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Author Charles Amory, Christoph Kittel, Louis Le Toumelin, Cécile Agosta, Alison Delhasse, Vincent Favier, Xavier Fettweis doi  openurl
  Title 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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  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 (down) 1991-959X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8428  
Permanent link to this record
 

 
Author Ole Richter, David E. Gwyther, Benjamin K. Galton-Fenzi, Kaitlin A. Naughten doi  openurl
  Title The Whole Antarctic Ocean Model (WAOM v1.0): development and evaluation Type Journal
  Year 2022 Publication Geoscientific Model Development Abbreviated Journal  
  Volume 15 Issue 2 Pages 617-647  
  Keywords  
  Abstract The Regional Ocean Modeling System (ROMS), including an ice shelf component, has been applied on a circum-Antarctic domain to derive estimates of ice shelf basal melting. Significant improvements made compared to previous models of this scale are the inclusion of tides and a horizontal spatial resolution of 2 km, which is sufficient to resolve on-shelf heat transport by bathymetric troughs and eddy-scale circulation. We run the model with ocean–atmosphere–sea ice conditions from the year 2007 to represent nominal present-day climate. We force the ocean surface with buoyancy fluxes derived from sea ice concentration observations and wind stress from ERA-Interim atmospheric reanalysis. Boundary conditions are derived from the ECCO2 ocean state estimate; tides are incorporated as sea surface height and barotropic currents at the open boundary. We evaluate model results using satellite-derived estimates of ice shelf melting and established compilations of ocean hydrography. The Whole Antarctic Ocean Model (WAOM v1.0) qualitatively captures the broad scale difference between warm and cold regimes as well as many of the known characteristics of regional ice–ocean interaction. We identify a cold bias for some warm-water ice shelves and a lack of high-salinity shelf water (HSSW) formation. We conclude that further calibration and development of our approach are justified. At its current state, the model is ideal for addressing specific, process-oriented questions, e.g. related to tide-driven ice shelf melting at large scales.  
  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 (down) 1991-959X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8597  
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Author Nairita Pal, Kristin N. Barton, Mark R. Petersen, Steven R. Brus, Darren Engwirda, Brian K. Arbic, Andrew F. Roberts, Joannes J. Westerink, Damrongsak Wirasaet doi  openurl
  Title Barotropic tides in MPAS-Ocean (E3SM V2): impact of ice shelf cavities Type Journal
  Year 2023 Publication Geoscientific Model Development Abbreviated Journal  
  Volume 16 Issue 4 Pages 1297-1314  
  Keywords  
  Abstract Oceanic tides are seldom represented in Earth system models (ESMs) owing to the need for high horizontal resolution to accurately represent the associated barotropic waves close to coasts. This paper presents results of tides implemented in the Model for Prediction Across Scales–Ocean or MPAS-Ocean, which is the ocean component within the U.S. Department of Energy developed Energy Exascale Earth System Model (E3SM). MPAS-Ocean circumvents the limitation of low resolution using unstructured global meshing. We are at this stage simulating the largest semidiurnal (M2, S2, N2) and diurnal (K1, O1) tidal constituents in a single-layer version of MPAS-O. First, we show that the tidal constituents calculated using MPAS-Ocean closely agree with the results of the global tidal prediction model TPXO8 when suitably tuned topographic wave drag and bottom drag coefficients are employed. Thereafter, we present the sensitivity of global tidal evolution due to the presence of Antarctic ice shelf cavities. The effect of ice shelves on the amplitude and phase of tidal constituents are presented. Lower values of complex errors (with respect to TPXO8 results) for the M2 tidal constituents are observed when the ice shelf is added in the simulations, with particularly strong improvement in the Southern Ocean. Our work points towards future research with varying Antarctic ice shelf geometries and sea ice coupling that might lead to better comparison and prediction of tides and thus better prediction of sea-level rise and also the future climate variability.  
  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 (down) 1991-959X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8619  
Permanent link to this record
 

 
Author Pengyang Song, Dmitry Sidorenko, Patrick Scholz, Maik Thomas, Gerrit Lohmann doi  openurl
  Title The tidal effects in the Finite-volumE Sea ice–Ocean Model (FESOM2.1): a comparison between parameterised tidal mixing and explicit tidal forcing Type Journal
  Year 2023 Publication Geoscientific Model Development Abbreviated Journal  
  Volume 16 Issue 1 Pages 383-405  
  Keywords  
  Abstract Tides are proved to have a significant effect on the ocean and climate. Previous modelling research either adds a tidal mixing parameterisation or an explicit tidal forcing to the ocean models. However, no research compares the two approaches in the same framework. Here we implement both schemes in a general ocean circulation model and assess both methods by comparing the results. The aspects for comparison involve hydrography, sea ice, meridional overturning circulation (MOC), vertical diffusivity, barotropic streamfunction and energy diagnostics. We conclude that although the mesh resolution is poor in resolving internal tides in most mid-latitude and shelf-break areas, explicit tidal forcing still shows stronger tidal mixing at the Kuril–Aleutian Ridge and the Indonesian Archipelago than the tidal mixing parameterisation. Beyond that, the explicit tidal forcing method leads to a stronger upper cell of the Atlantic MOC by enhancing the Pacific MOC and the Indonesian Throughflow. Meanwhile, the tidal mixing parameterisation leads to a stronger lower cell of the Atlantic MOC due to the tidal mixing in deep oceans. Both methods maintain the Antarctic Circumpolar Current at a higher level than the control run by increasing the meridional density gradient. We also show several phenomena that are not considered in the tidal mixing parameterisation, for example, the changing of energy budgets in the ocean system, the bottom drag induced mixing on the continental shelves and the sea ice transport by tidal motions. Due to the limit of computational capacity, an internal-tide-resolving simulation is not feasible for climate studies. However, a high-resolution short-term tidal simulation is still required to improve parameters and parameterisation schemes in climate studies.  
  Programme 688  
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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 (down) 1991-959X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8643  
Permanent link to this record
 

 
Author Maj Emilie, Vaté Virginie openurl 
  Title Au-delà de l'Oural.., La recherche anthropologique en Sibérie Type Journal Article
  Year 2009 Publication La revue pour l’histoire du CNRS Abbreviated Journal  
  Volume Issue Pages 41  
  Keywords  
  Abstract An article about the anthropological research about Siberia in France since the bigenning of the XX century. website of the journal: http://histoire-cnrs.revues.org/  
  Programme 1024  
  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 (down) 1955-2408 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 5914  
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Author Carole Ferret openurl 
  Title Leurrer la nature : quelques exemples de manipulation des bêtes en Asie intérieure Type Journal Article
  Year 2013 Publication Cahiers d’anthropologie sociale Abbreviated Journal  
  Volume Issue Pages p. 72-96  
  Keywords  
  Abstract Leurrer la nature : quelques exemples de manipulation des bêtes en Asie intérieure Leurrer est une manipulation de type « faire croire pour faire agir ». Son efficacité se fonde sur une tromperie des sens. Elle implique que le sujet leurrant suppose une forme d’intentionnalité chez l’objet leurré. Outre la chasse au vol, domaine primordial du leurre, l’élevage pastoral en Sibérie et en Asie centrale nous fournit plusieurs exemples de telles manipulations. Ainsi, la méthode de la « sucée » employée pour la traite des femelles, avec participation du petit, montre que la mulsion n’est pas une simple opération de prélèvement, mais plutôt une manipulation de la femelle qui, abusée par la vue, l’odeur et le toucher de son petit, consent à donner son lait. De même, plusieurs procédés olfactifs, gustatifs, visuels, tactiles et auditifs (recouvrir le jeune adopté par la peau du petit mort, l’enduire de sel, des sécrétions vaginales de la mère, jouer de la musique, etc.) sont utilisés cas de refus d’allaitement de son petit ou d’adoption d’un autre. Pour le gardiennage, les huchements d’appel et de conduite des troupeaux ne répondent que partiellement à la logique du leurre. Si quelques-uns sont motivés dans leur forme par l’imitation du cri animal, il s’avère que, dans l’émission de ces huchements, les bergers apparaissent peu soucieux de parfaire cette imitation et leur efficacité se base surtout sur la répétition, créant un conditionnement. D’autres leurres, enfin, sont utilisés dans la chasse ou pour effaroucher les prédateurs du bétail, tels que les épouvantails à loups.

Abstract
Luring nature: some examples of cattle handling in Inner Asia
Luring is a particular type of action, a manipulation which consists in “making the other believe and so to act.” Its effectiveness is based on a deception of senses. It implies that the luring subject assumes that the lured object has a form of intentionality. Besides hawking, initial field of the lure, Siberian and Central Asian pastoralism gives us several examples of such manipulations. The “suckling” technique used to milk females with the participation of the foal, the calf or the young camel, shows that the milking is not a simple extracting operation, but rather a manipulation of the female: abused by her senses as she sees, hears, touches, smells her young, she agrees to give her milk. Similarly, several techniques involving sight, smell, taste, touch and hearing (covering the young with the skin of the dead one, coating him with salt, with vaginal secretion of the female, playing music, etc.) are used when the female rejects her young or when breeders wants her to adopt another one. For herding, the vocalizations (“huchements” in French) used by shepherds to call animals and to control herds’ movements respond only partially to the logic of the lure. Some are motivated by the imitation of the animal’s cry, but it turns out that shepherds while uttering these vocalizations don’t endeavour to perfect this imitation. The effectiveness of these sounds is mainly based on repetition, conditioning animal behaviour. Other lures, finally, are used in hunting or scaring livestock predators such as scarecrows against wolves.
 
  Programme 1057  
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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 (down) 1951-5030 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 4855  
Permanent link to this record
 

 
Author Elena Dobrică, Ryan C. Ogliore, Cécile Engrand, Kazuhide Nagashima, Adrian J. Brearley doi  openurl
  Title Mineralogy and oxygen isotope systematics of magnetite grains and a magnetite-dolomite assemblage in hydrated fine-grained Antarctic micrometeorites Type Journal
  Year 2019 Publication Meteoritics & Planetary Science Abbreviated Journal  
  Volume 54 Issue 9 Pages 1973-1989  
  Keywords  
  Abstract We report the mineralogy and texture of magnetite grains, a magnetite-dolomite assemblage, and the adjacent mineral phases in five hydrated fine-grained Antarctic micrometeorites (H-FgMMs). Additionally, we measured the oxygen isotopic composition of magnetite grains and a magnetite-dolomite assemblage in these samples. Our mineralogical study shows that the secondary phases identified in H-FgMMs have similar textures and chemical compositions to those described previously in other primitive solar system materials, such as carbonaceous chondrites. However, the oxygen isotopic compositions of magnetite in H-FgMMs span a range of ∆17O values from +1.3‰ to +4.2‰, which is intermediate between magnetites measured in carbonaceous and ordinary chondrites (CCs and OCs). The δ18O values of magnetites in one H-FgMM have a 27‰ mass-dependent spread in a single 100 × 200 μm particle, indicating that there was a localized control of the fluid composition, probably due to a low water-to-rock mass ratio. The ∆17O values of magnetite indicate that H-FgMMs sampled a different aqueous fluid than ordinary and carbonaceous chondrites, implying that the source of H-FgMMs is probably distinct from the asteroidal source of CCs and OCs. Additionally, we analyzed the oxygen isotopic composition of a magnetite-dolomite assemblage in one of the H-FgMMs (sample 03-36-46) to investigate the temperature at which these minerals coprecipitated. We have used the oxygen isotope fractionation between the coexisting magnetite and dolomite to infer a precipitation temperature between 160 and 280 °C for this sample. This alteration temperature is 100–200 °C warmer than that determined from a calcite-magnetite assemblage from the CR2 chondrite Al Rais, but similar to the estimated temperature of aqueous alteration for unequilibrated OCs, CIs, and CMs. This suggests that the sample 03-36-46 could come from a parent body that was large enough to attain temperatures as high as the OCs, CIs, and CMs, which implies an asteroidal origin for this particular H-FgMM.  
  Programme 1120  
  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 (down) 1945-5100 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7898  
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Author Y. Quesnel, W. Zylberman, P. Rochette, M. Uehara, J. Gattacceca, G. R. Osinski, P. Dussouillez, C. Lepaulard, C. Champollion doi  openurl
  Title Geophysical signature of the Tunnunik impact structure, Northwest Territories, Canada Type Journal
  Year 2020 Publication Meteoritics & Planetary Science Abbreviated Journal  
  Volume 55 Issue 3 Pages 480-495  
  Keywords  
  Abstract In 2011, the discovery of shatter cones confirmed the 28 km diameter Tunnunik complex impact structure, Northwest Territories, Canada. This study presents the first results of ground-based electromagnetic, gravimetric, and magnetic surveys over this impact structure. Its central area is characterized by a 10 km wide negative gravity anomaly of about 3 mGal amplitude, roughly corresponding to the area of shatter cones, and associated with a positive magnetic field anomaly of 120 nT amplitude and 3 km wavelength. The latter correlates well with the location of the deepest uplifted strata, an impact-tilted Proterozoic dolomite layer of the Shaler Supergroup exposed near the center of the structure and intruded by dolerite dykes. Locally, electromagnetic field data unveil a conductive superficial formation which corresponds to an 80–100 m thick sand layer covering the impact structure. Based on the measurements of magnetic properties of rock samples, we model the source of the magnetic anomaly as the magnetic sediments of the Shaler Supergroup combined with a core of uplifted crystalline basement with enhanced magnetization. More classically, the low gravity signature is attributed to a reduction in density measured on the brecciated target rocks and to the isolated sand formations. However, the present-day fractured zone does not extend deeper than 1 km in our model, indicating a possible 1.5 km of erosion since the time of impact, about 430 Ma ago.  
  Programme 1139  
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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 (down) 1945-5100 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8266  
Permanent link to this record
 

 
Author Y. Klanten, R.-M. Couture, K. S. Christoffersen, W. F. Vincent, D. Antoniades doi  openurl
  Title Oxygen Depletion in Arctic Lakes: Circumpolar Trends, Biogeochemical Processes, and Implications of Climate Change Type Journal
  Year 2023 Publication Global Biogeochemical Cycles Abbreviated Journal  
  Volume 37 Issue 5 Pages e2022GB007616  
  Keywords Arctic lakes biochemical processes climate change dissolved oxygen freshwater meta-analysis  
  Abstract Polar amplification of climate change has the potential to cause large-scale shifts in the dissolved oxygen (DO) dynamics of Arctic lakes, with implications for fish survival, greenhouse gas production, and drinking water quality. While DO is also a sentinel of environmental changes of physical, chemical, and biological nature (e.g., ice cover, temperature, dissolved organic carbon, photosynthesis, and respiration), no synthesis exists of current knowledge of DO dynamics across the diverse freshwater systems of the Arctic. We thus conducted a systematic review of the literature that yielded DO data from 167 sites north of the Subarctic limit (based on vegetation zones), spanning 76 years and including 40 sites with time series. The compilation revealed insufficient observations for adequate representativeness of oxygen dynamics over Arctic ecosystem gradients. We described the main processes controlling DO budgets of Arctic lakes and tested relationships of summer oxygen depletion with maximum depth and latitude. The meta-analysis showed that most sites with low O2 concentrations were shallow (<10 m) and situated toward the southern end of the latitudinal gradient. Permanently stratified lakes with deep, perennially anoxic basins were located toward the northern end of the gradient. By way of a conceptual model, we identified the direct and indirect drivers and mechanisms that lead to changes in oxygen budgets in the context of the warming Arctic. This comprehensive update on available data allowed us to suggest future research directions and recommend the use of moored instruments for continuous all-season observations, combined with modeling, remote sensing, and paleo-reconstructions.  
  Programme 1042  
  Campaign  
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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 (down) 1944-9224 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8633  
Permanent link to this record
 

 
Author A. T. Ringler, R. E. Anthony, R. C. Aster, C. J. Ammon, S. Arrowsmith, H. Benz, C. Ebeling, A. Frassetto, W.-Y. Kim, P. Koelemeijer, H. C. P. Lau, V. Lekić, J. P. Montagner, P. G. Richards, D. P. Schaff, M. Vallée, W. Yeck doi  openurl
  Title Achievements and Prospects of Global Broadband Seismographic Networks After 30 Years of Continuous Geophysical Observations Type Journal
  Year 2022 Publication Reviews of Geophysics Abbreviated Journal  
  Volume 60 Issue 3 Pages e2021RG000749  
  Keywords  
  Abstract Global seismographic networks (GSNs) emerged during the late nineteenth and early twentieth centuries, facilitated by seminal international developments in theory, technology, instrumentation, and data exchange. The mid- to late-twentieth century saw the creation of the World-Wide Standardized Seismographic Network (1961) and International Deployment of Accelerometers (1976), which advanced global geographic coverage as seismometer bandwidth increased greatly allowing for the recording of the Earth's principal seismic spectrum. The modern era of global observations and rapid data access began during the 1980s, and notably included the inception of the GEOSCOPE initiative (1982) and GSN (1988). Through continual improvements, GEOSCOPE and the GSN have realized near-real time recording of ground motion with state-of-art data quality, dynamic range, and timing precision to encompass 180 seismic stations, many in very remote locations. Data from GSNs are increasingly integrated with other geophysical data (e.g., space geodesy, infrasound and Interferometric Synthetic Aperture Radar). Globally distributed seismic data are critical to resolving crust, mantle, and core structure; illuminating features of the plate tectonic and mantle convection system; rapid characterization of earthquakes; identification of potential tsunamis; global nuclear test verification; and provide sensitive proxies for environmental changes. As the global geosciences community continues to advance our understanding of Earth structure and processes controlling elastic wave propagation, GSN infrastructure offers a springboard to realize increasingly multi-instrument geophysical observatories. Here, we review the historical, scientific, and monitoring heritage of GSNs, summarize key discoveries, and discuss future associated opportunities for Earth Science.  
  Programme 133  
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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 (down) 1944-9208 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8559  
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