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Weisenhorn G., E. Pamba Capo-Chichi, J.-M. Friedt. (2007). Communications de données et d'images issues de la carte Fox par Bluetooth, GNU/Linux Magazine France 95, Juin 2007.
Abstract: publié dans Linux Magazine
Programme: 304
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Weisen Shen, Douglas A. Wiens, Sridhar Anandakrishnan, Richard C. Aster, Peter Gerstoft, Peter D. Bromirski, Samantha E. Hansen, Ian W. D. Dalziel, David S. Heeszel, Audrey D. Huerta, Andrew A. Nyblade, Ralph Stephen, Terry J. Wilson, J. Paul Winberry. (2018). The Crust and Upper Mantle Structure of Central and West Antarctica From Bayesian Inversion of Rayleigh Wave and Receiver Functions (Vol. 123).
Abstract: We construct a new seismic model for central and West Antarctica by jointly inverting Rayleigh wave phase and group velocities along with P wave receiver functions. Ambient noise tomography exploiting data from more than 200 seismic stations deployed over the past 18 years is used to construct Rayleigh wave phase and group velocity dispersion maps. Comparison between the ambient noise phase velocity maps with those constructed using teleseismic earthquakes confirms the accuracy of both results. These maps, together with P receiver function waveforms, are used to construct a new 3-D shear velocity (Vs) model for the crust and uppermost mantle using a Bayesian Monte Carlo algorithm. The new 3-D seismic model shows the dichotomy of the tectonically active West Antarctica (WANT) and the stable and ancient East Antarctica (EANT). In WANT, the model exhibits a slow uppermost mantle along the Transantarctic Mountains (TAMs) front, interpreted as the thermal effect from Cenozoic rifting. Beneath the southern TAMs, the slow uppermost mantle extends horizontally beneath the traditionally recognized EANT, hypothesized to be associated with lithospheric delamination. Thin crust and lithosphere observed along the Amundsen Sea coast and extending into the interior suggest involvement of these areas in Cenozoic rifting. EANT, with its relatively thick and cold crust and lithosphere marked by high Vs, displays a slower Vs anomaly beneath the Gamburtsev Subglacial Mountains in the uppermost mantle, which we hypothesize may be the signature of a compositionally anomalous body, perhaps remnant from a continental collision.
Keywords: ambient noise tomography Antarctica crust and uppermost mantle Gamburtsev Mountains seismology Transantarctic Mountains
Programme: 133
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Weisen Shen, Douglas A. Wiens, Andrew J. Lloyd, Andrew A. Nyblade. (2020). A Geothermal Heat Flux Map of Antarctica Empirically Constrained by Seismic Structure (Vol. 47).
Abstract: The geothermal heat flux (GHF) is an important boundary condition for modeling the movement of the Antarctic ice sheet but is difficult to measure systematically at a continental scale. Earlier GHF maps suffer from low resolution and possibly biased assumptions in tectonism and crustal heat generation, resulting in significant uncertainty. We present a new GHF map for Antarctica constructed by empirically relating the upper mantle structure to known GHF in the continental United States. The new map, compared with previously seismologically determined one, has improved resolution and lower uncertainties. New features in this map include high GHF in the southern Transantarctic Mountains where warmer uppermost mantle is introduced by lithospheric removal and in the Thwaites Glacier region. Additionally, a modest GHF in the central West Antarctic Rift system near the Siple Coast and an absence of large-scale regions with GHF greater than 90 mW/m2 are found.
Keywords: Antarctica crust and uppermost mantle geothermal heat flux ice sheet modeling
Programme: 133
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Weis D., Frey F.A., Giret A. & Cantagrel J.M. (1998). Geochemical Characteristics of the Youngest Volcano (Mount Ross) in the Kerguelen Archipelago: Inferences for Magma Flux, Lithosphere assimilation and Composition of the Kerguelen Plume. Journal of petrology, 39, 973–994.
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Weis D., Damasceno D., Fey F.A., Nicolaysen K. & Giret A. (1998). Temporal Isotopic Variations in the Kerguelen Plume: Evidence from the Kerguelen Archipelago..
Abstract: Workshop 'Progress in Kerguelen Islands Geology'
Programme: 251
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Weis D. & Giret A. (1994). Kerguelen plutonic complexes : Sr, Nd, Pb isotonic study and inferences about their sources, age and geodynamic setting. Memoires de la societe geologique de france, 166, 47–59.
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Weimerskirch, H.; Cherel, Y.; Cuenot-Chaillet, F.; Ridoux, V. (1997). Alternative foraging strategies and resource allocation by male and female wandering albatrosses. Ecology, 78(7), 2051–2063.
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Weimerskirch, H., Pinaud, D, Pawlowski, F. & Bost, CA. (2007). Does Prey Capture Induce Area-Restricted Search? A Fine-Scale Study Using GPS in a Marine Predator,the Wandering Albatross capture and GPS. Am. Nat., 170(5), 735–743.
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Weimerskirch Henri, Louzao Maite, de Grissac Sophie, Delord Karine, . (2012). Changes in Wind Pattern Alter Albatross Distribution and Life-History Traits
. Science, 335 (6065 ), 211–214 .
Abstract: Westerly winds in the Southern Ocean have increased in intensity and moved poleward. Using long-term demographic and foraging records, we show that foraging range in wandering albatrosses has shifted poleward in conjunction with these changes in wind pattern, while their rates of travel and flight speeds have increased. Consequently, the duration of foraging trips has decreased, breeding success has improved, and birds have increased in mass by more than 1 kilogram. These positive consequences of climate change may be temporary if patterns of wind in the southern westerlies follow predicted climate change scenarios. This study stresses the importance of foraging performance as the key link between environmental changes and population processes.
Programme: 109
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Weimerskirch Henri, Delord Karine, Guitteaud Audrey, Phillips Richard A, Pinet Patrick, . (2015). Extreme variation in migration strategies between and within wandering albatross populations during their sabbatical year, and their fitness consequences.
. Scientific reports, 5, 8853.
Abstract: Migratory behavior, routes and zones used during the non-breeding season are assumed to have been selected to maximize fitness, and can lead to genetic differentiation. Yet, here we show that migration strategies differ markedly between and within two genetically similar populations of wandering albatross Diomedea exulans from the Crozet and Kerguelen archipelagos in the Indian Ocean. Wandering albatrosses usually breed biennially if successful, and during the sabbatical year, all birds from Kerguelen migrate to the Pacific Ocean, whereas most from Crozet are sedentary. Instead of taking the shortest routes, which would involve a return against headwinds, migratory birds fly with the westerly winds, requiring detours of 10,000 s km. In total, migrants circumnavigate Antarctica 2 to 3 times, covering more than 120,000 km in a single sabbatical year. Our results indicate strong links between migratory behavior and fitness; all birds from Kerguelen breed biennially, whereas a significant proportion of those from Crozet, especially females, are sedentary and breed in consecutive calendar years. To breed annually, these females temporarily change mate, but return to their original partner in the following year. This extreme variation in migratory behavior has important consequences in term of life history evolution and susceptibility to climate change and fisheries.
Programme: 109
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