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O. Alemany, P. Talalay, P. Boissonneau, J. Chappellaz, J. F. Chemin, R. Duphil, E. Lefebvre, L. Piard, P. Possenti, J. Triest. (2021). The SUBGLACIOR drilling probe: hydraulic considerations (Vol. 62).
Abstract: Using significant technological breakthroughs and unconventional approaches, the goal of the in situ probing of glacier ice for a better understanding of the orbital response of climate (SUBGLACIOR) project is to advance ice core research by inventing, constructing and testing an in situ probe to evaluate if a target site is suitable for recovering ice as old as 1.5 million years. Embedding a laser spectrometer, the probe is intended to make its own way down into the ice and to measure, in real time and down to the bedrock, the depth profiles of the ice ?D water isotopes as well as the trapped CH4 gas concentration and dust concentration. The probe descent is achieved through electromechanical drilling combined with continuous meltwater sample production using a central melting finger in the drill head. A key aspect of the project lies in the design and implementation of an efficient method to continuously transfer to the surface the ice chips being produced by the drill head and from the refreezed water expulsed downstream from the melting finger, into the borehole. This paper presents a detailed calculation and analysis of the flow rates and pressure conditions required to overcome friction losses of the drilling fluid and to effectively transport ice chips to the surface.
Keywords: Glaciological instruments and methods ice coring ice engineering paleoclimate
Programme: 119
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C. Tape, Q. Liu, A. Maggi, J. Tromp. (2009). Adjoint tomography of the southern California crust. Science, 325, 988–992.
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. (2009). Quake Catalogs from an Optical Monitoring of an Interfacial Crack Propagation
. Pure and Applied Geophysics, 166(5-7), 777–799.
Abstract: Using an experimental setup which allows to follow optically the propagation of an interfacial crack front in a heterogeneous medium, we show that the fracture front dynamics is governed by local and irregular avalanches with large velocity fluctuations. Events defined as high velocity bursts are ranked in catalogs with analogous characteristics to seismicity catalogs: time of occurence, epicenter location and energy parameter (moment). Despite differences in the fracturing mode (opening for the experiments and shear rupture for earthquakes), in the acquisition mode and in the range of time scales, the distributions of moment and epicenter jumps in the experimental catalogs obey the same scaling laws with exponents similar to the corresponding distributions for earthquakes. The record-breaking event analysis also shows very strong similarities between experimental and real seismicity catalogs. The results suggest that the dynamics of crack propagation is controlled by the elastic interactions between microstructures within the material.
Keywords: Earth and Environmental Science,
Programme: 133
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Brun Eric, Six Delphine, Picard Ghislain, Vionnet Vincent, Arnaud Laurent, Bazile Eric, Boone Aaron, Bouchard Aurelie, Genthon Christophe, Guidard Vincent, Le Moigne Patrick, Rabier Florence, Seity Yann, . (2011). Snow/atmosphere coupled simulation at Dome C, Antarctica
. Journal of Glaciology, 57(204), 721–736.
Abstract: Using a snow/atmosphere coupled model, the evolution of the surface and near-surface snow temperature is modeled at Dome C, Antarctica, during the period 20-30 January 2010. Firstly, the detailed multilayer snow model Crocus is run in stand-alone mode, with meteorological input forcing data provided by local meteorological observations. The snow model is able to simulate the evolution of surface temperature with good accuracy. It reproduces the observed downward propagation of the diurnal heatwave into the upper 50 cm of the snowpack reasonably well. Secondly, a fully coupled 3-D snow/atmosphere simulation is performed with the AROME regional meteorological model, for which the standard single-layer snow parameterization is replaced by Crocus. In spite of a poor simulation of clouds, the surface and near-surface snow temperatures are correctly simulated, showing neither significant bias nor drifts during the simulation period. The model reproduces particularly well the average decrease of the diurnal amplitude of air temperature from the surface to the top of the 45 m instrumented tower. This study highlights the potential of snow/atmosphere coupled models over the Antarctic plateau and the need to improve cloud microphysics and data assimilation over polar regions.
Programme: 1013
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. (2013). Pelagic cephalopods in the western Indian Ocean: New information from diets of top predators
. Deep Sea Res. Part II Top. Stud. Oceanogr., 95, 83–92.
Abstract: Using a combination of diverse large predatory fishes and one seabird, we collected information on the cephalopod fauna of the western Indian Ocean. We analyzed the stomach contents of 35 fishes representing ten families (Xiphiidae, Istiophoridae, Scombridae, Carangidae, Coryphaenidae, Alepisauridae, Dasyatidae, Carcharhinidae, Alopiidae and Sphyrnidae) and of the sooty tern Onychoprion fuscata of the Mozambique Channel from 2000 to 2010. Both fresh and accumulated beaks were used for identifying cephalopod prey. Cephalopods were important prey for twelve predators; swordfish Xiphias gladius had the highest cephalopod proportion; sooty tern (O. fuscata) and bigeye tuna (Thunnus obesus) had high proportions too. We recovered 23 cephalopod families and identified 38 species. Ten species from four Teuthida families (Ommastrephidae, Onychoteuthidae, Histioteuthidae and Ancistrocheiridae) and two Octopoda families (Argonautidae and Bolitaenidae) occurred very frequently in the stomach contents, while Sepiida were rare. Ommastrephidae were the most cephalopod food sources: the purpleback flying squid Sthenoteuthis oualaniensis was the most prevalent prey by far, Ornithoteuthis volatilis was important for eleven predators and few but large specimens of the neon flying squid Ommastrephes bartramii were recovered in the stomachs of swordfish in the Indian South Subtropical Gyre province only. Predators' groups were identified based on cephalopod prey composition, on depth in which they forage, and on prey size. Surface predators' diets were characterized by lower cephalopod diversity but greater average numbers of cephalopod prey, whereas the deep-dwelling predators (swordfish and bigeye tuna) preyed on larger specimens than surface predators (O. fuscata or yellowfin tunas Thunnus albacares). Our findings emphasized the usefulness of a community of marine predators to gain valuable information on the biology and the distribution of the cephalopod forage fauna that are discussed with regard to biogeographic province, marine predator, fishing gear to catch the large pelagic fishes, and size of the beaks recovered in the stomachs.
Keywords: Beaks, Diet composition, Octopod, Ommastrephidae, Pelagic fish, Sooty tern, Squid, Trophic ecology,
Programme: 109
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Clementi C. & Morinais G. (1999).
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Johannes H. Fischer, Igor Debski, Colin M. Miskelly, Charles A. Bost, Aymeric Fromant, Alan J. D. Tennyson, Jake Tessler, Rosalind Cole, Johanna H. Hiscock, Graeme A. Taylor, Heiko U. Wittmer. (2018). Analyses of phenotypic differentiations among South Georgian Diving Petrel (Pelecanoides georgicus) populations reveal an undescribed and highly endangered species from New Zealand (Vol. 13).
Keywords: Biometrics Birds Ears Islands New Zealand Principal component analysis Species delimitation Taxonomy
Programme: 394
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. (2015). Approaching birds with drones: first experiments and ethical guidelines.
. Biology letters, 11(2), 20140754.
Abstract: Unmanned aerial vehicles, commonly called drones, are being increasingly used in ecological research, in particular to approach sensitive wildlife in inaccessible areas. Impact studies leading to recommendations for best practices are urgently needed. We tested the impact of drone colour, speed and flight angle on the behavioural responses of mallards Anas platyrhynchos in a semi-captive situation, and of wild flamingos (Phoenicopterus roseus) and common greenshanks (Tringa nebularia) in a wetland area. We performed 204 approach flights with a quadricopter drone, and during 80% of those we could approach unaffected birds to within 4 m. Approach speed, drone colour and repeated flights had no measurable impact on bird behaviour, yet they reacted more to drones approaching vertically. We recommend launching drones farther than 100 m from the birds and adjusting approach distance according to species. Our study is a first step towards a sound use of drones for wildlife research. Further studies should assess the impacts of different drones on other taxa, and monitor physiological indicators of stress in animals exposed to drones according to group sizes and reproductive status.
Keywords: Aircraft, Aircraft: ethics, Aircraft: instrumentation, Animals, Behavior, Animal, Charadriiformes, Charadriiformes: physiology, Color, Ducks, Ducks: physiology, Remote Sensing Technology, Remote Sensing Technology: ethics, Remote Sensing Technology: instrumentation,
Programme: 388
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. (2017). Implantation of subcutaneous heart rate data loggers in southern elephant seals (Mirounga leonina) (Vol. 40).
Keywords: Marine mammals Pinnipeds Surgery
Programme: 1201
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Renault D. (2008). Assessing the vulnerability of native communities to invasive species and climate change: subantarctic islands.
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