Abstract: In the context of long and continuous time–series photometry and after the MOST, CoRoT, KEPLER space missions and large geographic longitude ground–based networks, a new method is offered by the polar location helping to cope with the problem associated with the Earth’s day–night cycle. In this talk, we present the first long time–series photometry from the heart of Antarctica -Dome Charlie- and we discuss briefly our new results and perspective on the pulsating stars from Antarctica, especially the connection between temporal hydrodynamic phenomena and cyclic modulations. Finally, we highlight the impact of PAIX -the robotic Antarctica photometer- on the stellar pulsation study.

Abstract: This paper addresses the problem of rigid body orientation and Dynamic Body Acceleration (DBA) estimation. This work is applied in bio-logging, an interdisciplinary research area at the intersection of animal behavior and bioengineering. The proposed approach combines a quaternion-based nonlinear filter with the Levenberg Marquardt Algorithm (LMA). The algorithm has a complementary structure design that exploits measurements from a three-axis accelerometer, a three-axis magnetometer, and a three-axis gyroscope. Attitude information is necessary to calculate the animal's DBA in order to evaluate its energy expenditure. Some numerical simulations illustrate the nonlinear filter performance. Some quantitative assessments prove this efficiency such as the time constant of the filter ( ) and the rms magnitude of the quaternion error ( ). Moreover, the effectiveness of the algorithm is experimentally demonstrated. In the experiments a domestic animal is equipped with an Inertial Measurement Unit (MTi-G), which provides a truth attitude for comparison with the complementary nonlinear filter. The rms difference between the filter and MTi-G outputs in the free movement experiments is within 0.392 rms on roll, 0.577 rms on pitch, and 2.521 rms on yaw.

Abstract: Despite expanding in-situ observations of marine ecosystems by new-generation sensors, information about intermediate trophic levels remains sparse. Indeed, mid-trophic levels, while encompassing a broad range of zooplankton and micronekton organisms that represent a key component of marine ecosystems and sustain large and diverse communities of marine predators, are challenging to sample and identify. In this study, we examined whether an animal-borne miniature active echosounder can provide information on the distribution and movements of mid-trophic level organisms. If so, such a sonar tag, harnessing the persistent diving behaviour of far-ranging marine mammals, could greatly increase the density of data on this under-studied biome. High-frequency (1.5 MHz) sonar tags were deployed simultaneously with oceanographic tags on two southern elephant seals (Mirounga leonina), at the Kerguelen Islands and Valdés Peninsula (Argentina), and recorded acoustic backscatter while the seals foraged respectively in the Indian and the Atlantic sectors of the Southern Ocean. The backscatter varied widely over time and space, and the seals attempted to capture only a small fraction of the insonified targets. Diel vertical migration patterns were clearly identifiable in the data, reinforcing our confidence in the ability of the sonar tags to detect living mid-trophic organisms along with possibly sinking biological detritus. Moreover, CTD tags attached to the same animals indicated how the abundance, size distribution, and diel migration behaviour of acoustic targets varied with water bodies. These preliminary results demonstrate the potential for animal-borne sonars to provide detailed in-situ information. Further validation effort will make it a valuable tool to refine the estimation of carbon export fluxes as well as for assessing the variation of mid-trophic level biomass according to oceanographic domains and seasons.

Abstract: None of the previous aeolian snow transport campaigns in Antarctica meet the requirements in terms of temporal resolution, long-term series and qualified instruments for evaluations of meteorological and climate models including parameterization for aeolian snow transport. Consequently, determining the quantity of snow transported remains a challenge. A field campaign was therefore launched in January 2009, in Adélie Land, Antarctica, to acquire new model-evaluation-oriented observations within the European ICE2SEA project, with the logistical support of the French polar Institute (IPEV). The available aeolian snow transport sensors are reviewed and the sensor that best suited our specific needs was chosen: FlowCapt™ acoustic sensors. Three automatic weather stations were deployed with FlowCapts™ close to the coast. The stations' locations are distinct, ranging from 1 to 100km inland, one of them with a 7-m mast with six levels of anemometers and thermohygrometers. The fluid and impact threshold friction velocities recorded were 0.48±0.09ms−1 and 0.4±0.09ms−1, respectively, with a high standard deviation of 0.12±0.03ms−1 and 0.13±0.03ms−1, respectively. The aeolian snow transport frequency in Adélie Land was very high with seasonal variation of transport occurring with minima during the austral summer. Seven percent of the aeolian snow transport events were drifting snow (maximum particle's height, <1m above the surface). The snow quantity transported was above 1kiloton per year in the first meter above the surface.