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Author doi  openurl
  Title Echo occurrence in the southern polar ionosphere for the SuperDARN Dome C East and Dome C North radars Type Journal
  Year 2021 Publication Polar Science Abbreviated Journal  
  Volume 28 Issue Pages 100684  
  Keywords Echo occurrence IRI model Polar cap radars Ray-tracing  
  Abstract In this paper, echo occurrence rates for the Dome C East (DCE) and the new Dome C North (DCN) radars are studied. We report the ionospheric and ground scatter echo occurrence rates for selected periods around equinoxes and solstices in the final part of the solar cycle XXIV. The occurrence maps built in Altitude Adjusted Corrected Geomagnetic latitude and Magnetic Local Time coordinates show peculiar patterns highly variable with season. The comparisons of the radar observations with the International Reference Ionosphere model electron density and with ray tracing simulations allow us to explain the major features of observed patterns in terms of electron density variations. The study shows the great potential of the DCE and DCN radar combination to the Super Dual Auroral Radar Network (SuperDARN) convection mapping in terms of monitoring key regions of the high-latitude ionosphere critical for understanding of the magnetospheric dynamics.  
  Programme 312  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1873-9652 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8020  
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Author doi  openurl
  Title Impact of socio-economic traditions on current tobacco and tea addictions (Siberia 17th to 20th century) Type Journal
  Year 2021 Publication Medrxiv Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract Objective To investigate how tobacco and tea spread among virgin populations and how the first addictions have subsequently influenced the behavior of present-day populations. Design Retrospective observational study using data from frozen burials and levels of theobromine, theophylline, caffeine, nicotine, and cotinine measured in hair samples from frozen bodies of autochthonous people. Confrontation of the results with new ethnobotanical, historical and cultural data from the past and with present day epidemiological data from the same region. Setting Eastern Siberia (Yakutia) from the contact with Europeans (17th century) to the assimilation of people into Russian society (19th century). Participants 47 frozen bodies of autochthonous people from eastern Siberia and a review of present-day populations from Yakutia Intervention Levels of theobromine, theophylline, caffeine, nicotine, and cotinine were measured in hair samples. Along with the collection of cultural data associated with the bodies, potential comorbidities were investigated. Main outcome measure We combined LC-HRMS and LC-MS/MS tools for toxicological investigations in hair and we assessed the association between xenobiotic concentrations and geography using several permutation-based methods to infer the economic circuits of tobacco and tea. Comparison of the results obtained with ethno-botanical analyses allowed to identify the products from which the metabolites were derived. Results Hair levels of theobromine, theophylline and caffeine vary with the type of beverage consumed: green, black or local herbal teas. At the beginning of our study period, a few heavy consumers of tobacco were found among light or passive consumers. Tobacco-related co-morbidities began to be recorded one century after contact with Europeans. Heavy tea users were only found from the 19th century and the heaviest users of the two substances date from this century. After the first contact, teas were widely consumed as beverages and medicines but also for shamanic reasons. Economic factors, fashion and social and family contacts seem to have played a decisive role in tobacco consumption very early on. Conclusion Epidemiological characteristics of present-day Yakutia suggest that the high prevalence of smokers and tea consumers, the prevalence of female smokers and tobacco use in the north, find their origins in the diffusion phenomena of the 18th and 19th century. Behavioral evolution governed the process of substance integration and was determinant for the continuity of use of these substances over a long period of time.  
  Programme 1038  
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  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7952  
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Author doi  openurl
  Title Contrasting Spatial and Seasonal Trends of Methylmercury Exposure Pathways of Arctic Seabirds: Combination of Large-Scale Tracking and Stable Isotopic Approaches Type Journal
  Year 2021 Publication Environmental Science & Technology Abbreviated Journal  
  Volume 54 Issue 21 Pages 13619-13629  
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  Programme 388  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0013-936X ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8023  
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Author 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 ?g 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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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0048-9697 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8026  
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Author doi  openurl
  Title Strong migratory connectivity across meta-populations of sympatric North Atlantic seabirds Type Journal
  Year 2021 Publication Marine Ecology Progress Series Abbreviated Journal  
  Volume SEA Issue Pages  
  Keywords Environmental niche Inter-population mixing Large-scale spatiotemporal dynamics Light-level geolocation Murres Population spread Seasonality  
  Abstract  
  Programme 388  
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  Series Volume Series Issue Edition  
  ISSN 0171-8630, 1616-1599 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8027  
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Author doi  openurl
  Title Snow hardness impacts intranivean locomotion of arctic small mammals Type Journal
  Year 2021 Publication Ecosphere Abbreviated Journal  
  Volume 12 Issue 11 Pages e03835  
  Keywords Arctic burrowing behavior digging fossorial hardness lemming locomotion rain-on-snow rodent snow subnivean tunnel  
  Abstract Fossorial locomotion is often considered as the most energetically costly of all terrestrial locomotion. Small arctic rodents, such as lemmings, dig tunnels not only in the soil but also through the snowpack, which is present for over 8 months of the year. Lemmings typically dig in the softest snow layer called the depth hoar but with climate change, melt-freeze and rain-on-snow (ROS) events are expected to increase in the Arctic, leading to a higher frequency of hardened snowpacks. We assessed the impacts of snow hardness on the locomotion of two lemming species showing different morphological adaptations for digging. We hypothesized that an increase in snow hardness would (1) decrease lemming performance and (2) increase their effort while digging, but those responses would differ between lemming species. We exposed four brown lemmings (Lemmus trimucronatus) and three collared lemmings (Dicrostonyx groenlandicus) to snow of different hardness (soft, hard, and ROS) during 30-min trials (n = 63 trials) in a cold room and filmed their behavior. We found that the digging speed and tunnel length of both species decreased with snow hardness and density, underlining the critical role of snow properties in affecting lemming digging performance. During the ROS trials, time spent digging by lemmings increased considerably and they also started using their incisors to help break the hard snow, validating our second hypothesis. Overall, digging performance was higher in collared lemmings, the species showing more morphological adaptations to digging, than in brown lemmings. We conclude that the digging performance of lemming is highly dependent on snowpack hardness and that the anticipated increase in ROS events may pose a critical energetic challenge for arctic rodent populations.  
  Programme 1042  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2150-8925 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8028  
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Author Andreas Richter, Alexey A. Ekaykin, Matthias O. Willen, Vladimir Ya. Lipenkov, Andreas Groh, Sergey V. Popov, Mirko Scheinert, Martin Horwath, Reinhard Dietrich doi  openurl
  Title Surface Mass Balance Models Vs. Stake Observations: A Comparison in the Lake Vostok Region, Central East Antarctica Type Journal
  Year 2021 Publication Frontiers in Earth Science Abbreviated Journal  
  Volume 9 Issue Pages 388  
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  Programme 411  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2296-6463 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8030  
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Author Anzhou Cao, Zheng Guo, Xiaoyu Qi, Peiliang Li, Hailun He doi  openurl
  Title Seasonal and nodal variations of predominant tidal constituents in the global ocean Type Journal
  Year 2021 Publication Continental Shelf Research Abbreviated Journal  
  Volume 217 Issue Pages 104372  
  Keywords Fitting Modified two-step harmonic analysis Nodal modulation Seasonal variation Tide gauge Tides  
  Abstract Tides are one of the basic types of ocean water motions. Previous studies have reported that the M2 constituent exhibits seasonal variations (annual cycles) in some regions. However, based on the newly proposed method of modified two-step harmonic analysis (HA) and its application at 240 global tide gauges, we find that the M2 constituent as well as the S2 and K1 do not have significant seasonal variations at these tide gauges. The seasonal variations of the M2 constituent reported in previous studies are caused by its satellites, the H1 and H2 constituents, which are not resolved in these studies due to the short time window (one month or three months) used in HA. Because the frequency of the H1 (H2) constituent is equal to that of the M2 minus (plus) the frequency of annual cycles, the superposition of the M2, H1 and H2 constituents with constant amplitudes is equivalent to the M2 constituent with seasonally varying amplitudes. Compared with the new method, some adaptations to traditional HA aiming to capture variations in amplitudes and phase lags of constituents have some limitations, because they either neglect some satellites of the major constitutes or introduce spurious fluctuations resulting from an unreasonably large number of independent points. The nodal modulations of predominant constituents are also explored in this study. On the global scale, the nodal modulations of the M2, K1 and O1 constituents agree with the theoretical predictions, except a cold spot region with reduced nodal modulation in the Gulf of Maine and a hot spot region with enhanced nodal modulation in the South China Sea for the M2. Nodal modulation is also found for the S2 constituent (in theory, the S2 has no nodal modulation), which is 0.8% averaged at 164 tide gauges where the S2 is not too weak.  
  Programme 688  
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  Series Volume Series Issue Edition  
  ISSN 0278-4343 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8032  
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Author Mccoy, Kd doi  openurl
  Title Tick and tick-borne disease circulation in a changing marine ecosystem Type Book
  Year 2021 Publication In “Climate, Ticks and Disease” ed. Pat Nuttall, University of Oxford, UK, CABI Climate Change Series Abbreviated Journal  
  Volume Issue Pages  
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  Abstract This Book Brings Together Expert Opinions From Scientists To Consider The Evidence For Climate Change And Its Impacts On Ticks And Tick-borne Infections, And Provide Predictions For The Future. It Considers What Is Meant By 'Climate Change', How Good Are Climate Models Relevant To Ecosystems, And Predictions For Changes In Climate At Global, Regional, And Local Scales Relevant For Ticks And Tick-borne Infections. It Examines Changes To Tick Distribution And The Evidence That Climate Change Is Responsible. The Effect Of Climate On The Physiology And Metabolism Of Ticks, Including Potentially Critical Impacts On The Tick Microbiome Is Stressed. Given That The Notoriety Of Ticks Derives From Pathogens They Transmit, Do Changes In Climate Affect Vector Capacity? Ticks Transmit A Remarkable Range Of Micro- And Macro-parasites Many Of Which Are Pathogens Of Humans And Domesticated Animals. The Intimacy Between Tick-borne Agent And Tick Vector Means That Any Impacts Of Climate On A Tick Vector Will Impact Tick-borne Pathogens. Most Obviously, Such Impacts Will Be Apparent As Changes In Disease Incidence And Prevalence. The Evidence That Climate Change Is Affecting Diseases Caused By Tick-borne Pathogens Is Considered, Along With The Potential To Make Robust Predictions Of Future Events.  
  Programme 333  
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  Series Volume Series Issue Edition  
  ISSN 9781789249637 ISBN (up) Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8036  
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Author doi  openurl
  Title Landfast ice: a major driver of reproductive success in a polar seabird Type Journal
  Year 2021 Publication Biology Letters Abbreviated Journal  
  Volume 17 Issue 6 Pages 20210097  
  Keywords breeding success climate window analysis emperor penguin nonlinear effect sea ice  
  Abstract In a fast-changing world, polar ecosystems are threatened by climate variability. Understanding the roles of fine-scale processes, and linear and nonlinear effects of climate factors on the demography of polar species is crucial for anticipating the future state of these fragile ecosystems. While the effects of sea ice on polar marine top predators are increasingly being studied, little is known about the impacts of landfast ice (LFI) on this species community. Based on a unique 39-year time series of satellite imagery and in situ meteorological conditions and on the world's longest dataset of emperor penguin (Aptenodytes forsteri) breeding parameters, we?studied the effects of fine-scale variability of LFI and weather conditions on?this?species' reproductive success. We found that longer distances to the LFI edge (i.e. foraging areas) negatively affected the overall breeding success but also the fledging success. Climate window analyses suggested that chick mortality was particularly sensitive to LFI variability between August and November. Snowfall in May also affected hatching success. Given the sensitivity of LFI to storms and changes in wind direction, important future repercussions on the breeding habitat of emperor penguins are to be expected in the context of climate change.  
  Programme 109  
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  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8040  
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