the snowpack show a constant bias of 10 cm for all sites in the Ka band, and a bias of 11 cm, and 21 cm in the Ku band for sites close to the coast and the central Plateau, respectively. Now that SMRT is performing waveform simulations, further work will address how the snowpack properties affect the parameters retrieved by more advanced retracking algorithms such as ICE-2 for different snow cover surfaces.  
  Programme 1110  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0034-4257 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7997  
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Author Karl-Ludwig Klein doi  openurl
  Title (up) Radio Astronomical Tools for the Study of Solar Energetic Particles I. Correlations and Diagnostics of Impulsive Acceleration and Particle Propagation Type Journal
  Year 2021 Publication Frontiers in Astronomy and Space Sciences Abbreviated Journal  
  Volume 7 Issue Pages 105  
  Keywords  
  Abstract Solar energetic particles (SEPs) are sporadically ejected from the Sun during flares and coronal mass ejections. They are of major astrophysical interest, because the proximity of the Sun allows for detailed multi-messenger studies. They affect space weather due to interactions with electronics, with the Earth’s atmosphere, and with humans if they leave the protective shield of the magnetosphere of the Earth. Since early studies in the 1950s, starting with particle detectors on the ground, SEP events have been related to radio bursts. Two subjects are addressed in this chapter: attempts to establish quantitative correlations between SEPs and microwave bursts produced by gyro synchrotron radiation of mildly relativistic electrons, and the information derived from type III radio bursts on impulsive processes of particle acceleration and the coronal and interplanetary propagation. Type III radio bursts produced by electron beams on open magnetic field lines have a wide range of applications, including the identification of acceleration regions, the identification of confined particle acceleration with coronal signatures, but no SEPs, and the paths that the electrons, and energetic charged particles in general, take to travel from the low corona to the Heliosphere in case they escape. Simple scenarios of coronal particle acceleration are confirmed in relatively simple and short events. But the comparison with particle transport models shows that longer and delayed acceleration episodes exist especially in large SEP events. They will be discussed in a companion chapter.  
  Programme 227  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2296-987X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6775  
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