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Author M. Afroosa, B. Rohith, Arya Paul, Fabien Durand, Romain Bourdallé-Badie, P. V. Sreedevi, Olivier de Viron, Valérie Ballu, S. S. C. Shenoi doi  openurl
  Title Madden-Julian oscillation winds excite an intraseasonal see-saw of ocean mass that affects Earth’s polar motion Type Journal
  Year 2021 Publication Communications Earth & Environment Abbreviated Journal  
  Volume 2 Issue 1 Pages 1-8  
  Keywords Physical oceanography  
  Abstract Strong large-scale winds can relay their energy to the ocean bottom and elicit an almost immediate intraseasonal barotropic (depth independent) response in the ocean. The intense winds associated with the Madden-Julian Oscillation over the Maritime Continent generate significant intraseasonal basin-wide barotropic sea level variability in the tropical Indian Ocean. Here we show, using a numerical model and a network of in-situ bottom pressure recorders, that the concerted barotropic response of the Indian and the Pacific Ocean to these winds leads to an intraseasonal see-saw of oceanic mass in the Indo-Pacific basin. This global-scale mass shift is unexpectedly fast, as we show that the mass field of the entire Indo-Pacific basin is dynamically adjusted to Madden-Julian Oscillation in a few days. We find this large-scale ocean see-saw, induced by the Madden-Julian Oscillation, has a detectable influence on the Earth’s polar axis motion, in particular during the strong see-saw of early 2013.  
  Programme 688  
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  Series Editor (down) Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2662-4435 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8387  
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Author Petra Zemunik, Jadranka Šepić, Havu Pellikka, Leon Ćatipović, Ivica Vilibić doi  openurl
  Title Minute Sea-Level Analysis (MISELA): a high-frequency sea-level analysis global dataset Type Journal
  Year 2021 Publication Earth system science data Abbreviated Journal  
  Volume 13 Issue 8 Pages 4121-4132  
  Keywords  
  Abstract

Abstract. Sea-level observations provide information on a variety of processes occurring over different temporal and spatial scales that may contribute to coastal flooding and hazards. However, global research on sea-level extremes is restricted to hourly datasets, which prevent the quantification and analyses of processes occurring at timescales between a few minutes and a few hours. These shorter-period processes, like seiches, meteotsunamis, infragravity and coastal waves, may even dominate in low tidal basins. Therefore, a new global 1 min sea-level dataset – MISELA (Minute Sea-Level Analysis) – has been developed, encompassing quality-checked records of nonseismic sea-level oscillations at tsunami timescales (T<2 h) obtained from 331 tide-gauge sites (https://doi.org/10.14284/456, Zemunik et al., 2021b). This paper describes data quality control procedures applied to the MISELA dataset, world and regional coverage of tide-gauge sites, and lengths of time series. The dataset is appropriate for global, regional or local research of atmospherically induced high-frequency sea-level oscillations, which should be included in the overall sea-level extremes assessments.

 
  Programme 688  
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  Series Editor (down) Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1866-3508 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8392  
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Author A. Barbero, J. Savarino, R. Grilli, C. Blouzon, G. Picard, M. M. Frey, Y. Huang, N. Caillon doi  openurl
  Title New Estimation of the NOx Snow-Source on the Antarctic Plateau Type Journal
  Year 2021 Publication Journal of Geophysical Research: Atmospheres Abbreviated Journal  
  Volume 126 Issue 20 Pages e2021JD035062  
  Keywords Antarctic Plateau flux chamber nitrate photolysis snowpack emissions  
  Abstract To fully decipher the role of nitrate photolysis on the atmospheric oxidative capacity in snow-covered regions, NOx flux must be determined with more precision than existing estimates. Here, we introduce a method based on dynamic flux chamber measurements for evaluating the NOx production by photolysis of snowpack nitrate in Antarctica. Flux chamber experiments were conducted for the first time in Antarctica, at the French-Italian station Concordia, Dome C (75°06'S, 123°20’E, 3233 m a.s.l) during the 2019–2020 summer campaign. Measurements were gathered with several snow samples of different ages ranging from newly formed drifted snow to 6-year-old firn. Contrary to existing literature expectations, the daily average photolysis rate coefficient, , did not significantly vary between differently aged snow samples, suggesting that the photolabile nitrate in snow behaves as a single-family source with common photochemical properties, where a = (2.37 0.35) × 10−8 s−1 (1) has been calculated from December 10th 2019 to January 7th 2020. At Dome C summer daily average NOx flux, , based on measured NOx production rates was estimated to be (4.3 1.2) × 108 molecules cm−2 s−1, which is 1.5–7 times less than the net NOx flux observed previously above snow at Dome C using the gradient flux method. Using these results, we extrapolated an annual continental snow sourced NOx budget of 0.017 0.003 TgN y−1, 2 times the nitrogen budget, (N-budget), of the stratospheric denitrification previously estimated for Antarctica. These quantifications of nitrate photolysis using flux chamber experiments provide a road-map toward a new parameterization of the product that can improve future global and regional models of atmospheric chemistry.  
  Programme 1177  
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  Series Volume Series Issue Edition  
  ISSN 2169-8996 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8393  
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Author Yushiro Fujii, Kenji Satake, Shingo Watada, Tung-Cheng Ho doi  openurl
  Title 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  
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  Series Editor (down) 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 S. Ishino, S. Hattori, M. Legrand, Q. Chen, B. Alexander, J. Shao, J. Huang, L. Jaeglé, B. Jourdain, S. Preunkert, A. Yamada, N. Yoshida, J. Savarino doi  openurl
  Title Regional Characteristics of Atmospheric Sulfate Formation in East Antarctica Imprinted on 17O-Excess Signature Type Journal
  Year 2021 Publication Journal of Geophysical Research: Atmospheres Abbreviated Journal  
  Volume 126 Issue 6 Pages e2020JD033583  
  Keywords aerosols Antarctica isotope methanesulfonate sulfate  
  Abstract 17O-excess (Δ17O = δ17O − 0.52 × δ18O) of sulfate trapped in Antarctic ice cores has been proposed as a potential tool for assessing past oxidant chemistry, while insufficient understanding of atmospheric sulfate formation around Antarctica hampers its interpretation. To probe influences of regional specific chemistry, we compared year-round observations of Δ17O of non-sea-salt sulfate in aerosols (Δ17O(SO42−)nss) at Dome C and Dumont d'Urville, inland and coastal sites in East Antarctica, throughout the year 2011. Although Δ17O(SO42−)nss at both sites showed consistent seasonality with summer minima (∼1.0‰) and winter maxima (∼2.5‰) owing to sunlight-driven changes in the relative importance of O3 oxidation to OH and H2O2 oxidation, significant intersite differences were observed in austral spring–summer and autumn. The cooccurrence of higher Δ17O(SO42−)nss at inland (2.0‰ ± 0.1‰) than the coastal site (1.2‰ ± 0.1‰) and chemical destruction of methanesulfonate (MS–) in aerosols at inland during spring–summer (October–December), combined with the first estimated Δ17O(MS–) of ∼16‰, implies that MS– destruction produces sulfate with high Δ17O(SO42−)nss of ∼12‰. If contributing to the known postdepositional decrease of MS– in snow, this process should also cause a significant postdepositional increase in Δ17O(SO42−)nss over 1‰, that can reconcile the discrepancy between Δ17O(SO42−)nss in the atmosphere and ice. The higher Δ17O(SO42−)nss at the coastal site than inland during autumn (March–May) may be associated with oxidation process involving reactive bromine and/or sea-salt particles around the coastal region.  
  Programme 1177  
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  Series Volume Series Issue Edition  
  ISSN 2169-8996 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8412  
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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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  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8413  
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Author Christophe Barbraud, Karine Delord doi  openurl
  Title Selection against immigrants in wild seabird populations Type Journal
  Year 2021 Publication Ecology Letters Abbreviated Journal  
  Volume 24 Issue 1 Pages 84-93  
  Keywords Dispersal fitness immigrant seabirds sex-biased dispersal  
  Abstract Immigration is a major demographic parameter shaping population dynamics and is an important driver of eco-evolutionary patterns, but the fitness consequences for individuals following their settlement to a new population (immigrants) remain poorly tested in wild animal populations, particularly among long-lived species. Here we show that immigrants have a lower fitness than residents in three wild seabird populations (wandering albatross Diomedea exulans, southern fulmar Fulmarus glacialoides, snow petrel Pagodroma nivea). Across all species and during a 32-year period, immigrants made on average −9 to 29% fewer breeding attempts, had 5–31% fewer fledglings, had 2–16% lower breeding success and produced 6–46% fewer recruits. Female immigration and male residency were also favored through differences in breeding performance. We provide evidence for selection against immigrants in wild populations of long-lived species and our results are consistent with female-biased dispersal in birds being driven by asymmetric limiting resources and the competitive ability of dispersers vs. non-dispersers.  
  Programme 109  
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  Series Editor (down) Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1461-0248 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8418  
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Author Sébastien Descamps, Benjamin Merkel, Hallvard Strøm, Rémi Choquet, Harald Steen, Jérome Fort, Maria Gavrilo, David Grémillet, Dariusz Jakubas, Kurt Jerstad, Nina J. Karnovsky, Yuri V. Krasnov, Børge Moe, Jorg Welcker, Katarzyna Wojczulanis-Jakubas doi  openurl
  Title Sharing wintering grounds does not synchronize annual survival in a high Arctic seabird, the little auk Type Journal
  Year 2021 Publication Marine Ecology Progress Series Abbreviated Journal  
  Volume 676 Issue Pages 233-242  
  Keywords Alle alle Capture-mark-recapture Geolocator Migration Non-breeding distribution Synchrony  
  Abstract Sharing the same wintering grounds by avian populations breeding in various areas may synchronize fluctuations in vital rates, which could increase the risk of extinction. Here, by combining multi-colony tracking with long-term capture-recapture data, we studied the winter distribution and annual survival of the most numerous Arctic seabird, the little auk Alle alle. We assessed whether little auks from different breeding populations in Svalbard and Franz Josef Land use the same wintering grounds and if this leads to synchronized survival. Our results indicate that birds from the Svalbard colonies shared similar wintering grounds, although differences existed in the proportion of birds from each colony using the different areas. Little auks from Franz Josef Land generally spent the winter in a separate area, but some individuals wintered in the Iceland Sea with Svalbard populations. Survival data from 3 Svalbard colonies collected in 2005-2018 indicated that sharing wintering grounds did not synchronize little auk annual survival rates. However, it is clear that the Iceland Sea is an important wintering area for little auks, and environmental changes in this area could have widespread impacts on many populations.  
  Programme 388  
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  Series Volume Series Issue Edition  
  ISSN 0171-8630, 1616-1599 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8419  
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Author María José Frugone, Theresa L. Cole, María Eugenia López, Gemma Clucas, Pável Matos-Maraví, Nicolás A. Lois, Pierre Pistorius, Francesco Bonadonna, Phil Trathan, Andrea Polanowski, Barbara Wienecke, Andrea Raya-Rey, Klemens Pütz, Antje Steinfurth, Ke Bi, Cynthia Y. Wang-Claypool, Jonathan M. Waters, Rauri C. K. Bowie, Elie Poulin, Juliana A. Vianna doi  openurl
  Title Taxonomy based on limited genomic markers may underestimate species diversity of rockhopper penguins and threaten their conservation Type Journal
  Year 2021 Publication Diversity and Distributions Abbreviated Journal  
  Volume 27 Issue 11 Pages 2277-2296  
  Keywords Eudyptes genomics rockhopper penguins species delimitation  
  Abstract Aim Delimiting recently diverged species is challenging. During speciation, genetic differentiation may be distributed unevenly across the genome, as different genomic regions can be subject to different selective pressures and evolutionary histories. Reliance on limited numbers of genetic markers that may be underpowered can make species delimitation even more challenging, potentially resulting in taxonomic inconsistencies. Rockhopper penguins of the genus Eudyptes comprise three broadly recognized taxa: northern (E. moseleyi), southern (E. chrysocome) and eastern rockhopper (E. filholi). Their taxonomic status has been controversial for decades, with researchers disagreeing about whether E. chrysocome and E. filholi are distinct species or conspecific. Our goal is to evaluate genome-wide patterns of divergence to evaluate genetic differentiation and species delimitation in rockhopper penguins, and to assess which mechanisms may underlie previous discordance among nuclear versus mitochondrial analyses. Location Sub-Antarctic and temperate coastal regions of the Southern Hemisphere. Methods We generated reduced-representation genomic libraries using double digest restriction-site associated DNA (ddRAD) sequencing to evaluate genetic differentiation, contemporary migration rates and admixture among colonies of rockhopper penguins. Results The extent of genetic differentiation among the three taxa was consistently higher than population-level genetic differentiation found within these and other penguin species. There was no evidence of admixture among the three taxa, suggesting the absence of ongoing gene flow among them. Species delimitation analyses based on molecular data, along with other lines of evidence, provide strong support for the taxonomic distinction of three species of rockhopper penguins. Main conclusions Our results provide strong support for the existence of three distinct species of rockhopper penguins. The recognition of this taxonomic diversity is crucial for the management and conservation of this widely distributed species group. This study illustrates that widespread dispersive seabird lineages lacking obvious morphological differences may nevertheless have complex evolutionary histories and comprise cryptic species diversity.  
  Programme 354  
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  Series Volume Series Issue Edition  
  ISSN 1472-4642 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8421  
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Author Armelle Decaulne, Najat Bhiry, Janie Faucher-Roy, Clara Pelletier Boily doi  openurl
  Title The development of Kangiqsualujjuaq and the threat of snow avalanches in a permafrost degradation context, Nunavik, Canada Type Journal
  Year 2021 Publication Espace populations sociétés. Space populations societies Abbreviated Journal  
  Volume Issue 2020/3-2021/1 Pages  
  Keywords active layer Canada demographic growth Nordic village slopes snow avalanches  
  Abstract Slope processes are active in the rolling plateau landscapes of Nunavik, Northern Québec, Canada. There are a few short but very steep escarpments in this region. On January 1st, 1999 a powerful snow avalanche struck Kangiqsualujjuaq, one of the 14 Inuit villages in Nunavik. Nine people died and 25 were injured. This village and its surrounding are located within a glacial valley, in a periglacial environment. There is significant population growth, as well as in the other villages in Nunavik. As early as 1999-2000, there was a significant spatial reorganization of the village's infrastructures to avoid the impact of other snow-avalanche events. The main objective of this paper is to examine the village expansion in response to snow-avalanche process and population growth, within an area constrained with permafrost thawing and steep slopes. From naturalist geomorphologic methods, written sources such as archive documents and aerial photographs, the results show that slopes above Kangiqsualujjuaq are prone to release snow avalanches during blizzards from uncommon directions, and that the newly built housing may be at risk in some places, due to the conjunction of snow avalanches and permafrost thawing.  
  Programme 1148  
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  Series Volume Series Issue Edition  
  ISSN 0755-7809 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8423  
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