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Author Andrés Barbosa, Arvind Varsani, Virginia Morandini, Wray Grimaldi, Ralph E. T. Vanstreels, Julia I. Diaz, Thierry Boulinier, Meagan Dewar, Daniel González-Acuña, Rachael Gray, Clive R. McMahon, Gary Miller, Michelle Power, Amandine Gamble, Michelle Wille doi  openurl
  Title Risk assessment of SARS-CoV-2 in Antarctic wildlife Type Journal
  Year 2021 Publication Science of The Total Environment Abbreviated Journal  
  Volume 755 Issue Pages 143352  
  Keywords Antarctica Coronavirus COVID-19 Mitigation measures Reverse zoonoses Transmission  
  Abstract The coronavirus disease 2019 (COVID-19) pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This pathogen has spread rapidly across the world, causing high numbers of deaths and significant social and economic impacts. SARS-CoV-2 is a novel coronavirus with a suggested zoonotic origin with the potential for cross-species transmission among animals. Antarctica can be considered the only continent free of SARS-CoV-2. Therefore, concerns have been expressed regarding the potential human introduction of this virus to the continent through the activities of research or tourism to minimise the effects on human health, and the potential for virus transmission to Antarctic wildlife. We assess the reverse-zoonotic transmission risk to Antarctic wildlife by considering the available information on host susceptibility, dynamics of the infection in humans, and contact interactions between humans and Antarctic wildlife. The environmental conditions in Antarctica seem to be favourable for the virus stability. Indoor spaces such as those at research stations, research vessels or tourist cruise ships could allow for more transmission among humans and depending on their movements between different locations the virus could be spread across the continent. Among Antarctic wildlife previous in silico analyses suggested that cetaceans are at greater risk of infection whereas seals and birds appear to be at a low infection risk. However, caution needed until further research is carried out and consequently, the precautionary principle should be applied. Field researchers handling animals are identified as the human group posing the highest risk of transmission to animals while tourists and other personnel pose a significant risk only when in close proximity (< 5 m) to Antarctic fauna. We highlight measures to reduce the risk as well as identify of knowledge gaps related to this issue.  
  Programme 1151  
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  ISSN (down) 0048-9697 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 7960  
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Author Elena Angulo, Christophe Diagne, Liliana Ballesteros-Mejia, Tasnime Adamjy, Danish A. Ahmed, Evgeny Akulov, Achyut K. Banerjee, César Capinha, Cheikh A. K. M. Dia, Gauthier Dobigny, Virginia G. Duboscq-Carra, Marina Golivets, Phillip J. Haubrock, Gustavo Heringer, Natalia Kirichenko, Melina Kourantidou, Chunlong Liu, Martin A. Nuñez, David Renault, David Roiz, Ahmed Taheri, Laura N. H. Verbrugge, Yuya Watari, Wen Xiong, Franck Courchamp doi  openurl
  Title Non-English languages enrich scientific knowledge: The example of economic costs of biological invasions Type Journal
  Year 2021 Publication Science of The Total Environment Abbreviated Journal  
  Volume 775 Issue Pages 144441  
  Keywords Ecological bias InvaCost Knowledge gaps Management Native languages Stakeholders  
  Abstract We contend that the exclusive focus on the English language in scientific research might hinder effective communication between scientists and practitioners or policy makers whose mother tongue is non-English. This barrier in scientific knowledge and data transfer likely leads to significant knowledge gaps and may create biases when providing global patterns in many fields of science. To demonstrate this, we compiled data on the global economic costs of invasive alien species reported in 15 non-English languages. We compared it with equivalent data from English documents (i.e., the InvaCost database, the most up-to-date repository of invasion costs globally). The comparison of both databases (~7500 entries in total) revealed that non-English sources: (i) capture a greater amount of data than English sources alone (2500 vs. 2396 cost entries respectively); (ii) add 249 invasive species and 15 countries to those reported by English literature, and (iii) increase the global cost estimate of invasions by 16.6% (i.e., US$ 214 billion added to 1.288 trillion estimated from the English database). Additionally, 2712 cost entries — not directly comparable to the English database — were directly obtained from practitioners, revealing the value of communication between scientists and practitioners. Moreover, we demonstrated how gaps caused by overlooking non-English data resulted in significant biases in the distribution of costs across space, taxonomic groups, types of cost, and impacted sectors. Specifically, costs from Europe, at the local scale, and particularly pertaining to management, were largely under-represented in the English database. Thus, combining scientific data from English and non-English sources proves fundamental and enhances data completeness. Considering non-English sources helps alleviate biases in understanding invasion costs at a global scale. Finally, it also holds strong potential for improving management performance, coordination among experts (scientists and practitioners), and collaborative actions across countries. Note: non-English versions of the abstract and figures are provided in Appendix S5 in 12 languages.  
  Programme 136  
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  ISSN (down) 0048-9697 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 7973  
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Author Céline Albert, Hálfdán Helgi Helgason, Maud Brault-Favrou, Gregory J. Robertson, Sébastien Descamps, Françoise Amélineau, Jóhannis Danielsen, Rune Dietz, Kyle Elliott, Kjell Einar Erikstad, Igor Eulaers, Alexey Ezhov, Michelle G. Fitzsimmons, Maria Gavrilo, Elena Golubova, David Grémillet, Scott Hatch, Nicholas P. Huffeldt, Dariusz Jakubas, Alexander Kitaysky, Yann Kolbeinsson, Yuri Krasnov, Svein-Håkon Lorentsen, Erlend Lorentzen, Mark L. Mallory, Benjamin Merkel, Flemming Ravn Merkel, William Montevecchi, Anders Mosbech, Bergur Olsen, Rachael A. Orben, Allison Patterson, Jennifer Provencher, Christine Plumejeaud, Isabeau Pratte, Tone Kristin Reiertsen, Heather Renner, Nora Rojek, Marc Romano, Hallvard Strøm, Geir Helge Systad, Akinori Takahashi, Jean-Baptiste Thiebot, Thorkell Lindberg Thórarinsson, Alexis P. Will, Katarzyna Wojczulanis-Jakubas, Paco Bustamante, Jérôme Fort doi  openurl
  Title Seasonal variation of mercury contamination in Arctic seabirds: A pan-Arctic assessment Type Journal
  Year 2021 Publication Science of The Total Environment Abbreviated Journal  
  Volume 750 Issue Pages 142201  
  Keywords Feathers Metal Polar Seasonal variation Top predators  
  Abstract Mercury (Hg) is a natural trace element found in high concentrations in top predators, including Arctic seabirds. Most current knowledge about Hg concentrations in Arctic seabirds relates to exposure during the summer breeding period when researchers can easily access seabirds at colonies. However, the few studies focused on winter have shown higher Hg concentrations during the non-breeding period than breeding period in several tissues. Hence, improving knowledge about Hg exposure during the non-breeding period is crucial to understanding the threats and risks encountered by these species year-round. We used feathers of nine migratory alcid species occurring at high latitudes to study bird Hg exposure during both the breeding and non-breeding periods. Overall, Hg concentrations during the non-breeding period were ~3 times higher than during the breeding period. In addition, spatial differences were apparent within and between the Atlantic and Pacific regions. While Hg concentrations during the non-breeding period were ~9 times and ~3 times higher than during the breeding period for the West and East Atlantic respectively, Hg concentrations in the Pacific during the non-breeding period were only ~1.7 times higher than during the breeding period. In addition, individual Hg concentrations during the non-breeding period for most of the seabird colonies were above 5 μg g−1 dry weight (dw), which is considered to be the threshold at which deleterious effects are observed, suggesting that some breeding populations might be vulnerable to non-breeding Hg exposure. Since wintering area locations, and migration routes may influence seasonal Hg concentrations, it is crucial to improve our knowledge about spatial ecotoxicology to fully understand the risks associated with Hg contamination in Arctic seabirds.  
  Programme 388  
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  ISSN (down) 0048-9697 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8026  
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Author Ross N. Cuthbert, Zarah Pattison, Nigel G. Taylor, Laura Verbrugge, Christophe Diagne, Danish A. Ahmed, Boris Leroy, Elena Angulo, Elizabeta Briski, César Capinha, Jane A. Catford, Tatenda Dalu, Franz Essl, Rodolphe E. Gozlan, Phillip J. Haubrock, Melina Kourantidou, Andrew M. Kramer, David Renault, Ryan J. Wasserman, Franck Courchamp doi  openurl
  Title Global economic costs of aquatic invasive alien species Type Journal
  Year 2021 Publication Science of The Total Environment Abbreviated Journal  
  Volume 775 Issue Pages 145238  
  Keywords Brackish Freshwater Habitat biases InvaCost Marine Monetary impact  
  Abstract Much research effort has been invested in understanding ecological impacts of invasive alien species (IAS) across ecosystems and taxonomic groups, but empirical studies about economic effects lack synthesis. Using a comprehensive global database, we determine patterns and trends in economic costs of aquatic IAS by examining: (i) the distribution of these costs across taxa, geographic regions and cost types; (ii) the temporal dynamics of global costs; and (iii) knowledge gaps, especially compared to terrestrial IAS. Based on the costs recorded from the existing literature, the global cost of aquatic IAS conservatively summed to US$345 billion, with the majority attributed to invertebrates (62%), followed by vertebrates (28%), then plants (6%). The largest costs were reported in North America (48%) and Asia (13%), and were principally a result of resource damages (74%); only 6% of recorded costs were from management. The magnitude and number of reported costs were highest in the United States of America and for semi-aquatic taxa. Many countries and known aquatic alien species had no reported costs, especially in Africa and Asia. Accordingly, a network analysis revealed limited connectivity among countries, indicating disparate cost reporting. Aquatic IAS costs have increased in recent decades by several orders of magnitude, reaching at least US$23 billion in 2020. Costs are likely considerably underrepresented compared to terrestrial IAS; only 5% of reported costs were from aquatic species, despite 26% of known invaders being aquatic. Additionally, only 1% of aquatic invasion costs were from marine species. Costs of aquatic IAS are thus substantial, but likely underreported. Costs have increased over time and are expected to continue rising with future invasions. We urge increased and improved cost reporting by managers, practitioners and researchers to reduce knowledge gaps. Few costs are proactive investments; increased management spending is urgently needed to prevent and limit current and future aquatic IAS damages.  
  Programme 136  
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  ISSN (down) 0048-9697 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8089  
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Author Christopher Burot, Rémi Amiraux, Patricia Bonin, Sophie Guasco, Marcel Babin, Fabien Joux, Dominique Marie, Laure Vilgrain, Hermann J. Heipieper, Jean-François Rontani doi  openurl
  Title Viability and stress state of bacteria associated with primary production or zooplankton-derived suspended particulate matter in summer along a transect in Baffin Bay (Arctic Ocean) Type Journal
  Year 2021 Publication Science of The Total Environment Abbreviated Journal  
  Volume 770 Issue Pages 145252  
  Keywords Bacterial viability EPS isomerase Micro- and macro-zooplankton Salinity stress Sea ice algae  
  Abstract In the framework of the GreenEdge Project (whose the general objective is to understand the dynamic of the phytoplankton spring bloom in Arctic Ocean), lipid composition and viability and stress state of bacteria were monitored in sea ice and suspended particulate matter (SPM) samples collected in 2016 along a transect from sea ice to open water in Baffin Bay (Arctic Ocean). Lipid analyses confirmed the dominance of diatoms in the bottommost layer of ice and suggested (i) the presence of a strong proportion of micro-zooplankton in SPM samples collected at the western ice covered St 403 and St 409 and (ii) a high proportion of macro-zooplankton (copepods) in SPM samples collected at the eastern ice covered St 413 and open water St 418. The use of the propidium monoazide (PMA) method allowed to show a high bacterial mortality in sea ice and in SPM material collected in shallower waters at St 409 and St 418. This mortality was attributed to the release of bactericidal free fatty acids by sympagic diatoms under the effect of light stress. A strong cis-trans isomerization of bacterial MUFAs was observed in the deeper SPM samples collected at the St 403 and St 409. It was attributed to the ingestion of bacteria stressed by salinity in brine channels of ice by sympagic bacterivorous microzooplankton (ciliates) incorporating trans fatty acids of their preys before to be released in the water column during melting. The high trans/cis ratios also observed in SPM samples collected in the shallower waters at St 413 and St 418 suggest the presence of positively or neutrally buoyant extracellular polymeric substances (EPS)-rich particles retained in sea ice and discharged (with bacteria stressed by salinity) in seawater after the initial release of algal biomass. Such EPS particles, which are generally considered as ideal vectors for bacterial horizontal distribution in the Arctic, appeared to contain a high proportion of dead and non-growing bacteria.  
  Programme 1164  
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  ISSN (down) 0048-9697 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8253  
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Author Marina Renedo, Zoyne Pedrero, David Amouroux, Yves Cherel, Paco Bustamante doi  openurl
  Title Mercury isotopes of key tissues document mercury metabolic processes in seabirds Type Journal
  Year 2021 Publication Chemosphere Abbreviated Journal  
  Volume 263 Issue Pages 127777  
  Keywords Demethylation Detoxification Metabolism Methylmercury Moult  
  Abstract Seabirds accumulate significant amounts of mercury (Hg) due to their long-life span together with their medium to high trophic position in marine food webs. Hg speciation and Hg isotopic analyses of total Hg in different tissues (pectoral muscles, liver, brain, kidneys, blood and feathers) were assessed to investigate their detoxification mechanisms. Three species with contrasted ecological characteristics were studied: the Antarctic prion (zooplankton feeder), the white-chinned petrel (pelagic generalist consumer) and the southern giant petrel (scavenger on seabirds and marine mammals). The difference of mass-dependent fractionation (MDF, δ202Hg) values between liver and muscles (up to 0.94 ‰) in all three seabirds strongly suggests hepatic demethylation of the isotopically lighter methylmercury (MeHg) and subsequent redistribution of the isotopically heavier fraction of MeHg towards the muscles. Similarly, higher δ202Hg values in feathers (up to 1.88 ‰) relative to muscles and higher proportion of MeHg in feathers (94–97%) than muscles (30–70%) likely indicate potential MeHg demethylation in muscle and preferential excretion of MeHg (isotopically heavier) in the growing feathers during moult. The extents of these key detoxification processes were strongly dependent on the species-specific detoxification strategies and levels of dietary MeHg exposure. We also found higher mass-independent fractionation (MIF, Δ199Hg) values in feathers relative to internal tissues, possibly due to different integration times of Hg exposure between permanently active organs and inert tissues as feathers. Hg isotope variations reported in this study show evidence of detoxification processes in seabirds and propose a powerful approach for deep investigation of the Hg metabolic processes in seabirds.  
  Programme 109  
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  Series Volume Series Issue Edition  
  ISSN (down) 0045-6535 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8084  
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Author W. J. Sydeman, D. S. Schoeman, S. A. Thompson, B. A. Hoover, M. García-Reyes, F. Daunt, P. Agnew, T. Anker-Nilssen, C. Barbraud, R. Barrett, P. H. Becker, E. Bell, P. D. Boersma, S. Bouwhuis, B. Cannell, R. J. M. Crawford, P. Dann, K. Delord, G. Elliott, K. E. Erikstad, E. Flint, R. W. Furness, M. P. Harris, S. Hatch, K. Hilwig, J. T. Hinke, J. Jahncke, J. A. Mills, T. K. Reiertsen, H. Renner, R. B. Sherley, C. Surman, G. Taylor, J. A. Thayer, P. N. Trathan, E. Velarde, K. Walker, S. Wanless, P. Warzybok, Y. Watanuki doi  openurl
  Title Hemispheric asymmetry in ocean change and the productivity of ecosystem sentinels Type Journal
  Year 2021 Publication Science Abbreviated Journal  
  Volume 372 Issue 6545 Pages 980-983  
  Keywords  
  Abstract Sampling seabirds The vastness of the worlds' oceans makes them difficult to monitor. Seabirds that forage and breed across oceans globally have been recognized as sentinels of ocean health. Sydeman et al. looked across seabird species of both the Northern and Southern Hemispheres and found varying patterns. Northern Hemisphere species exhibited greater signs of stress and reduced breeding success, indicative of low fish resources. Southern Hemisphere species showed less impact on reproductive output, suggesting that the fish populations there have thus far been less disturbed. The differences across hemispheres indicate different strategies for conservation, with active recovery needed in the north and enhanced protection in the south. Science, abf1772, this issue p. 980 Climate change and other human activities are causing profound effects on marine ecosystem productivity. We show that the breeding success of seabirds is tracking hemispheric differences in ocean warming and human impacts, with the strongest effects on fish-eating, surface-foraging species in the north. Hemispheric asymmetry suggests the need for ocean management at hemispheric scales. For the north, tactical, climate-based recovery plans for forage fish resources are needed to recover seabird breeding productivity. In the south, lower-magnitude change in seabird productivity presents opportunities for strategic management approaches such as large marine protected areas to sustain food webs and maintain predator productivity. Global monitoring of seabird productivity enables the detection of ecosystem change in remote regions and contributes to our understanding of marine climate impacts on ecosystems. The breeding success of seabirds is tracking hemispheric differences in ocean warming and human impacts. The breeding success of seabirds is tracking hemispheric differences in ocean warming and human impacts.  
  Programme 109  
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  ISSN (down) 0036-8075, 1095-9203 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 7980  
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Author Laurel Kaye, Shreyas Vissapragada, Maximilian N Günther, Suzanne Aigrain, Thomas Mikal-Evans, Eric L N Jensen, Hannu Parviainen, Francisco J Pozuelos, Lyu Abe, Jack S Acton, Abdelkrim Agabi, Douglas R Alves, David R Anderson, David J Armstrong, Khalid Barkaoui, Oscar Barragán, Björn Benneke, Patricia T Boyd, Rafael Brahm, Ivan Bruni, Edward M Bryant, Matthew R Burleigh, Sarah L Casewell, David Ciardi, Ryan Cloutier, Karen A Collins, Kevin I Collins, Dennis M Conti, Ian J M Crossfield, Nicolas Crouzet, Tansu Daylan, Diana Dragomir, Georgina Dransfield, Daniel Fabrycky, Michael Fausnaugh, Gábor Fuűrész, Tianjun Gan, Samuel Gill, Michaël Gillon, Michael R Goad, Varoujan Gorjian, Michael Greklek-McKeon, Natalia Guerrero, Tristan Guillot, Emmanuël Jehin, J S Jenkins, Monika Lendl, Jacob Kamler, Stephen R Kane, John F Kielkopf, Michelle Kunimoto, Wenceslas Marie-Sainte, James McCormac, Djamel Mékarnia, Farisa Y Morales, Maximiliano Moyano, Enric Palle, Vivien Parmentier, Howard M Relles, François-Xavier Schmider, Richard P Schwarz, S Seager, Alexis M S Smith, Thiam-Guan Tan, Jake Taylor, Amaury H M J Triaud, Joseph D Twicken, Stephane Udry, J I Vines, Gavin Wang, Peter J Wheatley, Joshua N Winn doi  openurl
  Title Transit timings variations in the three-planet system: TOI-270 Type Journal
  Year 2021 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal  
  Volume 510 Issue 4 Pages 5464-5485  
  Keywords  
  Abstract We present ground- and space-based photometric observations of TOI-270 (L231-32), a system of three transiting planets consisting of one super-Earth and two sub-Neptunes discovered by TESS around a bright (K-mag = 8.25) M3V dwarf. The planets orbit near low-order mean-motion resonances (5:3 and 2:1) and are thus expected to exhibit large transit timing variations (TTVs). Following an extensive observing campaign using eight different observatories between 2018 and 2020, we now report a clear detection of TTVs for planets c and d, with amplitudes of ∼10 min and a super-period of ∼3 yr, as well as significantly refined estimates of the radii and mean orbital periods of all three planets. Dynamical modelling of the TTVs alone puts strong constraints on the mass ratio of planets c and d and on their eccentricities. When incorporating recently published constraints from radial velocity observations, we obtain masses of $M{\mathrm{b}}=1.48\pm 0.18\, M\oplus$, $M{\mathrm{c}}=6.20\pm 0.31\, M\oplus$, and $M{\mathrm{d}}=4.20\pm 0.16\, M\oplus$ for planets b, c, and d, respectively. We also detect small but significant eccentricities for all three planets : eb = 0.0167 ± 0.0084, ec = 0.0044 ± 0.0006, and ed = 0.0066 ± 0.0020. Our findings imply an Earth-like rocky composition for the inner planet, and Earth-like cores with an additional He/H2O atmosphere for the outer two. TOI-270 is now one of the best constrained systems of small transiting planets, and it remains an excellent target for atmospheric characterization.  
  Programme 1066  
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  ISSN (down) 0035-8711 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8413  
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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 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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  ISSN (down) 0034-4257 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 7997  
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Author Helena P. Baird, Seunggwan Shin, Rolf G. Oberprieler, Maurice Hullé, Philippe Vernon, Katherine L. Moon, Richard H. Adams, Duane D. McKenna, Steven L. Chown doi  openurl
  Title Fifty million years of beetle evolution along the Antarctic Polar Front Type Journal
  Year 2021 Publication Proceedings of the National Academy of Sciences Abbreviated Journal  
  Volume 118 Issue 24 Pages  
  Keywords Antarctica herbivory island biogeography paleoclimate species radiation  
  Abstract Global cooling and glacial–interglacial cycles since Antarctica’s isolation have been responsible for the diversification of the region’s marine fauna. By contrast, these same Earth system processes are thought to have played little role terrestrially, other than driving widespread extinctions. Here, we show that on islands along the Antarctic Polar Front, paleoclimatic processes have been key to diversification of one of the world’s most geographically isolated and unique groups of herbivorous beetles—Ectemnorhinini weevils. Combining phylogenomic, phylogenetic, and phylogeographic approaches, we demonstrate that these weevils colonized the sub-Antarctic islands from Africa at least 50 Ma ago and repeatedly dispersed among them. As the climate cooled from the mid-Miocene, diversification of the beetles accelerated, resulting in two species-rich clades. One of these clades specialized to feed on cryptogams, typical of the polar habitats that came to prevail under Miocene conditions yet remarkable as a food source for any beetle. This clade’s most unusual representative is a marine weevil currently undergoing further speciation. The other clade retained the more common weevil habit of feeding on angiosperms, which likely survived glaciation in isolated refugia. Diversification of Ectemnorhinini weevils occurred in synchrony with many other Antarctic radiations, including penguins and notothenioid fishes, and coincided with major environmental changes. Our results thus indicate that geo-climatically driven diversification has progressed similarly for Antarctic marine and terrestrial organisms since the Miocene, potentially constituting a general biodiversity paradigm that should be sought broadly for the region’s taxa.  
  Programme 136  
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  Series Volume Series Issue Edition  
  ISSN (down) 0027-8424, 1091-6490 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8087  
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