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During the XVI Italian Antarctic Expedition (2000-2001) the geomorphologic survey of permafrost-related polygons has been carried out in the northern sector of Mesa Range - Pain Mesa - located in the upper part of Rennick Glacier. An ice wedge was found in a volcanic regolith at an elevation of about 2200 m a.s.l.. This altitude is below the trimline that in this sector of Mesa Range is at 2380 m a.s.l.. Samples of ice were taken using a 14 mm internal diameter ice screw that was inserted into the ice wedge in vertical sequences. A co-isotopic study was performed, measuring both oxygen (?18O) and hydrogen (?D) isotope compositions. Tritium activity measurements were carried out on the same samples as well as chemical determinations of both major cations and anions. The ?18O and ?D obtained showed a strong divergence from the expected snowfalls occurring at this elevation, with extremely negative d excess values. Melting-refreezing and/or sublimation processes were taken into account to define the origin of the ice forming the wedge. The tritium data obtained suggest that the growth process of the ice wedge might be active still today. High values of non-sea salt sulphate concentrations, obtained for all samples, showed a strong contribution from a terrestrial source for sulphate which is probably associated with calcium.

A detailed study of organic carbon content obtained from two sediment cores collected in the Joides basin, western Ross Sea, Antarctica, was carried out. The variations observed during the last deglaciation and the Holocene were compared to the high-resolution climatic records (EPICA DC and Taylor Dome) preserved in the ice. The importance of the carbon content as a proxy for palaeoclimatic and palaeoenvironmental changes was investigated. A dramatic decrease in the Ross Sea palaeoproductivity was observed during the Antarctic Cold Reversal (12.5–14 kyr BP). Another decrease in total organic carbon in the second half of the Holocene (after 5–6 kyr BP) confirms the climate worsening observed in previous studies.

In the framework of the International Trans-Antarctic Scientific Expedition (ITASE) programme, France and Italy carried out a traverse along one west–east and two north–south transects in East Antarctica from November 2001 to January 2002. Eighteen shallow snow–firn cores were drilled, and surface snow samples were collected every 5km along the traverse. Firn temperatures were measured in boreholes down to 30 m. The cores were analyzed for β radioactivity to obtain snow accumulation-rate data. The surface snow samples were analyzed for δ18O to correlate isotopic values with borehole temperatures. Multiple regression analysis shows a global near-dry-adiabatic lapse rate and a latitudinal lapse rate of 1.05˚C(˚ lat. S)–1, in the Dome C drainage area. Analysis of firn temperatures reveals a super-adiabatic lapse rate along the ice divide between Talos Dome and the Southern Ocean coast, and in some sectors along the ice divide between the Astrolabe Basin and D59. Snow accumulation rates and firn temperatures show warmer temperatures and higher accumulation values close to the ice divides extending from Talos Dome and Dome C to the Southern Ocean. The spatial pattern of data is linked with a katabatic-wind-source basin and moisture-source region.

High-resolution crystallographic, salinity and isotopic analyses of a 45 m ice core reveal the presence of a thick layer of marine ice near the grounding line of the Nansen Ice Shelf, Antarctica. The anomalous formation of marine ice in a zone assumed to be the site of active basal melting leads us to propose the hypothesis of large basal crevasses as a favorable environment for important marine-ice accretion. This hitherto unexplored possibility is supported by the overall field configuration and by the discrepancy in some ice properties between this core and the marine-ice sections of previous drilling projects. These findings could have important implications for the general stability of ice shelves and their disintegration processes. The specific properties of this core reveal that marine ice is post-genetically deformed.