| Records |
| Author |
Denis Mercier, Armelle Decaulne, Emilie Portier, Etienne Cossart |
| Title |
La datation des glissements de terrain paraglaciaires en Islande |
Type |
Poster |
Year  |
2022 |
Publication |
7th conference Climat & impacts, 23-25 novembre 2022, Gif-sur-Yvette, France (hal-03867107) |
Abbreviated Journal |
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| Volume |
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Issue |
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Pages |
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| Keywords |
Holocene Climatic Changes Landslides Paraglacial adjustment Rock slope failures |
| Abstract |
La fonte des glaciers islandais à partir de 15ka a été suivi par des ajustements paraglaciaires dont les glissements de terrain représentent une des manifestations les plus emblématiques. Un travail d’inventaire de leur répartition spatiale permet de comptabiliser plusieurs centaines de glissements, dont 158 dans la région du Skagafjörður au Nord de l’île, 186 dans les Westfjords et 290 dans les fjords de l’est. Les logiques spatiales de leur répartition permettent de montrer un contrôle lithologique à l’échelle globale avec une surreprésentation des glissements dans les basaltes d’âge tertiaire dans des régions où les contrastes topographiques sont par ailleurs majeurs à l’échelle de l’île. Au-delà de ces éléments spatiaux, la question de l’âge de leur mise en place se pose. Si l’on compare la chronologie de la déglaciation de l’Islande avec la répartition spatiale des glissements, nous observons une décroissance de l’occurrence potentielle des glissements de terrain avec le temps. La majorité des glissements se localisent le long des versants qui ont été libérés au tout début de la déglaciation. A l’échelle des glissements eux-mêmes, des études ponctuelles permettent de préciser l’âge de leur mise en place. Différentes approches sont alors mobilisées. La première prédate les glissements en utilisant l’emboîtement des formes géomorphologiques et l’âge des plages soulevées par le rebond glacio-isostatiques sur lesquelles viennent mourir les dépôts des glissements de terrain. La seconde série de mesures postdate les glissements. En effet, des dépressions au sein des glissements ont piégé des cendres volcaniques datées et des végétaux piégés dans des tourbières. Ainsi, par téphrochronologie et datation radiocarbone, il est possible d’obtenir des dates pour caler les événements gravitaires. Les modèles âge-profondeur sont également utilisés pour affiner les résultats. Ainsi, les glissements de terrain islandais, datés avec plus ou moins de précisions, donnent des âges postglaciaires compatibles avec le schéma d’une mise en place paraglaciaire dans les tous premiers temps de l’Holocène. |
| Programme |
1266 |
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Approved |
yes |
| Call Number |
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Serial |
8468 |
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| Author |
Antoine Rocaboy |
| Title |
Soil microbial biomass and nutrient concentrations under the effect of vegetation cover, biological invasion and habitats of the Kerguelen Islands. |
Type |
Master 1 |
| Year |
2022 |
Publication |
Rapport de stage de master 1, université de rennes 1 (encadrement: D. Renault, P. Agnola, N. Lebris) |
Abbreviated Journal |
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| Programme |
136 |
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Approved |
yes |
| Call Number |
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Serial |
8469 |
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| Author |
O. I. Berngardt, J.-P. St- Maurice, J. M. Ruohoniemi, A. Marchaudon |
| Title |
Seasonal and Diurnal Dynamics of Radio Noise for 8–20 MHz Poleward-Oriented Mid-Latitude Radars |
Type |
Journal |
| Year |
2022 |
Publication |
Radio Science |
Abbreviated Journal |
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| Volume |
57 |
Issue |
9 |
Pages |
e2021RS007338 |
| Keywords |
HF radars ionospheric absorption noise quiet-day curve radiowave propagation |
| Abstract |
Based on ray tracing in a smooth ionosphere described by the IRI-2012 model we have inferred the seasonal-diurnal dynamics of radio noise observed by four mid-latitude high-frequency (HF) radars. In the calculations, noise is assumed to be homogeneous and stationary, but the main contribution comes from the radar skip zone boundary due to focusing radiowaves effect. Noise absorption along the ray path is simulated from the IRI-2012 electron density, and from the molecular nitrogen density and electron temperatures obtained from the NRLMSISE-00 model. Earth magnetic field is not taken into account both in the absorption and ray-tracing calculations due to insufficient accuracy of the ionospheric model. The model results are compared with experimental radar data, and good agreement between the two is demonstrated. It is shown that experimentally observed seasonal and diurnal dynamics of the noise correlates well with model predictions. We demonstrated saturation effect at low noise levels. The model makes it possible to estimate the amount of absorption in D- and E-layers using noise observations at SuperDARN and SuperDARN-like poleward-oriented radars, especially at mid-latitudes. This is important for the retrieval of long term variations in the electron density in the lower ionosphere, by using wide coverage provided by these radars' network. The model also makes it feasible to interpret vertical absorption by experimental noise observations, thereby significantly expanding the capability of HF radars to monitor the lower ionosphere, and to provide data for joint analysis with other data, obtained by these radars at E- and F-layer heights. |
| Programme |
312 |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
1944-799X |
ISBN |
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Expedition |
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| Notes |
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Approved |
yes |
| Call Number |
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Serial |
8075 |
| Permanent link to this record |
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| Author |
Baptiste Le Bourg, Thomas Saucède, Anouk Charpentier, Gilles Lepoint, Loïc N. Michel |
| Title |
What is the menu today in a subantarctic kelp food web from the Kerguelen Islands? Phytodetritus, phytoplankton and phytobenthos; not living kelp |
Type |
Journal |
| Year |
2022 |
Publication |
Marine Biology |
Abbreviated Journal |
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| Volume |
169 |
Issue |
9 |
Pages |
118 |
| Keywords |
Benthic communities Food web Kelp forests Mixing models Stable isotopes |
| Abstract |
Kelp forests dominated by Macrocystis pyrifera are widely distributed in coastal waters from boreal, temperate and subantarctic regions. This widespread distribution may result in regional differences in food web structure and functioning. In temperate northern regions, where most studies on kelp forest benthic food webs have been conducted, kelp grazing is a well-documented phenomenon and can lead to the overgrazing of M. pyrifera by sea urchins when their predators (e.g., sea otters) are absent. In contrast, little is known about their counterparts in subantarctic areas. The present study aimed to reconstruct the benthic food web of a kelp forest dominated by M. pyrifera in a subantarctic environment using stable isotope analysis. Stable carbon (δ13C), nitrogen (δ15N) and sulfur (δ34S) isotope ratios were measured from food sources (macrophytobenthos, suspended particulate organic matter SPOM, and sediment) and consumers (sponges, bivalves, gastropods, sedentary and mobile polychaetes, arthropods and echinoderms) which were sampled in a kelp forest of the Kerguelen archipelago. Mixing models highlighted two interconnected trophic pathways which were either supported by SPOM and resuspended macrophytobenthos detritus (bentho-pelagic), or by live micro/macrophytobenthos (phytobenthos-based). No major prey were highlighted for several consumers, indicating the existence of potential supplementary trophic pathways. No consumer relying primarily on living M. pyrifera was highlighted by the mixing models. The investigated kelp forest is hence a complex ecosystem supporting multiple trophic pathways, and direct consumption of M. pyrifera is limited. Nonetheless, M. pyrifera and other macrophytobenthos species may constitute a pool of detritus supporting several trophic pathways. |
| Programme |
1044 |
| Campaign |
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Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1432-1793 |
ISBN |
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Expedition |
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Conference |
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| Notes |
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Approved |
yes |
| Call Number |
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Serial |
8474 |
| Permanent link to this record |
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| Author |
Samara Danel, Nancy Rebout, Francesco Bonadonna, Dora Biro |
| Title |
Wild skuas can use acoustic cues to locate hidden food |
Type |
Journal |
| Year |
2022 |
Publication |
Animal Cognition |
Abbreviated Journal |
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| Volume |
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Issue |
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Pages |
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| Keywords |
Acoustic cue Cups task Exclusion performance Inferential reasoning by exclusion Shaking |
| Abstract |
Among animals, the visual acuity of several predatory bird species is probably the most outstanding. This, and the ease with which visually based tasks are administered, has led researchers to predominantly use the visual modality when studying avian cognition. Some wild skua populations routinely use acoustic cues emitted by their prey during foraging. In this study, we thus assessed whether this species was able to locate hidden food using acoustic cues alone (training phase). During the subsequent test phase, we investigated the capacity of successful individuals to choose the correct baited container in four conditions: (i) baited (shaking the baited container), (ii) full information (shaking both containers), (iii) exclusion (shaking the empty container), and (iv) control (shaking neither container). Four out of ten subjects succeeded in locating the baited container in the training phase. During the test phase, most subjects chose the baited container significantly more than the empty container in the baited and full information condition, while their performance was at chance level in the control condition. When no sound emanated from the empty container in the exclusion condition, one out of four skuas chose the baited container with more accuracy than predicted by chance. As this bird chose correctly on the first trial and during the first five trials, its performance is unlikely due to learning processes (learning to exclude the empty container). Although further tests are necessary to draw firm conclusions, our results open the way for assessing further this species’ reasoning abilities in the wild. |
| Programme |
354 |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
1435-9456 |
ISBN |
1435-9456 |
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Expedition |
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| Notes |
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Approved |
yes |
| Call Number |
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Serial |
8297 |
| Permanent link to this record |
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| Author |
Thomas G Wilson, Elisa Goffo, Yann Alibert, Davide Gandolfi, Andrea Bonfanti, Carina M Persson, Andrew Collier Cameron, Malcolm Fridlund, Luca Fossati, Judith Korth, Willy Benz, Adrien Deline, Hans-Gustav Florén, Pascal Guterman, Vardan Adibekyan, Matthew J Hooton, Sergio Hoyer, Adrien Leleu, Alexander James Mustill, Sébastien Salmon, Sérgio G Sousa, Olga Suarez, Lyu Abe, Abdelkrim Agabi, Roi Alonso, Guillem Anglada, Joel Asquier, Tamas Bárczy, David Barrado Navascues, Susana C C Barros, Wolfgang Baumjohann, Mathias Beck, Thomas Beck, Nicolas Billot, Xavier Bonfils, Alexis Brandeker, Christopher Broeg, Edward M Bryant, Matthew R Burleigh, Marco Buttu, Juan Cabrera, Sébastien Charnoz, David R Ciardi, Ryan Cloutier, William D Cochran, Karen A Collins, Knicole D Colón, Nicolas Crouzet, Szilard Csizmadia, Melvyn B Davies, Magali Deleuil, Laetitia Delrez, Olivier Demangeon, Brice-Olivier Demory, Diana Dragomir, Georgina Dransfield, David Ehrenreich, Anders Erikson, Andrea Fortier, Tianjun Gan, Samuel Gill, Michaël Gillon, Crystal L Gnilka, Nolan Grieves, Sascha Grziwa, Manuel Güdel, Tristan Guillot, Jonas Haldemann, Kevin Heng, Keith Horne, Steve B Howell, Kate G Isaak, Jon M Jenkins, Eric L N Jensen, Laszlo Kiss, Gaia Lacedelli, Kristine Lam, Jacques Laskar, David W Latham, Alain Lecavelier des Etangs, Monika Lendl, Kathryn V Lester, Alan M Levine, John Livingston, Christophe Lovis, Rafael Luque, Demetrio Magrin, Wenceslas Marie-Sainte, Pierre F L Maxted, Andrew W Mayo, Brian McLean, Marko Mecina, Djamel Mékarnia, Valerio Nascimbeni, Louise D Nielsen, Göran Olofsson, Hugh P Osborn, Hannah L M Osborne, Roland Ottensamer, Isabella Pagano, Enric Pallé, Gisbert Peter, Giampaolo Piotto, Don Pollacco, Didier Queloz, Roberto Ragazzoni, Nicola Rando, Heike Rauer, Seth Redfield, Ignasi Ribas, George R Ricker, Martin Rieder, Nuno C Santos, Gaetano Scandariato, François-Xavier Schmider, Richard P Schwarz, Nicholas J Scott, Sara Seager, Damien Ségransan, Luisa Maria Serrano, Attila E Simon, Alexis M S Smith, Manfred Steller, Chris Stockdale, Gyula Szabó, Nicolas Thomas, Eric B Ting, Amaury H M J Triaud, Stéphane Udry, Vincent Van Eylen, Valérie Van Grootel, Roland K Vanderspek, Valentina Viotto, Nicholas Walton, Joshua N Winn |
| Title |
A pair of sub-Neptunes transiting the bright K-dwarf TOI-1064 characterized with CHEOPS |
Type |
Journal |
| Year |
2022 |
Publication |
Monthly Notices of the Royal Astronomical Society |
Abbreviated Journal |
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| Volume |
511 |
Issue |
1 |
Pages |
1043-1071 |
| Keywords |
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| Abstract |
We report the discovery and characterization of a pair of sub-Neptunes transiting the bright K-dwarf TOI-1064 (TIC 79748331), initially detected in the Transiting Exoplanet Survey Satellite (TESS) photometry. To characterize the system, we performed and retrieved the CHaracterising ExOPlanets Satellite (CHEOPS), TESS, and ground-based photometry, the High Accuracy Radial velocity Planet Searcher (HARPS) high-resolution spectroscopy, and Gemini speckle imaging. We characterize the host star and determine $T{\rm eff, \star }=4734\pm 67\,\mathrm{ K}$, $R{\star }=0.726\pm 0.007\, \mathrm{ R}{\odot }$, and $M{\star }=0.748\pm 0.032\, \mathrm{ M}{\odot }$. We present a novel detrending method based on point spread function shape-change modelling and demonstrate its suitability to correct flux variations in CHEOPS data. We confirm the planetary nature of both bodies and find that TOI-1064 b has an orbital period of Pb = 6.44387 ± 0.00003 d, a radius of Rb = 2.59 ± 0.04 R⊕, and a mass of $M{\rm b} = 13.5{-1.8}^{+1.7}$ M⊕, whilst TOI-1064 c has an orbital period of $P{\rm c} = 12.22657^{+0.00005}_{-0.00004}$ d, a radius of Rc = 2.65 ± 0.04 R⊕, and a 3σ upper mass limit of 8.5 M⊕. From the high-precision photometry we obtain radius uncertainties of ∼1.6 per cent, allowing us to conduct internal structure and atmospheric escape modelling. TOI-1064 b is one of the densest, well-characterized sub-Neptunes, with a tenuous atmosphere that can be explained by the loss of a primordial envelope following migration through the protoplanetary disc. It is likely that TOI-1064 c has an extended atmosphere due to the tentative low density, however further radial velocities are needed to confirm this scenario and the similar radii, different masses nature of this system. The high-precision data and modelling of TOI-1064 b are important for planets in this region of mass–radius space, and it allow us to identify a trend in bulk density–stellar metallicity for massive sub-Neptunes that may hint at the formation of this population of planets. |
| Programme |
1066 |
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| ISSN |
0035-8711 |
ISBN |
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| Notes |
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Approved |
yes |
| Call Number |
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Serial |
8303 |
| Permanent link to this record |
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| Author |
Estelle Cateau, Antoine Leclerc, Noémie Cartier, Isabel Valsecchi, Éric Bailly, Ronan Le Senechal, Margaux Becerra, Brice Le Gallou, Rose-Anne Lavergne, Adélaïde Chesnay, Jean-Patrice Robin, Carolyn Cray, Nicolas Goddard, Milan Thorel, Jacques Guillot, Baptiste Mulot, Guillaume Desoubeaux |
| Title |
Aspergillosis in a colony of Humboldt penguins (Spheniscus humboldti) under managed care: a clinical and environmental investigation in a French zoological park |
Type |
Journal |
| Year |
2022 |
Publication |
Medical Mycology |
Abbreviated Journal |
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| Volume |
60 |
Issue |
7 |
Pages |
myac046 |
| Keywords |
|
| Abstract |
Aspergillosis is pervasive in bird populations, especially those under human care. Its management can be critically impacted by exposure to high levels of conidia and by resistance to azole drugs. The fungal contamination in the environment of a Humboldt penguin (Spheniscus humboldti) group, housed in a French zoological park next to numerous large crop fields, was assessed through three serial sessions of surface sampling in nests, in 2018–20: all isolates were counted and characterized by sequencing. When identified as Aspergillus fumigatus, they were systematically screened for resistance mutations in the cyp51A gene and tested for minimal inhibitory concentrations (MICs) determination. At the same time, the clinical incidence of aspergillosis was evaluated in the penguin population by the means of systematic necropsy and mycological investigations. A microsatellite-based analysis tracked the circulation of A. fumigatus strains. Environmental investigations highlighted the substantial increase of the fungal load during the summer season (>12-fold vs. the other timepoints) and a large overrepresentation of species belonging to the Aspergillus section Fumigati, ranging from 22.7 to 94.6% relative prevalence. Only one cryptic species was detected (A. nishimurae), and one isolate exhibited G138S resistance mutation with elevated MICs. The overall incidence of aspergillosis was measured at ∼3.4% case-years, and mostly in juveniles. The analysis of microsatellite polymorphism revealed a high level of genetic diversity among A. fumigatus clinical isolates. In contrast, one environmental strain appeared largely overrepresented during the summer sampling session. In all, the rural location of the zoo did not influence the emergence of resistant strains.- The incidence of aspergillosis in the penguin population of a French zoo was found elevated, mostly in juveniles.- The fungal contamination was high in the surrounding environment, especially at the end of summer.- Globally, a great level of genetic diversity was observed, except for one clonal strain. |
| Programme |
119 |
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| ISSN |
1460-2709 |
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| Notes |
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Approved |
yes |
| Call Number |
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Serial |
8310 |
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| Author |
Florent Tencé, Julien Jumelet, Slimane Bekki, Sergey Khaykin, Alain Sarkissian, Philippe Keckhut |
| Title |
Australian Black Summer Smoke Observed by Lidar at the French Antarctic Station Dumont d’Urville |
Type |
Journal |
| Year |
2022 |
Publication |
Journal of Geophysical Research: Atmospheres |
Abbreviated Journal |
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| Volume |
127 |
Issue |
4 |
Pages |
e2021JD035349 |
| Keywords |
aerosol Antarctica lidar PSC pyrocumunolimbus stratosphere |
| Abstract |
In the follow-up of the Australian ”Black Summer” event that persisted from August 2019 to March 2020, we present the optical properties of the stratospheric aerosols injected into the atmosphere by these wildfires. The outbreak of pyrocumulonimbus (PyroCb) activity triggered between 2019/12/29 and 2020/01/04 has raised the stratospheric aerosol load of the Southern Hemisphere to unprecedented levels. Long-range transport brought some of the plumes down to the Antarctic region, where general circulation patterns kept them circling around the continent. The 532 nm Rayleigh/Mie/Raman ground-based lidar of the French Antarctic station Dumont d’Urville (66.6°S–140°E) acquired unprecedented time series of these carbonaceous aerosols starting approximately 20 days after the injection and up to the most recent measurements in October 2019 where local radiosonde reported anomalous ozone depletion as compared to the decadal average. The lidar provides a first and unique time series at high vertical and temporal resolution, complemented by satellite measurements from Ozone Monitoring Instrument, Ozone Mapping and Profiler Suite, and Microwave Limb Sounder. Aerosol backscatter ratio decreases from 1.9 to 1.2 between January and June 2020. Aerosol origin and persistence are characterized, as well as their optical properties and vertical distribution over several months. |
| Programme |
209 |
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| ISSN |
2169-8996 |
ISBN |
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Approved |
yes |
| Call Number |
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Serial |
8314 |
| Permanent link to this record |
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| Author |
Sam Christian, Andrew Vanderburg, Juliette Becker, Daniel A. Yahalomi, Logan Pearce, George Zhou, Karen A. Collins, Adam L. Kraus, Keivan G. Stassun, Zoe de Beurs, George R. Ricker, Roland K. Vanderspek, David W. Latham, Joshua N. Winn, S. Seager, Jon M. Jenkins, Lyu Abe, Karim Agabi, Pedro J. Amado, David Baker, Khalid Barkaoui, Zouhair Benkhaldoun, Paul Benni, John Berberian, Perry Berlind, Allyson Bieryla, Emma Esparza-Borges, Michael Bowen, Peyton Brown, Lars A. Buchhave, Christopher J. Burke, Marco Buttu, Charles Cadieux, Douglas A. Caldwell, David Charbonneau, Nikita Chazov, Sudhish Chimaladinne, Kevin I. Collins, Deven Combs, Dennis M. Conti, Nicolas Crouzet, Jerome P. de Leon, Shila Deljookorani, Brendan Diamond, René Doyon, Diana Dragomir, Georgina Dransfield, Zahra Essack, Phil Evans, Akihiko Fukui, Tianjun Gan, Gilbert A. Esquerdo, Michaël Gillon, Eric Girardin, Pere Guerra, Tristan Guillot, Eleanor Kate K. Habich, Andreea Henriksen, Nora Hoch, Keisuke I. Isogai, Emmanuël Jehin, Eric L. N. Jensen, Marshall C. Johnson, John H. Livingston, John F. Kielkopf, Kingsley Kim, Kiyoe Kawauchi, Vadim Krushinsky, Veronica Kunzle, Didier Laloum, Dominic Leger, Pablo Lewin, Franco Mallia, Bob Massey, Mayuko Mori, Kim K. McLeod, Djamel Mékarnia, Ismael Mireles, Nikolay Mishevskiy, Motohide Tamura, Felipe Murgas, Norio Narita, Ramon Naves, Peter Nelson, Hugh P. Osborn, Enric Palle, Hannu Parviainen, Peter Plavchan, Francisco J. Pozuelos, Markus Rabus, Howard M. Relles, Cristina Rodríguez López, Samuel N. Quinn, Francois-Xavier Schmider, Joshua E. Schlieder, Richard P. Schwarz, Avi Shporer, Laurie Sibbald, Gregor Srdoc, Caitlin Stibbards, Hannah Stickler, Olga Suarez, Chris Stockdale, Thiam-Guan Tan, Yuka Terada, Amaury Triaud, Rene Tronsgaard, William C. Waalkes, Gavin Wang, Noriharu Watanabe, Marie-Sainte Wenceslas, Geof Wingham, Justin Wittrock, Carl Ziegler |
| Title |
A Possible Alignment Between the Orbits of Planetary Systems and their Visual Binary Companions |
Type |
Journal |
| Year |
2022 |
Publication |
The Astronomical Journal |
Abbreviated Journal |
|
| Volume |
163 |
Issue |
5 |
Pages |
207 |
| Keywords |
|
| Abstract |
Astronomers do not have a complete picture of the effects of wide-binary companions (semimajor axes greater than 100 au) on the formation and evolution of exoplanets. We investigate these effects using new data from Gaia Early Data Release 3 and the Transiting Exoplanet Survey Satellite mission to characterize wide-binary systems with transiting exoplanets. We identify a sample of 67 systems of transiting exoplanet candidates (with well-determined, edge-on orbital inclinations) that reside in wide visual binary systems. We derive limits on orbital parameters for the wide-binary systems and measure the minimum difference in orbital inclination between the binary and planet orbits. We determine that there is statistically significant difference in the inclination distribution of wide-binary systems with transiting planets compared to a control sample, with the probability that the two distributions are the same being 0.0037. This implies that there is an overabundance of planets in binary systems whose orbits are aligned with those of the binary. The overabundance of aligned systems appears to primarily have semimajor axes less than 700 au. We investigate some effects that could cause the alignment and conclude that a torque caused by a misaligned binary companion on the protoplanetary disk is the most promising explanation. |
| Programme |
1066 |
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Original Title |
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Edition |
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| ISSN |
1538-3881 |
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| Notes |
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Approved |
yes |
| Call Number |
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Serial |
8317 |
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| Author |
Sabrina Tartu, Pierre Blévin, Paco Bustamante, Frédéric Angelier, Claus Bech, Jan Ove Bustnes, Melissa Chierici, Agneta Fransson, Geir W. Gabrielsen, Aurélie Goutte, Børge Moe, Christophe Sauser, Julien Sire, Christophe Barbraud, Olivier Chastel |
| Title |
A U-Turn for Mercury Concentrations over 20 Years: How Do Environmental Conditions Affect Exposure in Arctic Seabirds? |
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Journal |
| Year |
2022 |
Publication |
Environmental Science & Technology |
Abbreviated Journal |
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| Volume |
56 |
Issue |
4 |
Pages |
2443-2454 |
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| Abstract |
Mercury (Hg) is highly toxic in its methylated form (MeHg), and global change is likely to modify its bioavailability in the environment. However, it is unclear how top predators will be impacted. We studied blood Hg concentrations of chick-rearing black-legged kittiwakes Rissa tridactyla (2000–2019) in Svalbard (Norway). From 2000 to 2019, Hg concentrations followed a U-shaped trend. The trophic level, inferred from nitrogen stable isotopes, and chlorophyll a (Chl a) concentrations better predicted Hg concentrations, with positive and U-shaped associations, respectively. As strong indicators of primary productivity, Chl a concentrations can influence production of upper trophic levels and, thus, fish community assemblage. In the early 2000s, the high Hg concentrations were likely related to a higher proportion of Arctic prey in kittiwake’s diet. The gradual input of Atlantic prey in kittiwake diet could have resulted in a decrease in Hg concentrations until 2013. Then, a new shift in the prey community, added to the shrinking sea ice-associated release of MeHg in the ocean, could explain the increasing trend of Hg observed since 2014. The present monitoring provides critical insights about the exposure of a toxic contaminant in Arctic wildlife, and the reported increase since 2014 raises concern for Arctic seabirds. |
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330 |
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0013-936X |
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| Notes |
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Approved |
yes |
| Call Number |
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Serial |
8318 |
| Permanent link to this record |
