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	Author	Rémi Amiraux, Christopher Burot, Patricia Bonin, Guillaume Massé, Sophie Guasco, Marcel Babin, Frédéric Vaultier, Jean-François Rontani
	Title	Stress factors resulting from the Arctic vernal sea-ice melt: Impact on the viability of bacterial communities associated with sympagic algae			Type	Journal
	Year	2020	Publication	Elementa: Science of the Anthropocene	Abbreviated Journal
	Volume	8	Issue	1	Pages
	Keywords
	Abstract	During sea-ice melt in the Arctic, primary production by sympagic (sea-ice) algae can be exported efficiently to the seabed if sinking rates are rapid and activities of associated heterotrophic bacteria are limited. Salinity stress due to melting ice has been suggested to account for such low bacterial activity. We further tested this hypothesis by analyzing samples of sea ice and sinking particles collected from May 18 to June 29, 2016, in western Baffin Bay as part of the Green Edge project. We applied a method not previously used in polar regions—quantitative PCR coupled to the propidium monoazide DNA-binding method—to evaluate the viability of bacteria associated with sympagic and sinking algae. We also measured cis-trans isomerase activity, known to indicate rapid bacterial response to salinity stress in culture studies, as well as free fatty acids known to be produced by algae as bactericidal compounds. The viability of sympagic-associated bacteria was strong in May (only approximately 10% mortality of total bacteria) and weaker in June (average mortality of 43%; maximum of 75%), with instances of elevated mortality in sinking particle samples across the time series (up to 72%). Short-term stress reflected by cis-trans isomerase activity was observed only in samples of sinking particles collected early in the time series. Following snow melt, however, and saturating levels of photosynthetically active radiation in June, we observed enhanced ice-algal production of bactericidal compounds (free palmitoleic acid; up to 4.8 mg L–1). We thus suggest that protection of sinking sympagic material from bacterial degradation early in a melt season results from low bacterial activity due to salinity stress, while later in the season, algal production of bactericidal compounds induces bacterial mortality. A succession of bacterial stressors during Arctic ice melt helps to explain the efficient export of sea-ice algal material to the seabed.
	Programme	1164
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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	2325-1026	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8118
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	Author	Julie Sansoulet, Michèle Therrien, Joseph Delgove, Guilhem Pouxviel, Julie Desriac, Noé Sardet, Jean-Paul Vanderlinden
	Title	An update on Inuit perceptions of their changing environment, Qikiqtaaluk (Baffin Island, Nunavut)			Type	Journal
	Year	2020	Publication	Elementa: Science of the Anthropocene	Abbreviated Journal
	Volume	8	Issue	1	Pages
	Keywords
	Abstract	The Inuit of Qikiqtaaluk (Baffin Island) have developed a deep respect for their natural environment and are able to report not only changes in weather, ice, and natural resources but also changes in their communities as a result of climate change. The objective of this study was to shed light on how the impacts of climate change are currently perceived in the communities of Kanngiqtugaapik, Pangniqtuuq, and Qikiqtarjuaq. In order to construct a shared knowledge base, we conducted qualitative video interviews and participated in a hunting camp with multigenerational and multigender Inuit hunters and fishers. First, Inuit continue to see the world in which they cohabit with other living things, particularly animals, as a world that they cannot control on their own—a world they must adapt to, passing learning from one generation to the next. Second, they report that changes in the ice have been among the major and most important transformations to have occurred in recent decades. Observations made by these local populations also indicate changes in hunted species, with fewer caribou and narwhal, more birds, insects, and fish, including from more southerly regions, and an uncertainty about polar bear populations. Seal hunting remains stable, and this meat is still the most popular and healthy food, physically and psychologically. Third, sociological and economic changes (e.g., lifestyle change, monetary economies, quotas), in addition to environmental changes (e.g., climate change, species change), have had a significant impact on food harvesting activities as well as food consumption in the region. A final perspective concerns the needs of the Qikiqtaaluk communities to further develop collaboration with scientists. This need for partnership is not only perceived as a scientific necessity but also recognized by Inuit as essential to their communities, with some local leaders ready to work toward a fruitful collaboration.
	Programme	1164
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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	2325-1026	ISBN	2325-1026	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8117
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	Author	Tonya M. Burgers, Jean-Éric Tremblay, Brent G. T. Else, Tim N. Papakyriakou
	Title	Estimates of net community production from multiple approaches surrounding the spring ice-edge bloom in Baffin Bay			Type	Journal
	Year	2020	Publication	Elementa: Science of the Anthropocene	Abbreviated Journal
	Volume	8	Issue	1	Pages
	Keywords
	Abstract	Measurements of net community production (NCP) provide an upper constraint on the strength of the oceanic biological pump, the dominant mechanism for removing CO2 from the ocean surface and sequestering it at depth. In this investigation, our objectives were to describe the spatial and temporal variability of NCP associated with the spring ice-edge bloom in Baffin Bay and to identify the key environmental drivers controlling its variability. Using data collected between June 9 and July 10, 2016, we estimated NCP based on (1) underway measurements of surface water oxygen to argon ratios (O2:Ar), (2) underway measurements of the partial pressure of CO2, and (3) seasonal nitrate drawdown from discrete samples. These multiple approaches displayed high NCP (up to 5.7 mol C m–2) in eastern Baffin Bay, associated with modified Atlantic waters, and low NCP (<1 mol C m–2) in the presence of Arctic outflow waters in western Baffin Bay. Arctic outflow waters were characterized by low surface salinities and nitrate concentrations, suggesting that high freshwater content may have limited the nutrient availability of these waters. Different integration depths and timescales associated with each NCP approach were exploited to understand the temporal progression and succession of the bloom, revealing that the bloom was initiated under ice up to 15 days prior to ice retreat and that a large portion of NCP in eastern Baffin Bay (potentially up to 70%) was driven by primary production occurring below the surface-mixed layer.
	Programme	1164
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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	2325-1026	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8116
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	Author	David Boertmann, Flemming Merkel, Olivier Gilg
	Title	Seabird Breeding Colonies in East and North Greenland: A Baseline			Type	Journal
	Year	2020	Publication	ARCTIC	Abbreviated Journal
	Volume	73	Issue	1	Pages	20-39
	Keywords	climate change colonial seabirds distribution Greenland
	Abstract	This paper presents the results of a number of aircraft- and boat-based surveys for seabird breeding colonies in East and North Greenland carried out in the period 2003 to 2018 and gives the first comprehensive overview of the distribution and size of the seabird breeding colonies in this remote and mainly uninhabited region. Seventeen seabird species breed in approximately 800 sites distributed very unevenly along the coasts, with high concentrations at the polynyas and long stretches with very few breeding seabirds. Climate changes are in full progress in East and North Greenland, especially affecting the sea ice regime, and seabirds are expected to respond to these changes in different ways. For example, since the 1980s, Common Eiders (Somateria mollissima) have extended their breeding range more than two latitudinal degrees towards the north, now reaching the northernmost land on Earth. Lesser Black-backed Gulls (Larus fuscus) and Great Cormorants (Phalacrocorax carbo) have immigrated, and Sabine’s Gulls (Xema sabini) have increased and extended their range. Besides presenting survey results, this report may also serve as a baseline for future studies of the abundance of breeding seabirds in East and North Greenland.
	Programme	1036
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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	1923-1245	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7681
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	Author	Pauline Goulet, Christophe Guinet, Claudio Campagna, Julieta Campagna, Peter Lloyd Tyack, Mark Johnson
	Title	Flash and grab: deep-diving southern elephant seals trigger anti-predator flashes in bioluminescent prey			Type	Journal
	Year	2020	Publication	Journal of Experimental Biology	Abbreviated Journal
	Volume	223	Issue	10	Pages
	Keywords
	Abstract	Bioluminescence, which occurs in approximately 80% of the world's mesopelagic fauna, can take the form of a low-intensity continuous glow (e.g. for counter-illumination or signalling) or fast repetitions of brighter anti-predatory flashes. The southern elephant seal (SES) is a major consumer of mesopelagic organisms, in particular the abundant myctophid fish, yet the fine-scale relationship between this predator's foraging behaviour and bioluminescent prey remains poorly understood. We hypothesised that brief, intense light emissions should be closely connected with prey strikes when the seal is targeting bioluminescent prey that reacts by emitting anti-predator flashes. To test this, we developed a biologging device containing a fast-sampling light sensor together with location and movement sensors to measure simultaneously anti-predator bioluminescent emissions and the predator's attack motions with a 20 ms resolution. Tags were deployed on female SES breeding at Kerguelen Islands and Península Valdés, Argentina. In situ light levels in combination with duration of prey capture attempts indicated that seals were targeting a variety of prey types. For some individuals, bioluminescent flashes occurred in a large proportion of prey strikes, with the timing of flashes closely connected with the predator's attack motion, suggestive of anti-predator emissions. Marked differences across individuals and location indicate that SES do exploit bioluminescent organisms but the proportion of these in the diet varies widely with location. The combination of wideband light and acceleration data provides new insight into where and when different prey types are encountered and how effectively they might be captured.
	Programme	1201
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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	0022-0949	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8008
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	Author	I. Wardinski, D. Saturnino, H. Amit, A. Chambodut, B. Langlais, M. Mandea, E. Thébault
	Title	Geomagnetic core field models and secular variation forecasts for the 13th International Geomagnetic Reference Field (IGRF-13)			Type	Journal
	Year	2020	Publication	Earth, Planets and Space	Abbreviated Journal
	Volume	72	Issue	1	Pages	155
	Keywords	Forecasts of the geomagnetic field Geomagnetic field models Geomagnetic secular variation The geomagnetic field
	Abstract	Observations of the geomagnetic field taken at Earth’s surface and at satellite altitude are combined to construct continuous models of the geomagnetic field and its secular variation from 1957 to 2020. From these parent models, we derive candidate main field models for the epochs 2015 and 2020 to the 13th generation of the International Geomagnetic Reference Field (IGRF). The secular variation candidate model for the period 2020–2025 is derived from a forecast of the secular variation in 2022.5, which results from a multi-variate singular spectrum analysis of the secular variation from 1957 to 2020.
	Programme	139
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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	1880-5981	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7364
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	Author	J. Díaz, M. Ruiz, J. J. Curto, J. M. Torta, J. Ledo, A. Marcuello, P. Queralt
	Title	On the observation of magnetic events on broad-band seismometers			Type	Journal
	Year	2020	Publication	Earth, planets and space	Abbreviated Journal
	Volume	72	Issue	1	Pages	109
	Keywords	Anthropogenic sources of magnetic noise Seismic instrumentation Sudden Storm Commencements
	Abstract	The objective of this contribution is to get new insights into the effects of magnetic field variations of natural and anthropogenic origin on broad-band seismic stations. Regarding natural sources of magnetic perturbations, we have investigated if the Sudden Storm Commencements (SSC) cataloged during the 24th solar cycle (2008–2019) can be systematically identified in broad-band seismic stations distributed worldwide. The results show that the 23 SSC events with a mean amplitude above 30 nT and most of those with lower energy but still clearly identified in the magnetometer detection network can be observed at broad-band stations’ network using a simple low-pass filter. Although the preliminary impulse of those signals is usually stronger at stations located at high latitudes, major SSC are observed at seismic stations distributed worldwide. Regarding anthropogenic sources, we focus on the short period seismic signals recorded in urban environments which are correlated with the activity of the railway transportation system. We have analyzed collocated measurements of electric field and seismic signals within Barcelona, evidencing that significant changes in the electric field following the activity of the transportation systems can be attributed to leakage currents transmitted to the soil by trains. During space weather events, electric currents in the magnetosphere and ionosphere experience large variations inducing telluric currents near the Earth surface, which in turn generate a secondary magnetic field. In the case of underground trains, leakage currents are transmitted to the soil, which in turn can result in local variations in the magnetic field. The observed signals in modern seismometers can be related to the reaction of the suspension springs to these magnetic field variations or to the effect of the magnetic field variations on the force transducers used to keep the mass fixed.
	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	1880-5981	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7888
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	Author	Petra Quillfeldt, Henri Weimerskirch, Karine Delord, Yves Cherel
	Title	Niche switching and leapfrog foraging: movement ecology of sympatric petrels during the early breeding season			Type	Journal
	Year	2020	Publication	Movement Ecology	Abbreviated Journal
	Volume	8	Issue	1	Pages	23
	Keywords	Breeding schedule Central-place forager Foraging ecology Tracking
	Abstract	The timing of events in the early part of the breeding season is crucially important for successful reproduction. Long-lived animals that migrate large distances independently of each other meet at the breeding sites to re-establish their pair bonds and coordinate their breeding duties with their partners.
	Programme	109
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2051-3933	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8080
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	Author	Barbara Delmonte, Holly Winton, Mélanie Baroni, Giovanni Baccolo, Margareta Hansson, Per Andersson, Carlo Baroni, Maria Cristina Salvatore, Luca Lanci, Valter Maggi
	Title	Holocene dust in East Antarctica: Provenance and variability in time and space			Type	Journal
	Year	2020	Publication	The Holocene	Abbreviated Journal
	Volume	30	Issue	4	Pages	546-558
	Keywords	East Antarctica ice cores dust dust stratigraphy Holocene provenance
	Abstract	In this paper, we provide a comprehensive overview of the state-of-knowledge of dust flux and variability in time and space in different sectors of East Antarctica during the Holocene. By integrating the literature data with new evidences, we discuss the dust flux and grain-size variability during the current interglacial and its provenance in the innermost part of the East Antarctic plateau as well as in peripheral regions located close to the Transantarctic Mountains. The local importance of aeolian mineral dust aerosol deflated from low-elevation areas of peripheral East Antarctica is also discussed in the light of new data from several coastal, low-elevation sites.
	Programme	1145
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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	0959-6836	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7610
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	Author	M. Belke-Brea, F. Domine, S. Boudreau, G. Picard, M. Barrere, L. Arnaud, M. Paradis
	Title	New Allometric Equations for Arctic Shrubs and Their Application for Calculating the Albedo of Surfaces with Snow and Protruding Branches			Type	Journal
	Year	2020	Publication	Journal of Hydrometeorology	Abbreviated Journal
	Volume	21	Issue	11	Pages	2581-2594
	Keywords
	Abstract	Arctic shrubs reduce surface albedo in winter when branches protrude above the snow. To calculate the albedo of those mixed surfaces, the branch area index (BAI) of Arctic shrubs needs to be known. Moreover, an exposed-vegetation function is required to determine the BAI for protruding branches only. This study used a structural analysis of 30 Betula glandulosa shrubs, sampled near Umiujaq, northern Quebec, to (i) establish an allometric relationship between shrub height and BAI and (ii) determine a specific exposed-vegetation function for Arctic shrubs. The spectral albedo (400–1080 nm) of mixed surfaces was then simulated with the equations derived from this study and validated with in situ measured spectra. Shrubs were sampled from two sites, one along the coast and the other in a nearby valley. The shrub height–BAI relationship varied between both sites. BAI values of shrubs growing in the wind-sheltered valley were 30%–50% lower. The exposed-vegetation function obtained here differed from the linear functions found in the literature. The linear functions strongly overestimated the BAI of exposed branches. Albedo was well simulated with an accuracy of 3% when using an allometric relationship adapted to the environmental conditions of our study site. However, simulated albedo values were consistently higher than field measurements, probably because radiation absorbed by impurities and buried branches was neglected in the model. We conclude that specific exposed-vegetation and allometric equations need to be implemented in models to accurately simulate the albedo of mixed snow–shrub surfaces.
	Programme	1042
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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	1525-7541, 1525-755X	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7970
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