Abstract: A small-size meteorological mast, BEAR (Budget of Energy for Arctic regions) has been developed as a part of a new autonomous buoy for monitoring the sea ice mass balance. BEAR complements observations of the thickness and thermodynamic properties of the ice/snow pack determined by the so-called Ice-T (Ice-Thickness) buoy, giving access to bulk fluxes and energy budget at the surface, using meteorological measurements. The BEAR mast has been tested with success during ten days in April-May 2010 at Ny Alesund, in the Svalbard archipelago (Norway) showing that meteorological data were close to measurements at the same level of the Italian Climate Change Tower (CCT) from the ISAC-CNR. A discussion is undertaken on bulk fluxes determination and uncertainties. Particularly, the strategy to systematically use different relevant fluxes parameterizations is pointed out to explore flux range uncertainty before to analyze energy budget. Net radiation, bulk fluxes and energy budget are estimated using as average 10 minutes, 24 hours and the ten days of the experiment. The observation period was very short, but we observe a spring transition when the net radiation begins to warm the surface while the very small turbulent heat flux cools the surface.

Abstract: The sub-Antarctic islands of the Southern Ocean harbor biogeographically peculiar biotas which are under threat from climate change, biological invasions and their interactions. Understanding both the indigenous and changing non-indigenous components of these islands is essential for the conservation and management of their biotas. Based on several years of systematic sampling, we present an updated list of terrestrial, free-living macro-invertebrates (insects and spiders) present on the islands of Possession (Crozet Archipelago) and Kerguelen. Ninety-four species were recorded in total on both islands. Forty-one are strictly endemic to one of the two islands, 16 are endemic to the South Indian Ocean Province, and only three were recorded on other sub-Antarctic islands. Beetles and more particularly weevils are the most characteristic group of the fauna of these islands: they include 35 species of which 89% are native and 66% are endemic. One third of the species (30 of 94) are non-indigenous species now naturalized. We discuss these results in terms of biogeography, ecological disharmony and impact of biological invasions.

Abstract: Thanks to its high nutritional potential and huge ivory canines, walrus (Odobenus rosmarus) appears to have been a key resource in the subsistence economy of Dorset groups. However present archaeological data are sparse and a more global analysis of its exploitation by the Palaeoeskimos is required. The Tayara site (KbFk-7) in Nunavik (Quebec, Canada) yielded a significant assemblage of walrus bones and many manufactured ivory objects. In addition, Tayara serves as a reference site in Eastern Arctic cultural chronology. A thorough zooarchaeological study has been conducted which includes skeletal profile, the sexing and ageing of walrus bones, and a technological study of the manufactured objects, including a use-wear analysis on lithic tools. This allows the discussion of several aspects of the modus operandi for the exploitation of walrus, from the death of the animal to the processing of the raw material into artefacts. Even if the walrus seems to have been treated with the same processes as other species, some specificities have been noted, particularly in the selection of the different skeletal elements for tool productions and the emblematic value that this animal may have played in consumption and production activities.

Abstract: A new comprehensive cloud-precipitation-meteorological observatory has been established at Princess Elisabeth base, located in the escarpment zone of Dronning Maud Land, East Antarctica. The observatory consists of a set of ground-based remote sensing instruments (ceilometer, infrared pyrometer and vertically profiling precipitation radar) combined with automatic weather station measurements of near-surface meteorology, radiative fluxes, and snow accumulation. In this paper, the observatory is presented and the potential for studying the evolution of clouds and precipitating systems is illustrated by case studies. It is shown that the synergetic use of the set of instruments allows for distinguishing ice, mixed-phase and precipitating clouds, including some information on their vertical extent. In addition, wind-driven blowing snow events can be distinguished from deeper precipitating systems. Cloud properties largely affect the surface radiative fluxes, with liquid-containing clouds dominating the radiative impact. A statistical analysis of all measurements (in total 14 months mainly occurring in summer/autumn) indicates that these liquid-containing clouds occur during as much as 20% of the cloudy periods. The cloud occurrence shows a strong bimodal distribution with clear sky conditions 51% of the time and complete overcast conditions 35% of the time. Snowfall occurred 17% of the cloudy periods with a predominance of light precipitation and only rare events with snowfall > 1 mm h-1 water equivalent (w.e.). Three of such intensive snowfall events occurred during 2011 contributing to anomalously large annual snow accumulation. This is the first deployment of a precipitation radar in Antarctica allowing to assess the contribution of the snowfall to the local surface mass balance. It is shown that on the one hand large accumulation events (>10 mm w.e. day-1) during the measurement period of 26 months were always associated with snowfall, but that on the other hand snowfall did not always lead to accumulation. In general, this promising set of robust instrumentation allows for improved insight in cloud and precipitation processes in Antarctica and can be easily deployed at other Antarctic stations.

Abstract: Abstract
The grounding line is a key element acting on the dynamics of coastal outlet glaciers.
Knowing its position accurately is fundamental for both modelling the glacier dynamics
and establishing a benchmark to which one can later refer in case of change. Here we
� �map the grounding line of the Astrolabe Glacier in East Antarctica (66 41 S; 140 05 E),
using hydrostatic and tidal methods. The first method is based on new surface and
ice thickness data from which the line of buoyant flotation is found. We compare this
hydrostatic map with kinematic GPS measurements of the tidal response of the ice
surface. By detecting the transitions where the ice starts to move vertically in response
to the tidal forcing we find control points for the grounding line position along GPS
profiles. With the help of a 2-dimensional elastic plate model, rigid elastic deviations are
computed and applied to these control points. Once the extent of the grounding zone,
the kinematic approach is consistent with the hydrostatic map. These two approaches
lead us to propose a grounding line for the Astrolabe Glacier that significantly deviates
from those obtained so far from satellite imagery.