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Dommergue Aurelien, Larose Catherine, Fain Xavier, Clarisse Olivier, Foucher Delphine, Hintelmann Holger, Schneider Dominique, Ferrari Christophe P,. (2010). Deposition of Mercury Species in the Ny-Ålesund Area (79°N) and Their Transfer during Snowmelt. Environ. Sci. Technol., 44(3), 901–907.
Abstract: Arctic snowpacks are often considered as temporary reservoirs for atmospheric mercury (Hg) deposited during springtime deposition events (AMDEs). The fate of deposited species is of utmost importance because melt leads to the transfer of contaminants to snowmelt-fed ecosystems. Here, we examined the deposition, fate, and transfer of mercury species (total Hg (THg) and methylmercury (MeHg)) in an arctic environment from the beginning of mass deposition of Hg during AMDEs to the full melt of the snow. Following these events, important amounts of THg were deposited onto the snow surface with concentrations reaching 373 ng·L-1 and estimated deposition fluxes of 200-2160 ng·m-2. Most of the deposited Hg was reemitted to the atmosphere via photochemical reactions. However, a fraction remained stored in the snow and we estimated that the spring melt contributed to an input of 1.5-3.6 kg·year-1 of THg to the fjord (i.e., 8-21% of the fjord’s THg content). A monitoring of MeHg in snow using a new technique (DGT sensors) is also presented.
Programme: 399
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Nesterova Anna, Le Bohec Céline, Beaune David, Pettex Emeline, Le Maho Yvon, Bonadonna Francesco, . (2010). Do penguins dare to walk at night? Visual cues influence king penguin colony arrivals and departures
. Behav. Ecol. Sociobiol. (Print), 64(7), 1145–1156.
Abstract: Orientation based on visual cues can be extremely difficult in crowded bird colonies due to the presence of many individuals. We studied king penguins (Aptenodytes patagonicus) that live in dense colonies and are constantly faced with such problems. Our aims were to describe adult penguin homing paths on land and to test whether visual cues are important for their orientation in the colony. We also tested the hypothesis that older penguins should be better able to cope with limited visual cues due to their greater experience. We collected and examined GPS paths of homing penguins. In addition, we analyzed 8 months of penguin arrivals to and departures from the colony using data from an automatic identification system. We found that birds rearing chicks did not minimize their traveling time on land and did not proceed to their young (located in crèches) along straight paths. Moreover, breeding birds' arrivals and departures were affected by the time of day and luminosity levels. Our data suggest that king penguins prefer to move in and out of the colony when visual cues are available. Still, they are capable of navigating even in complete darkness, and this ability seems to develop over the years, with older breeding birds more likely to move through the colony at nighttime luminosity levels. This study is the first step in unveiling the mysteries of king penguin orientation on land.
Keywords: Biomedical and Life Sciences,
Programme: 137;354
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Bonadonna Francesco, Mardon Jérôme, . (2010). One House Two Families: Petrel Squatters Get a Sniff of Low-Cost Breeding Opportunities
. Ethology, 116(2), 176–182.
Abstract: Summary Burrowing is a widespread nesting behaviour, found in vertebrates and invertebrates. It is particularly common in small procellariiform seabirds such as blue petrels (Halobaena caerulea) and Antarctic prions (Pachyptila desolata), two closely related petrel species. However, digging a burrow is costly and alternative strategies may evolve. Accordingly, blue petrel males can adopt two alternative nesting strategies: digging a new burrow or squatting in an empty one. Importantly, a blue petrel squatter arriving at the colony to breed is more likely to find empty Antarctic prion burrows than empty blue petrel burrows, since the former species only start breeding a month later. However, squatting in a prions burrow is risky for blue petrels as the legitimate owner very often returns and claims the burrow back, thus ruining the squatters breeding attempt. We present here results of a survey of two sympatric colonies of blue petrels and Antarctic prions on Kerguelen Island. Our data show that blue petrel squatters preferentially occupy blue petrel empty burrows. To investigate potential underlying mechanisms behind this preference, we used a simple Y-maze design to show that blue petrels can discriminate and prefer their specific odour over the prion odour. Our results confirm the existence of alternative burrowing strategies in blue petrels and suggest that squatters could use olfaction to avoid the less suitable Antarctic prion burrows.
Programme: 354
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Ricaud, P., S. Derrien, J.-P. Chaboureau, J.-L. Attié, T. Rose, H. Czekala, C. Genthon, L. Genoni, A. Pellegrini and G. Durand. (2010). The 183-GHz Radiometer HAMSTRAD: first measurements of Temperature and Humidity in the PBL at Dome C (Antarctica), (Vol. ISARS 2010 Symposium, Paris, June 2010.). Bachelor's thesis, , .
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Rabier Florence, Bouchard Aurélie, Brun Eric, Doerenbecher Alexis, Guedj Stéphanie, Guidard Vincent, Karbou Fatima, Peuch Vincent-Henri, Amraoui Laaziz El, Puech Dominique, Genthon Christophe, Picard Ghislain, Town Michael, Hertzog Albert, Vial François, Cocquerez Philippe, Cohn Stephen A, Hock Terry, Fox Jack, Cole Hal, Parsons David, Powers Jordan, Romberg Keith, VanAndel Joseph, Deshler Terry, Mercer Jennifer, Haase Jennifer S, Avallone Linnea, Kalnajs Lars, Mechoso C Roberto, Tangborn Andrew, Pellegrini Andrea, Frenot Yves, Thépaut Jean-Noël, McNally Anthony, Balsamo Gianpaolo, Steinle Peter, . (2010). The Concordiasi Project in Antarctica
. BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY, 91(1), 69–85.
Abstract: Abstract The Concordiasi project is making innovative observations of the atmosphere above Antarctica. The most important goals of the Concordiasi are as follows: To enhance the accuracy of weather prediction and climate records in Antarctica through the assimilation of in situ and satellite data, with an emphasis on data provided by hyperspectral infrared sounders. The focus is on clouds, precipitation, and the mass budget of the ice sheets. The improvements in dynamical model analyses and forecasts will be used in chemical-transport models that describe the links between the polar vortex dynamics and ozone depletion, and to advance the understanding of the Earth system by examining the interactions between Antarctica and lower latitudes.To improve our understanding of microphysical and dynamical processes controlling the polar ozone, by providing the first quasi-Lagrangian observations of stratospheric ozone and particles, in addition to an improved characterization of the 3D polar vortex dynamics. Tech...
Programme: 1013
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Trouvilliez A. (2010). Modélisation et quantification de, la neige soufflée en Antarctique, . Bachelor's thesis, , .
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OZOUF-COSTAZ C. (2009). Recherches extrêmes sur une vie extrême : les notions de biodiversité et d’adaptaton aux milieux. Bachelor's thesis, , .
Abstract: Forum des Sciences franco-allemand. Cit des Sciences et de l’Industrie, 19-21 mars 2009.
Programme: 1124
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Houssais, M.-N. (2008). Albion : une étude de la formation des eaux de fond océaniques à partir de mesures de terrain réalisées à bord de l’ASTROLABE. Séminaire des VCATs et des contractuels TA, IPEV, Brest, 16-18 September, 2008. Bachelor's thesis, , .
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Fourati H, Manamanni N, Afilal L, Handrich Y, . (2009). A rigid body attitude estimation for Bio-logging application: A quaternion-based nonlinear filter approach
. Bachelor's thesis, IEEE, .
Abstract: Bio-logging is a new interdisciplinary research area at the intersection of animal behavior and bioengineering. It involves several applications such as determination of specific parameters (attitude, acceleration, and position) via a new generation of mechatronic systems. The aim of this paper concerns the animal motion estimation problem using low-cost sensors fusion. A quaternion-based nonlinear observer for the tracking of rigid body attitude (orientation) and heading using measurements provided from low cost inertial and magnetic sensors is presented. The algorithm combines low-frequency, 3-axis accelerometer and 3-axis magnetometer, data with high frequency 3-axis gyroscope measurement. Then, to increase the performance and reduce the computational requirements, we exploit the sensor readings directly in the designed observer. Using the estimated attitude, the linear acceleration is then derived. This latter will be used in the future to evaluate the animal energy index and its mechanical work. Finally, some experimental results, using the measurements provided by an inertial sensor put on dog are given to illustrate the efficiency of the proposed algorithm.
Programme: 394
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V. Korepanov, A. Marusenkov, A. Chambodut, J.-J. Schott. (2010). Observatory magnetometer in-situ calibration. Bachelor's thesis, , .
Abstract: XIVth IAGA WORKSHOP ON GEOMAGNETIC OBSERVATORY INSTRUMENTS, DATA ACQUISITION AND PROCESSING; September 13 – 23, 2010; Changchun, Jilin Province, China.
The magnetic observatories are continuously striving to improve the accuracy of the field measurements. A renewed interest came up recently for instruments using a scalar sensor placed into the center of a coil system (see references below). They are able to reach very high accuracy , but at the expense of relatively high own noise background. So far, the majority of the observatories are still equipped by flux-gate or even photoelectric variometers. The baseline of these types of variometers are estimated using well-known absolute measurements, whereas the scale factors and orientation of the sensor reference frame, which are implicitly involved into the computation of the absolutes values of the field, usually are poorly known and almost everywhere not calibrated periodically, as should be required. The absence of the periodical calibration can be partly explained by fact that the metrological certification of the instruments should be provided in special laboratory by means of calibrations coils what requires to interrupt the measurements, transport the instrument to and from the calibration site and reinstall it again in the observatory. This way of doing is absolutely unacceptable, especially for remote observatories, because the time taken by the whole procedure can be very long, resulting in large gaps in the records. There is also a calibration method based upon magnetometer rotation in the approximately constant Earth’s magnetic field. However, whereas this method gives acceptable precision for, e.g., satellite magnetometers, it is not applicable to observatory magnetometers, due to the actual limited range of field variation, the large relative errors and the possibly unequal scale factors. In addition, the issue of the in-situ orientation of the triaxial magnetometer remains unsolved if we are seeking high accuracy.
In this report we continue to discuss the possibility to calibrate in-situ the observatory instrument based upon the comparison of its records with the field recorded simultaneously by a reference magnetometer. The certified reference instrument has to be installed close to the tested one, its sensitivity axes properly oriented with respect to the geomagnetic frame and the records as synchronous as possible.
The improved version of the observatory magnetometer LEMI-025 was specially designed as a reference instrument. In order to check practical aspects of the proposed in-situ calibration procedure two such magnetometers calibrated using a reference coil facility have been installed in the Strasbourg University geophysical station for intercalibration. The results obtained by processing synchronous records as well as the reliability of these results and estimations of the errors involved into the in-situ calibration procedure are discussed.
Programme: 139;905
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