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	Author	P. Alken, E. Thébault, C. D. Beggan, J. Aubert, J. Baerenzung, W. J. Brown, S. Califf, A. Chulliat, G. A. Cox, C. C. Finlay, A. Fournier, N. Gillet, M. D. Hammer, M. Holschneider, G. Hulot, M. Korte, V. Lesur, P. W. Livermore, F. J. Lowes, S. Macmillan, M. Nair, N. Olsen, G. Ropp, M. Rother, N. R. Schnepf, C. Stolle, H. Toh, F. Vervelidou, P. Vigneron, I. Wardinski
	Title	Evaluation of candidate models for the 13th generation International Geomagnetic Reference Field			Type	Journal
	Year	2021	Publication	Earth, Planets and Space	Abbreviated Journal
	Volume	73	Issue	1	Pages	48
	Keywords	Geomagnetism IGRF Magnetic field modeling
	Abstract	In December 2019, the 13th revision of the International Geomagnetic Reference Field (IGRF) was released by the International Association of Geomagnetism and Aeronomy (IAGA) Division V Working Group V-MOD. This revision comprises two new spherical harmonic main field models for epochs 2015.0 (DGRF-2015) and 2020.0 (IGRF-2020) and a model of the predicted secular variation for the interval 2020.0 to 2025.0 (SV-2020-2025). The models were produced from candidates submitted by fifteen international teams. These teams were led by the British Geological Survey (UK), China Earthquake Administration (China), Universidad Complutense de Madrid (Spain), University of Colorado Boulder (USA), Technical University of Denmark (Denmark), GFZ German Research Centre for Geosciences (Germany), Institut de physique du globe de Paris (France), Institut des Sciences de la Terre (France), Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation (Russia), Kyoto University (Japan), University of Leeds (UK), Max Planck Institute for Solar System Research (Germany), NASA Goddard Space Flight Center (USA), University of Potsdam (Germany), and Université de Strasbourg (France). The candidate models were evaluated individually and compared to all other candidates as well to the mean, median and a robust Huber-weighted model of all candidates. These analyses were used to identify, for example, the variation between the Gauss coefficients or the geographical regions where the candidate models strongly differed. The majority of candidates were sufficiently close that the differences can be explained primarily by individual modeling methodologies and data selection strategies. None of the candidates were so different as to warrant their exclusion from the final IGRF-13. The IAGA V-MOD task force thus voted for two approaches: the median of the Gauss coefficients of the candidates for the DGRF-2015 and IGRF-2020 models and the robust Huber-weighted model for the predictive SV-2020-2025. In this paper, we document the evaluation of the candidate models and provide details of the approach used to derive the final IGRF-13 products. We also perform a retrospective analysis of the IGRF-12 SV candidates over their performance period (2015–2020). Our findings suggest that forecasting secular variation can benefit from combining physics-based core modeling with satellite observations.
	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	7937
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	Author	Pengcheng Wang, Natacha B. Bernier, Keith R. Thompson, Tsubasa Kodaira
	Title	Evaluation of a global total water level model in the presence of radiational S2 tide			Type	Journal
	Year	2021	Publication	Ocean Modelling	Abbreviated Journal
	Volume	168	Issue		Pages	101893
	Keywords	NEMO Radiational and gravitational tide Storm surge Tidal nudging Total water level
	Abstract	The development of a computationally efficient scheme for predicting the global distribution of total water level (TWL) is discussed. The ocean model is barotropic, has a horizontal grid spacing of 1/12°, and is based on the NEMO modeling framework. It is forced by the gravitational potential and hourly atmospheric fields for 2008. Hourly time spacing was required to resolve the S2 tide in global air pressure and wind. The predicted tide in water deeper than 400 m was nudged to TPXO8 “observations” of tidal elevation or current using a scheme called tidal nudging (Kodaira et al., 2019). The benefit of nudging horizontal velocity in the momentum equation, compared to sea level in the continuity equation, is discussed. Tidal nudging is shown to improve tidal predictions of sea level at the coast, particularly at the S2 tidal frequency. The predicted radiational S2 tide in sea level forced solely by the S2 tide in global air pressure reaches amplitudes exceeding 80 cm. Decreasing the time spacing of the air pressure forcing from 1 h to 3 h reduces the S2 amplitude in air pressure by a factor of 0.82, consistent with expectations based on Fourier analysis. This highlights the importance of using hourly atmospheric forcing when predicting the global sea level response to atmospheric forcing. The radiational S2 tide in sea level is subject to strong nonlinear interaction with the gravitational tide, leading to a pronounced attenuation of the radiational S2 tide. The attenuation is explained by an increase in effective bottom friction at the S2 frequency due to the presence of the gravitational tide. Four schemes for predicting TWL are evaluated to quantify the impact of tidal nudging and nonlinear interaction of tide and surge. Using TWLs observed by 304 coastal tide gauges, we show it is necessary to include both tidal nudging and nonlinear interaction. Plans for the further development of an operational flood forecast system for the Canadian coast, based on the above model, are discussed.
	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	1463-5003	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8356
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	Author	Jun Xie, Risheng Chu, Sidao Ni
	Title	Evaluating Global Tomography Models With Antipodal Ambient Noise Cross-Correlation Functions			Type	Journal
	Year	2021	Publication	Journal of Geophysical Research: Solid Earth	Abbreviated Journal
	Volume	126	Issue	3	Pages	e2020JB020444
	Keywords	ambient noise cross-correlation functions antipodal surface waves mantle heterogeneity tomography model evaluation
	Abstract	It is essential to evaluate global tomography models, which provide important information for understanding Earth's structure and dynamics. Long-period surface waves propagating between antipodal stations are good candidates for this purpose since they depend on global-scale velocity variations in the upper mantle. In this study, we extract minor-arc and major-arc Rayleigh waves from ambient noise cross correlations between GEOSCOPE station AIS and ∼1,800 USArray stations near the antipode of AIS. We identify two Rayleigh-wave-focusing regions and simulate the observed maximum amplitude pattern at the antipodal region using synthetic surface waves based on three global tomography models. Our simulations suggest that seismic heterogeneity of the tomography models need to be inflated by a factor of 2–3 in oceanic regions to explain the observed focusing pattern of surface waves near the antipodal region.
	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	2169-9356	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7993
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	Author	Alexis Burr
	Title	Etude de la fermeture des pores lors de la densification du névé polaire // Investigation of pore closure during polar firn densification			Type	Thesis
	Year	2021	Publication	Université de bretagne occidentale	Abbreviated Journal
	Volume	Thesis started in October 2021	Issue		Pages
	Keywords	540 Anisotropie Anisotropy Densification Discrete simulations Fermeture des pores Firn Névé Névés Pore closure Simulations discrètes Tomographie X Viscoplasticité X-Ray tomography
	Abstract	.La densification du névé en glace est un processus essentiel à comprendre pour interpréter les enregistrements climatiques. Une bonne connaissance des mécanismes permet une datation précise de l'air capturé dans la glace lors de la fermeture des pores. Celle-ci est plus vieille que l'air capturé à cause du transport des gaz dans la colonne de névé plus rapide que la densification de celui-ci. Cette différence d'âge entre la glace et le gaz est généralement appelé le Δage. La densification de la neige consiste en un processus complexe de réarrangement de grains, de frittage et de déformation viscoplastique. Bien que le comportement viscoplastique du cristal de glace soit fortement anisotrope, les modèles de densification actuels ne tiennent pas compte de cette anisotropie. De plus, le caractère granulaire du névé affecte aussi sa densification. La relation entre la fermeture des pores et les mécanismes microstructuraux sous-jacents est encore méconnue. Le but de cette thèse est d'incorporer l'aspect granulaire ainsi que l'anisotropie du cristal de glace dans une approche de modélisation innovante de la densification. Des expériences sur l'indentation viscoplastique de cylindres monocristallins de glace ont été réalisées pour proposer une loi de contact basée sur la théorie de l'indentation, et prenant en compte la déformation préférentielle du cristal de glace sur les plans basaux. Cette loi de contact a été implémentée dans un code utilisant la méthode des éléments discrets pour prédire la densification du névé.La micro-tomographie aux rayons X a été utilisée pour caractériser ex situ le névé polaire en trois dimensions à différentes étapes de la densification (ρ= 0.55-0.88 g/cm3), i.e. pour différentes profondeurs (~23 à 130m). Une étude fine de la fermeture des pores et de différentes caractéristiques morphologiques et physiques a été réalisée pour les sites polaires Dome C et Lock In. Des essais mécaniques ont aussi été réalisés in situ sur du névé extrait de Dome C dans le but de modéliser la densification du névé. Les observations microstructurales des expériences ex situ et in situ révèlent d'importantes différences dues aux vitesses relativement importantes utilisées lors des essais mécaniques. Ces vitesses rapides permettent de découpler la contribution des cinétiques de diffusion de la contribution viscoplastique de la déformation. Les effets de ces contributions sur la morphologie des pores et leurs fermetures sont discutés. Pour caractériser la fermeture des pores, cette thèse propose un indice de connectivité définit par le ratio entre le volume du plus gros pore sur la porosité totale. En effet, cet indice est plus approprié lors de l'utilisation de la tomographie aux rayons X que le ratio de pores fermés pour prédire la densité au close-off.
	Programme	1216
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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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8347
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	Author	Christian Zdanowicz, Jean-Charles Gallet, Mats P. Björkman, Catherine Larose, Thomas Schuler, Bartłomiej Luks, Krystyna Koziol, Andrea Spolaor, Elena Barbaro, Tõnu Martma, Ward van Pelt, Ulla Wideqvist, Johan Ström
	Title	Elemental and water-insoluble organic carbon in Svalbard snow: a synthesis of observations during 2007–2018			Type	Journal
	Year	2021	Publication	Atmospheric Chemistry and Physics	Abbreviated Journal
	Volume	21	Issue	4	Pages	3035-3057
	Keywords
	Abstract	Light-absorbing carbonaceous aerosols emitted by biomass or fossil fuel combustion can contribute to amplifying Arctic climate warming by lowering the albedo of snow. The Svalbard archipelago, being near to Europe and Russia, is particularly affected by these pollutants, and improved knowledge of their distribution in snow is needed to assess their impact. Here we present and synthesize new data obtained on Svalbard between 2007 and 2018, comprising measurements of elemental (EC) and water-insoluble organic carbon (WIOC) in snow from 37 separate sites. We used these data, combined with meteorological data and snowpack modeling, to investigate the variability of EC and WIOC deposition in Svalbard snow across latitude, longitude, elevation and time. Overall, EC concentrations (CsnowEC) ranged from <1.0 to 266.6 ng g−1, while WIOC concentrations (CsnowWIOC) ranged from <1 to 9426 ng g−1, with the highest values observed near Ny-Ålesund. Calculated snowpack loadings (LsnowEC, LsnowWIOC) on glaciers surveyed in spring 2016 were 0.1 to 2.6 mg m−2 and 2 to 173 mg m−2, respectively. The median CsnowEC and the LsnowEC on those glaciers were close to or lower than those found in earlier (2007–2009), comparable surveys. Both LsnowEC and LsnowWIOC increased with elevation and snow accumulation, with dry deposition likely playing a minor role. Estimated area-averaged snowpack loads across Svalbard were 1.1 mg EC m−2 and 38.3 mg WIOC m−2 for the 2015–2016 winter. An ∼11-year long dataset of spring surface snow measurements from the central Brøgger Peninsula was used to quantify the interannual variability of EC and WIOC deposition in snow. In most years, CsnowEC and CsnowWIOC at Ny-Ålesund (50 m a.s.l.) were 2–5 times higher than on the nearby Austre Brøggerbreen glacier (456 m a.s.l.), and the median EC/WIOC in Ny-Ålesund was 6 times higher, suggesting a possible influence of local EC emission from Ny-Ålesund. While no long-term trends between 2011 and 2018 were found, CsnowEC and CsnowWIOC showed synchronous variations at Ny-Ålesund and Austre Brøggerbreen. When compared with data from other circum-Arctic sites obtained by comparable methods, the median CsnowEC on Svalbard falls between that found in central Greenland (lowest) and those in continental sectors of European Arctic (northern Scandinavia, Russia and Siberia; highest), which is consistent with large-scale patterns of BC in snow reported by surveys based on other methods.
	Programme	1192
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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	1680-7316	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8604
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	Author	TaeOh Kwon, Hideaki Shibata, Sebastian Kepfer-Rojas, Inger K. Schmidt, Klaus S. Larsen, Claus Beier, Björn Berg, Kris Verheyen, Jean-Francois Lamarque, Frank Hagedorn, Nico Eisenhauer, Ika Djukic, TeaComposition Network , TaeOh Kwon, Hideaki Shibata, Sebastian Kepfer-Rojas, Inger Kappel Schmidt, Klaus Steenberg Larsen, Claus Beier, Björn Berg, Kris Verheyen, Jean Francois Lamarque, Frank Hagedorn, Nico Eisenhauer, Ika Djukic, Adriano Caliman, Alain Paquette, Alba Gutiérrez-Girón, Alessandro Petraglia, Algirdas Augustaitis, Amélie Saillard, Ana Carolina Ruiz-Fernández, Ana I. Sousa, Ana I. Lillebø, Anderson da Rocha Gripp, Andrea Lamprecht, Andreas Bohner, André-Jean Francez, Andrey Malyshev, Andrijana Andrić, Angela Stanisci, Anita Zolles, Anna Avila, Anna-Maria Virkkala, Anne Probst, Annie Ouin, Anzar A. Khuroo, Arne Verstraeten, Artur Stefanski, Aurora Gaxiola, Bart Muys, Beatriz Gozalo, Bernd Ahrends, Bo Yang, Brigitta Erschbamer, Carmen Eugenia Rodríguez Ortíz, Casper T. Christiansen, Céline Meredieu, Cendrine Mony, Charles Nock, Chiao-Ping Wang, Christel Baum, Christian Rixen, Christine Delire, Christophe Piscart, Christopher Andrews, Corinna Rebmann, Cristina Branquinho, Dick Jan, Dirk Wundram, Dušanka Vujanović, E. Carol Adair, Eduardo Ordóñez-Regil, Edward R. Crawford, Elena F. Tropina, Elisabeth Hornung, Elli Groner, Eric Lucot, Esperança Gacia, Esther Lévesque, Evanilde Benedito, Evgeny A. Davydov, Fábio Padilha Bolzan, Fernando T. Maestre, Florence Maunoury-Danger, Florian Kitz, Florian Hofhansl, Flurin Sutter, Francisco de Almeida Lobo, Franco Leadro Souza, Franz Zehetner, Fulgence Kouamé Koffi, Georg Wohlfahrt, Giacomo Certini, Gisele Daiane Pinha, Grizelle González, Guylaine Canut, Harald Pauli, Héctor A. Bahamonde, Heike Feldhaar, Heinke Jäger, Helena Cristina Serrano, Hélène Verheyden, Helge Bruelheide, Henning Meesenburg, Hermann Jungkunst, Hervé Jactel, Hiroko Kurokawa, Ian Yesilonis, Inara Melece, Inge van Halder, Inmaculada García Quirós, István Fekete, Ivika Ostonen, Jana Borovská, Javier Roales, Jawad Hasan Shoqeir, Jean-Christophe Lata, Jean-Luc Probst, Jeyanny Vijayanathan, Jiri Dolezal, Joan-Albert Sanchez-Cabeza, Joël Merlet, John Loehr, Jonathan von Oppen, Jörg Löffler, José Luis Benito Alonso, José-Gilberto Cardoso-Mohedano, Josep Peñuelas, Joseph C. Morina, Juan Darío Quinde, Juan J. Jiménez, Juha M. Alatalo, Julia Seeber, Julia Kemppinen, Jutta Stadler, Kaie Kriiska, Karel Van den Meersche, Karibu Fukuzawa, Katalin Szlavecz, Katalin Juhos, Katarína Gerhátová, Kate Lajtha, Katie Jennings, Katja Tielbörger, Kazuhiko Hoshizaki, Ken Green, Klaus Steinbauer, Laryssa Pazianoto, Laura Dienstbach, Laura Yahdjian, Laura J. Williams, Laurel Brigham, Lee Hanna, Liesbeth van den Brink, Lindsey Rustad, Lourdes Morillas, Luciana Silva Carneiro, Luciano Di Martino, Luis Villar, Luísa Alícida Fernandes Tavares, Madison Morley, Manuela Winkler, Marc Lebouvier, Marcello Tomaselli, Marcus Schaub, Maria Glushkova, Maria Guadalupe Almazan Torres, Marie-Anne de Graaff, Marie-Noëlle Pons, Marijn Bauters, Marina Mazón, Mark Frenzel, Markus Wagner, Markus Didion, Maroof Hamid, Marta Lopes, Martha Apple, Martin Weih, Matej Mojses, Matteo Gualmini, Matthew Vadeboncoeur, Michael Bierbaumer, Michael Danger, Michael Scherer-Lorenzen, Michal Růžek, Michel Isabellon, Michele Di Musciano, Michele Carbognani, Miglena Zhiyanski, Mihai Puşcaş, Milan Barna, Mioko Ataka, Miska Luoto, Mohammed H. Alsafaran, Nadia Barsoum, Naoko Tokuchi, Nathalie Korboulewsky, Nicolas Lecomte, Nina Filippova, Norbert Hölzel, Olga Ferlian, Oscar Romero, Osvaldo Pinto-Jr, Pablo Peri, Pavel Dan Turtureanu, Peter Haase, Peter Macreadie, Peter B. Reich, Petr Petřík, Philippe Choler, Pierre Marmonier, Quentin Ponette, Rafael Dettogni Guariento, Rafaella Canessa, Ralf Kiese, Rebecca Hewitt, Robert Weigel, Róbert Kanka, Roberto Cazzolla Gatti, Rodrigo Lemes Martins, Romà Ogaya, Romain Georges, Rosario G. Gavilán, Sally Wittlinger, Sara Puijalon, Satoshi Suzuki, Schädler Martin, Schmidt Anja, Sébastien Gogo, Silvio Schueler, Simon Drollinger, Simone Mereu, Sonja Wipf, Stacey Trevathan-Tackett, Stefan Stoll, Stefan Löfgren, Stefan Trogisch, Steffen Seitz, Stephan Glatzel, Susanna Venn, Sylvie Dousset, Taiki Mori, Takanori Sato, Takuo Hishi, Tatsuro Nakaji, Theurillat Jean-Paul, Thierry Camboulive, Thomas Spiegelberger, Thomas Scholten, Thomas J. Mozdzer, Till Kleinebecker, Tomáš Rusňák, Tshililo Ramaswiela, Tsutom Hiura, Tsutomu Enoki, Tudor-Mihai Ursu, Umberto Morra di Cella, Ute Hamer, Valentin Klaus, Valter Di Cecco, Vanessa Rego, Veronika Fontana, Veronika Piscová, Vincent Bretagnolle, Vincent Maire, Vinicius Farjalla, Vittoz Pascal, Wenjun Zhou, Wentao Luo, William Parker, Yasuhiro Utsumi, Yuji Kominami, Zsolt Kotroczó, Zsolt Tóth
	Title	Effects of Climate and Atmospheric Nitrogen Deposition on Early to Mid-Term Stage Litter Decomposition Across Biomes			Type	Journal
	Year	2021	Publication	Frontiers in Forests and Global Change	Abbreviated Journal
	Volume	4	Issue		Pages
	Keywords
	Abstract	Litter decomposition is a key process for carbon and nutrient cycling in terrestrial ecosystems and is mainly controlled by environmental conditions, substrate quantity and quality as well as microbial community abundance and composition. In particular, the effects of climate and atmospheric nitrogen (N) deposition on litter decomposition and its temporal dynamics are of significant importance, since their effects might change over the course of the decomposition process. Within the TeaComposition initiative, we incubated Green and Rooibos teas at 524 sites across nine biomes. We assessed how macroclimate and atmospheric inorganic N deposition under current and predicted scenarios (RCP 2.6, RCP 8.5) might affect litter mass loss measured after 3 and 12 months. Our study shows that the early to mid-term mass loss at the global scale was affected predominantly by litter quality (explaining 73% and 62% of the total variance after 3 and 12 months, respectively) followed by climate and N deposition. The effects of climate were not litter-specific and became increasingly significant as decomposition progressed, with MAP explaining 2% and MAT 4% of the variation after 12 months of incubation. The effect of N deposition was litter-specific, and significant only for 12-month decomposition of Rooibos tea at the global scale. However, in the temperate biome where atmospheric N deposition rates are relatively high, the 12-month mass loss of Green and Rooibos teas decreased significantly with increasing N deposition, explaining 9.5% and 1.1% of the variance, respectively. The expected changes in macroclimate and N deposition at the global scale by the end of this century are estimated to increase the 12-month mass loss of easily decomposable litter by 1.1–3.5% and of the more stable substrates by 3.8–10.6%, relative to current mass loss. In contrast, expected changes in atmospheric N deposition will decrease the mid-term mass loss of high-quality litter by 1.4–2.2% and that of low-quality litter by 0.9–1.5% in the temperate biome. Our results suggest that projected increases in N deposition may have the capacity to dampen the climate-driven increases in litter decomposition depending on the biome and decomposition stage of substrate.
	Programme	136
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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	2624-893X	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8301
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	Author	Maria Federica Marcucci, Igino Coco, Stefano Massetti, Alessio Pignalberi, Victoriya Forsythe, Michael Pezzopane, Alexander Koustov, Simona Longo, David Biondi, Enrico Simeoli, Giuseppe Consolini, Monica Laurenza, Aurélie Marchaudon, Andrea Satta, Alessandro Cirioni, Angelo De Simone, Angelo Olivieri, Alessandro Baù, Alberto Salvati
	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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	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	1873-9652	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8020
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	Author	Pamela E. Michael, Chris Wilcox, Christophe Barbraud, Karine Delord, Michael Sumner, Henri Weimerskirch
	Title	Dynamic enforcement of bycatch via reproductive value can increase theoretical efficiency			Type	Journal
	Year	2021	Publication	Marine Policy	Abbreviated Journal
	Volume	132	Issue		Pages	104684
	Keywords	Albatross Bycatch Dynamic enforcement Dynamic ocean management Monitoring Reproductive value
	Abstract	Managing marine systems is challenging, as many marine species are highly mobile. Albatross exemplify this paradigm, overlapping multiple threats at sea, including bycatch. The typical characterization of bycatch, the number of individuals, ignores the long-term, population-wide repercussions of bycatch. Including an estimate of the reproductive value (RV, the loss of future reproductive contributions, given bycatch) is a complementary tool, incorporating the population-wide repercussions of bycatch. While bycatch management via dynamic spatial management allows management boundaries to move, it requires monitoring and enforcement to be effective. We provide a proof of concept to optimize bycatch enforcement activities by dynamically targeting areas of concentrated future productivity characterized by RV. This paper examined a population of black-browed albatross (Thalassarche melanophris) as a case study. We calculate RV and apply it to at-sea distributions. This creates spatiotemporally explicit surfaces used to prioritize times and locations for bycatch mitigation enforcement. Dynamic enforcement has greater theoretical efficiency than static enforcement, but this difference decreases with increasing population-wide RV subject to enforcement. Though there are implementation challenges, many can be reduced with existing tools providing various opportunities. Incorporating RV when characterizing the impacts of bycatch on a population and strategically applying dynamic bycatch enforcement based on RV can be a powerful, efficient component of dynamic ocean management.
	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	0308-597X	ISBN	0308-597X	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8342
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	Author	Najat Bhiry, Dominique Marguerie, Tommy Weetaluktuk, Myosotis Desroches Bourgon, David Aoustin, Pierre M. Desrosiers, Dominique Todisco
	Title	Dorset and Thule Inuit occupations of Qikirtajuaq (Smith Island), Nunavik, Canada: a palaeoecological approach			Type	Journal
	Year	2021	Publication		Abbreviated Journal
	Volume	Boreas	Issue		Pages	826-843
	Keywords
	Abstract	Qikirtajuaq is a long island facing the Inuit village of Akulivik on the northeastern coast of Hudson Bay (Canada) that is rich in archaeological sites. Kangiakallak-1 (JeGn-2), one of the main sites on this island, is a large multicomponent site that includes Dorset and Thule Inuit winter houses. This study documents the dynamics of palaeoenvironmental conditions in the successive occupations of the Kangiakallak-1 settlement based on plant macrofossils, pollen and non-pollen palynomorph analyses and archaeological research. The data indicate that Dorset inhabitants constructed their dwelling at about 772 cal. a BP. The site was reused by the Thule Inuit a few decades later, starting at about 671 cal. a BP. Thus, Kangiakallak-1 is one of the few sites, at least in Nunavik (northern Quebec, Canada), that were rapidly reoccupied by the Thule Inuit after the departure of the Dorset inhabitants, which indicates a possible overlap between the two cultures in the Akulivik region. The palaeoecological data show that both Dorset and Thule inhabitants left clear footprints at the local scale in the form of several nitrophilous species that became established in and near the houses and persisted over a long period. The deposition of domestic waste (including bone fragments, skin, burnt fat and charcoal fragments) inside the subterranean dwellings fertilized the soil and led to the growth of unique nitrophilous plants. These changes transformed the houses into exceptional floristic refuges.
	Programme	1080
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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	0300-9483	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8520
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	Author	Daniela Levicoy, Sebastián Rosenfeld, Leyla Cárdenas
	Title	Divergence time and species delimitation of microbivalves in the Southern Ocean: the case of Kidderia species			Type	Journal
	Year	2021	Publication	Polar Biology	Abbreviated Journal
	Volume	44	Issue	7	Pages	1365-1377
	Keywords
	Abstract	The systematics of Subantarctic and Antarctic near-shore marine benthic invertebrates requires major revision and highlights the necessity to incorporate additional sources of information in the specimen identification chart in the Southern Ocean (SO). In this study, we aim to improve our understanding of the biodiversity of Kidderia (Dall 1876) through molecular and morphological comparisons of Antarctic and Subantarctic taxa. The microbivalves of the genus Kidderia are small brooding organisms that inhabit intertidal and shallow subtidal rocky ecosystems. This genus represents an interesting model to test the vicariance and dispersal hypothesis in the biogeography of the SO. However, the description of Kidderia species relies on a few morphological characters and biogeographic records that raise questions about the true diversity in the group. Here we will define the specimens collected with genetic tools, delimiting their respective boundaries across provinces of the SO, validating the presence of two species of Kidderia. Through the revision of taxonomic issues and species delimitation, it was possible to report that the Antarctic species is Kidderia subquadrata and the species recorded in the Subantarctic islands Diego Ramirez, South Georgia and the Kerguelen Archipelago is Kidderia minuta. The divergence time estimation suggests the origin and diversification of Kidderia lineages are related to historical vicariant processes probably associated with the separation of the continental landmasses close to the late Eocene.
	Programme	1044
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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	1432-2056	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	8004
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