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Ancel André, Beaulieu Michaël, Gilbert Caroline, . (2013). The different breeding strategies of penguins: A review
. COMPTES RENDUS BIOLOGIES, 336(1), 1–12.
Abstract: The 18 penguin species are exclusively and widely distributed in the Southern hemisphere, from the Equator to the Antarctic continent, and are thus submitted to various ecological constraints in their reproductive strategy. This results in a high variability in all aspects of the breeding biology of the different species. Although penguins appear primarily adapted for a marine existence, they remain dependent on land for breeding, rearing young, and moulting. Here we describe and compare the breeding cycle of all the penguin species, highlighting the characteristics of each species in terms of breeding range, population status, threats induced by environmental changes, duration of the different phases of the breeding cycle, mate fidelity, body mass, body height, egg mass and duration of egg formation. We also focus on the breeding cycle of the genus Aptenodytes, since it largely differs from the breeding cycle of most of the other penguin species.
Programme: 137
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Ancel André, Cristofari Robin, Fretwell Peter T, Trathan Phil N, Wienecke Barbara, Boureau Matthieu, Morinay Jennifer, Blanc Stéphane, Le Maho Yvon, Le Bohec Céline, . (2014). Emperors in Hiding: When Ice-Breakers and Satellites Complement Each Other in Antarctic Exploration
. PLoS ONE, 9(6), e100404–.
Abstract: Evaluating the demographic trends of marine top predators is critical to understanding the processes involved in the ongoing rapid changes in Antarctic ecosystems. However, the remoteness and logistical complexity of operating in Antarctica, especially during winter, make such an assessment difficult. Satellite imaging is increasingly recognised as a valuable method for remote animal population monitoring, yet its accuracy and reliability are still to be fully evaluated. We report here the first ground visit of an emperor penguin colony first discovered by satellite, but also the discovery of a second one not indicated by satellite survey at that time. Several successive remote surveys in this coastal region of East Antarctica, both before and after sudden local changes, had indeed only identified one colony. These two colonies (with a total of ca. 7,400 breeding pairs) are located near the Mertz Glacier in an area that underwent tremendous habitat change after the glacier tongue broke off in February 2010. Our findings therefore suggest that a satellite survey, although offering a major advance since it allows a global imaging of emperor penguin colonies, may miss certain colony locations when challenged by certain features of polar ecosystems, such as snow cover, evolving ice topology, and rapidly changing habitat. Moreover our survey shows that this large seabird has considerable potential for rapid adaptation to sudden habitat loss, as the colony detected in 2009 may have moved and settled on new breeding grounds. Overall, the ability of emperor penguin colonies to relocate following habitat modification underlines the continued need for a mix of remote sensing and field surveys (aerial photography and ground counts), especially in the less-frequented parts of Antarctica, to gain reliable knowledge about the population demography and dynamics of this flagship species of the Antarctic ecosystem.
Programme: 137
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Ancel André, Gilbert Caroline, Beaulieu Michaël, . (2013). The long engagement of the emperor penguin
. POLAR BIOLOGY, 36(4), 573–577.
Abstract: In birds, courtship is generally short relative to the whole breeding cycle. Emperor penguins (Aptenodytes forsteri), however, are an exception as their courtship period is much longer (ca. 6 weeks) than the courtship of other penguin species. This strategy may appear surprising, as it is especially costly to fast and endure drastic climatic conditions for long periods at the colony (1.5 and up to 4 months for females and males, respectively). We examined here the reasons of this extended courtship period and found that emperor penguins returned earlier to the colony when primary oceanic production before breeding was high. This suggests that emperor penguins return to the colony as soon as primary oceanic production in summer allows them to replenish their body reserves. The extended period of time spent at the colony during courtship may therefore result from an evolutionary process that confers advantages to emperor penguins that arrive earlier at the colony by reducing predation risks and offering better chances of securing a partner.
Keywords: Antarctica, Breeding, Courtship, Ecology, Microbiology, Oceanography, Plant Sciences, Primary oceanic production, Spheniscidae, Zoology,
Programme: 137
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Ancey A. (2019). Analyse échantillons atmosphérique de Concordia.
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Andersen K. K., N. Azuma, J.-M. Barnola, M. Bigler, P. Biscaye, N. Caillon, J. Chappellaz, H. B. Clausen, D. Dahl-Jensen, H. Fischer, J. Flückiger, D. Fritzsche, Y. Fujii, K. Goto-Azuma, K. Grønvold, N. S. Gundestrup, M. Hansson, C. Huber, C. S. Hvidberg, S. J. Johnsen, U. Jonsell, J. Jouzel, S. Kipfstuhl, A. Landais, M. Leuenberger, R. Lorrain, V. Masson-Delmotte, H. Miller, H. Motoyama, H. Narita, T. Popp, S. O. Rasmussen, D. Raynaud, R. Rothlisberger, U. Ruth, D. Samyn, J. Schwander, H. Shoji, M.-L. Siggard-Andersen, J. P. Steffensen, T. Stocker, A. E. Sveinbjörnsdóttir, A. Svensson, M. Takata, J.-L. Tison, Th. Thorsteinsson, O. Watanabe, F. Wilhelms & J. W. C. White. (2005). High resolution climate record of the northern hemisphere reaching into last interglacial period. Nature, 431, 147–151.
Abstract: Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from a North Greenland ice core, which extends back to 123,000 years before the present, within the last interglacial period. The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 °C warmer than today. We find unexpectedly large temperature differences between our new record from northern Greenland and the undisturbed sections of the cores from central Greenland, suggesting that the extent of ice in the Northern Hemisphere modulated the latitudinal temperature gradients in Greenland. This record shows a slow decline in temperatures that marked the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see-saw between the hemispheres (which dominated the last glacial period) was not operating at this time.
Programme: 458
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Andersen, O.B.; Hinderer, J. (2005). Global inter-annual gravity changes from GRACE: Early results. Geophysical research letters, 32.
Abstract: Fifteen monthly gravity field solutions from the GRACE twin satellites launched more than two years ago have been studied to estimate gravity field changes between 2002 and 2003.The results demonstrate that GRACE is capable of capturing the changes in ground water on inter-annual scales with an accuracy of 0.4 ?Gal corresponding to 9 mm water thickness on spatial scales longer than 1300 km. Four of the most widely used global hydrological models have been investigated for their spatial comparison with GRACE observations of inter-annual gravity field variations due to changes in continental water storage. The Global Land Data Assimilation System model has a spatial correlation coefficient with GRACE observations of 0.65 over the northern hemisphere. This demonstrates that the observed gravity field changes on these scales are largely related to changes in continental water storage.
Keywords: 1217 Geodesy and Gravity: Time variable gravity; 1855 Hydrology: Remote sensing; 1640 Global Change: Remote sensing; 1655 Global Change: Water cycles
Programme: 337
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Andersen, O.B.; Seneviratne, S.I.; Hinderer, J.; Viterbo, P. (2005). GRACE-derived terrestrial water storage depletion associated with the 2003 European heat wave. Geophysical research letters, 32.
Abstract: The GRACE twin satellites reveal large inter-annual terrestrial water-storage variations between 2002 and 2003 for central Europe. GRACE observes a negative trend in regional water storage from 2002 to 2003 peaking at ?7.8 cm in central Europe with an accuracy of 1 cm. The 2003 excess terrestrial water storage depletion observed from GRACE can be related to the record-breaking heat wave that occurred in central Europe in 2003. We validate the measurements from GRACE using two independent hydrological estimates and direct gravity observations from superconducting gravimeters in Europe. All datasets agree well with the GRACE measurements despite the disparity of the employed information; the difference between datasets tends to be within GRACE margin of error. The April-to-August terrestrial water storage depletion is found to be significantly larger in 2003 than in 2002 from both models and observations.
Keywords: 1640 Global Change: Remote sensing; 1655 Global Change: Water cycles; 1836 Hydrology: Hydrological cycles and budgets; 1812 Hydrology: Drought
Programme: 337
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André F., P. Téchiné, G. Alory, J. Llido. (2019). Bilan d'activités et prospectives du CDS-IS OMP.
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André G., B. Martin Miguez, V. Ballu, L. Testut, G. Wöppelmann, P. Tiphaneau. (2014). La mesure du niveau de la mer par bouées GPS : l’expérience multi-capteurs de l’île d’Aix..
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André G., B. Martin Miguez, V. Ballu, L. Testut, G. Wöppelmann, P. Tiphaneau. (2014). La mesure du niveau de la mer par bouées GPS : l’expérience multi-capteurs de l’île d’Aix.
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