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Author Akers P., Savarino, J., Caillon, N. openurl 
  Title (down) Reconstructing Antarctic snow accumulation using nitrogen isotopes of nitrate Type Communication
  Year 2021 Publication EGU General Assembly, 19-30 April 2021 Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract  
  Programme 1177  
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  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7866  
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Author Benjamin Pohl, Thomas Saucède, Vincent Favier, Julien Pergaud, Deborah Verfaillie, Jean-Pierre Féral, Ylber Krasniqi, Yves Richard file  doi
openurl 
  Title (down) Recent Climate Variability around the Kerguelen Islands (Southern Ocean) Seen through Weather Regimes Type Journal
  Year 2021 Publication Journal of Applied Meteorology and Climatology Abbreviated Journal  
  Volume 60 Issue 5 Pages 711-731  
  Keywords  
  Abstract Daily Weather Regimes Are Defined Around The Kerguelen Islands (Southern Ocean) On The Basis Of Daily 500-hpa Geopotential Height Anomalies Derived From The Era5 Ensemble Reanalysis Over The Period 1979–2018. Ten Regimes Are Retained As Significant. Their Occurrences Are Highly Consistent Across Reanalysis Ensemble Members. Regimes Show Weak Seasonality And Nonsignificant Long-term Trends In Their Occurrences. Their Sequences Are Usually Short (1–3 Days), With Extreme Persistence Values Above 10 Days. Seasonal Regime Frequency Is Mostly Driven By The Phase Of The Southern Annular Mode Over Antarctica, Midlatitude Dynamics Over The Southern Ocean Such As The Pacific–south American Mode, And, To A Lesser Extent, Tropical Variability, With Significant But Weaker Relationships With El Niño–southern Oscillation. At The Local Scale Over The Kerguelen Islands, Regimes Have A Strong Influence On Measured Atmospheric And Oceanic Variables, Including Minimum And Maximum Air Temperature, Mostly Driven By Horizontal Advections, Seawater Temperature Recorded 5 M Below The Surface, Wind Speed, And Sea Level Pressure. Relationships Are Weaker For Precipitation Amounts. Regimes Also Modify Regional Contrasts Between Observational Sites In Kerguelen, Highlighting Strong Exposure Contrasts. The Regimes Allow Us To Improve Our Understanding Of Weather And Climate Variability And Interactions In This Region; They Will Be Used In Future Work To Assess Past And Projected Long-term Circulation Changes In The Southern Midlatitudes.  
  Programme 688,1044,1048  
  Campaign  
  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 1558-8424 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8003  
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Author Yushiro Fujii, Kenji Satake, Shingo Watada, Tung-Cheng Ho doi  openurl
  Title (down) Re-examination of Slip Distribution of the 2004 Sumatra–Andaman Earthquake (Mw 9.2) by the Inversion of Tsunami Data Using Green’s Functions Corrected for Compressible Seawater Over the Elastic Earth Type Journal
  Year 2021 Publication Pure and Applied Geophysics Abbreviated Journal  
  Volume 178 Issue 12 Pages 4777-4796  
  Keywords 2004 Sumatra–Andaman earthquake far-field tsunami waveform phase-corrected Green’s function slip distribution tsunami data inversion  
  Abstract We re-examined the slip distribution on faults of the 2004 Sumatra–Andaman (M 9.1 according to USGS) earthquake by the inversion of tsunami data with phase-corrected Green’s functions applied to linear long waves. The correction accounts for the effects of compressibility of seawater, elasticity of solid earth, and gravitational potential variation associated with the motion of mass to reproduce the delayed arrivals and the reversed phase of the first tsunami waves. We used sea surface height (SSH) data from satellite altimetry (SA) measurements along five tracks, and the tsunami waveforms recorded at tide gauges (TGs) and ocean bottom pressure gauges (OBPGs) in and around the Indian Ocean. The inversion results for both data sets for different rupture velocities (Vr) show that the reproducibility of the spatiotemporal SSHs and tsunami waveforms is improved by the phase corrections, although the effects are not so significant within the Indian Ocean. The best slip distribution model from joint inversion of SA, TG and OBPG data with Vr of 1.3 km/s shows the largest slips of 16–25 m off Sumatra Island, large slips of 2–11 m off the Nicobar Islands, and moderate slips of 2–6 m in the Andaman Islands. The inversion results reproduce the far-field tsunami waveforms well at distant stations even more than 13,000–25,000 km from the epicenter. The total source length is about 1400 km and the seismic moment is Mw 9.2, longer and larger than that of our previous estimates based on TG records.  
  Programme 688  
  Campaign  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1420-9136 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8411  
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Author Karl-Ludwig Klein doi  openurl
  Title (down) Radio Astronomical Tools for the Study of Solar Energetic Particles II.Time-Extended Acceleration at Subrelativistic and Relativistic Energies Type Journal
  Year 2021 Publication Frontiers in Astronomy and Space Sciences Abbreviated Journal  
  Volume 7 Issue Pages 93  
  Keywords  
  Abstract Solar energetic particle (SEP) events are commonly separated in two categories: numerous “impulsive” events of relatively short duration, and a few “gradual” events, where SEP-intensities may stay enhanced over several days at energies up to several tens of MeV. In some gradual events the SEP spectrum extends to relativistic energies (>1 GeV), over shorter durations. The two categories are strongly related to an idea developed in the 1960s based on radio observations: Type III bursts, which were addressed in a companion chapter, outline impulsive acceleration of electrons to subrelativistic energies, while the large and the relativistic SEP events were ascribed to a second acceleration process. At radio wavelengths, typical counterparts were bursts emitted by electrons accelerated at coronal shock waves (type II bursts) and by electron populations in large-scale closed coronal structures (type IV bursts). Both burst types are related to coronal mass ejections (CMEs). Type II bursts from metric to kilometric wavelengths tend to accompany large SEP events, which is widely considered as a confirmation that CME-driven shocks accelerate the SEPs. But type II bursts, especially those related to SEP events, are most often accompanied by type IV bursts, where the electrons are rather accelerated in the wake of the CME. Individual event studies suggest that although the CME shock is the most plausible accelerator of SEPs up to some yet unknown limiting energy, the relativistic SEP events show time structure that rather points to coronal acceleration related to type IV bursts. This chapter addresses the question what type II bursts tell us about coronal shock waves and how type II and type IV radio bursts are related with relativistic proton signatures as seen by particle detectors on the Earth and by their gamma-ray emission in the solar atmosphere, focusing on two relativistic SEP events, on 2005 Jan 20 and 2017 Sep 10. The importance of radio emissions as a complement to the upcoming SEP observations from close to the Sun is underlined.  
  Programme 227  
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  Corporate Author Thesis  
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  Language Summary Language Original Title  
  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 7777  
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Author Karl-Ludwig Klein doi  openurl
  Title (down) 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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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  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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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 (down) 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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  Corporate Author Thesis  
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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 John P. Whiteman, Seth D. Newsome, Paco Bustamante, Yves Cherel, Keith A. Hobson doi  openurl
  Title (down) 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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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  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 É Vignon, M.-L. Roussel, I. V. Gorodetskaya, C. Genthon, A. Berne file  doi
openurl 
  Title (down) 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  
  Campaign  
  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  
Permanent link to this record
 

 
Author Carlo Cauzzi, Susana Custódio, Christos P. Evangelidis, Giovanni Lanzano, Lucia Luzi, Lars Ottemöller, Helle Pedersen, Reinoud Sleeman doi  openurl
  Title (down) 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 Christophe Barbraud, Baudouin des Monstiers, Adrien Chaigne, Cédric Marteau, Henri Weimerskirch, Karine Delord doi  openurl
  Title (down) 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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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  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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