Caillon, N.; Jouzel, J.; Severinghaus, J.P.; Chappellaz, J.; Blunier, T. (2003). A novel method to study the phase relationship between Antarctic and Greenland climate. Geophysical research letters, 30.
Abstract: A classical method for understanding the coupling between northern and southern hemispheres during millennial-scale climate events is based on the correlation between Greenland and Antarctic ice core records of atmospheric composition. Here we present a new approach based on the use of a single Antarctic ice core in which measurements of methane concentration and inert gas isotopes place constraints on the timing of a rapid climate change in the North and of its Antarctic counterpart. We applied it to the Marine Isotope Stage (MIS) 5d/c transition early in the last glaciation ?108 ky BP. Our results indicate that the Antarctic temperature increase occurred 2 ky before the methane increase, which is used as a time marker of the warming in the Northern Hemisphere. This result is in agreement with the “bipolar seesaw” mechanism used to explain the phase relationships documented between 23 and 90 ky BP [
Blunier and Brook, 2001].
Keywords: 3344 Meteorology and Atmospheric Dynamics: Paleoclimatology; 4267 Oceanography: General: Paleoceanography; 1827 Hydrology: Glaciology; 4870 Oceanography: Biological and Chemical: Stable isotopes; 1620 Global Change: Climate dynamics
Programme: 902
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Florenchie P., Le Provost C., Blayo E. & Verron J. (1995). A numerical model of the South Atlantic Ocean with assimilation of Topex-Poseidon data: predictions of the ACC frontal structures. (Vol. 115).
Abstract: IOC Workshop Report on 'Sea Level variability and Southern Ocean Dynamics'
Programme: 688
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Parish T.R., Pettre P. & Wendler G. (1993). A numerical study of the diurnal variation of the Adelie Land katabatic wind regime. J. Geophys. Res., 98(d7), 12933–12947.
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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. (2022). A pair of sub-Neptunes transiting the bright K-dwarf TOI-1064 characterized with CHEOPS (Vol. 511).
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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Chuxian Li, Maxime Enrico, Oliver Magand, Beatriz F. Araujo, Gaël Le Roux, Stefan Osterwalder, Aurélien Dommergue, Yann Bertrand, Jérôme Brioude, François De Vleeschouwer, Jeroen E. Sonke. (2023). A peat core Hg stable isotope reconstruction of Holocene atmospheric Hg deposition at Amsterdam Island (37.8oS) (Vol. 341).
Abstract: Mercury (Hg) stable isotopes have been broadly used to investigate the sources, transformation and deposition of atmospheric Hg during the industrial era thanks to the multiple isotope signatures deriving from mass-dependent (represented by δ202Hg) and mass-independent fractionation (represented by ΔxxxHg) in the environment. Less is known about the impact of past climate change on atmospheric Hg deposition and cycling, and whether Hg isotopes covary with past climate. Here, we investigate Hg concentration and Hg isotope signatures in a 6600-year-old ombrotrophic peat record from Amsterdam Island (AMS, 37.8oS), and in modern AMS rainfall and gaseous elemental Hg (Hg0) samples. Results show that Holocene atmospheric Hg deposition and plant Hg uptake covary with dust deposition, and are both lower under a high humidity regime associated with enhanced Southern Westerly Winds. Modern AMS gaseous Hg0 and rainfall HgII isotope signatures are similar to those in the Northern Hemisphere (NH). Holocene peat Δ199Hg and Δ200Hg are significantly correlated (R2 = 0.67, P < 0.001, n = 58), consistently oscillating between the modern Hg0 and rainfall HgII end-members. Peat Δ200Hg and Δ199Hg provide evidence of plant uptake of Hg0 as the dominant pathway of Hg deposition to AMS peatland, with some exceptions during humid periods. In contrast to NH archives generally documenting a modern increase in Δ199Hg, recent peat layers (post-1900CE) from AMS show the lowest Δ199Hg in the peat profile (−0.42 ± 0.27 ‰, 1σ, n = 8). This likely reflects a significant change in the post-depositional process on deposited anthropogenic Hg in 20th century (i.e. dark abiotic reduction), enabling more negative Δ199Hg to be observed in AMS peat. We further find that the oscillations of Hg isotopes are consistent with established Holocene climate variability from dust proxies. We suggest peat Hg isotope records might be a valid rainfall indicator.
Keywords: Hg deposition Hg stable isotopes Peat Rain Southern Hemisphere
Programme: 1028
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Marx J.C., Blaise V., Collins T., D'Amico S., Delille D., Gratia E., Hoyoux A., Huston A.ML., Sonan G., Feller G. & Gerday C. (2004). A perspective on cold enzymes: current knowledge and frequently asked questions. Cellular and molecular biology, 50, 643–655.
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Riaux-Gobin C., Klein B. & Duchêne J.C. (2000). A pigment analysis of feeding modes of Thelepus extensus (Polychaeta, Terebellidae) in relation to wave exposure at the Îles Kerguelen. Antarct. Sci., 12(1), 52–63.
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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. (2022). A Possible Alignment Between the Orbits of Planetary Systems and their Visual Binary Companions (Vol. 163).
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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Crosta, X., Gregory, T., Barbara, L., Massé, G., Denis, D., Ther, O. A possible teleconnection between East Antarctic sea ice and ENSO during the Holocene. ISAES 2011, Edinburgh, UK, 10-15 July 2011. (2011). A possible teleconnection between East Antarctic sea ice and ENSO during the Holocene..
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Thiebot JB, Arnould J, Gómez-Laich A, Ito K, Kato A, Mattern T, Mitamura H, Noda T, Poupart T, Quintana F, Raclot T, Ropert-Coudert Y, Sala JE, Sutton G, Yoda K, Takahashi . (2016). A Predator-borne videos emphasize the ecosystem role of jellyfish across southern oceans.
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