Ice wastage on the Kerguelen Islands (49°S, 69°E) between 1963 and 2006

Etienne Berthier (1) , Raymond Le Bris (2) , Laure Mabileau (1) , L. Testut (1) , Frédérique Rémy (1)

1 LEGOS - Laboratoire d'études en Géophysique et océanographie spatiales
2 Department of Geography [Zürich]

We observed the wastage of ice masses on the Kerguelen Islands (Indian Ocean, 49°S, 69°E) using historical information and recent satellite data. Overall, the total ice-covered area on the islands declined from 703 to 552 km2 between 1963 and 2001, a reduction of 21%. The area of Cook ice cap (the main ice body) decreased asymmetrically from 501 to 403 km2. West-flowing glaciers lost 11% of their area while east-flowing glaciers lost 28%. After 1991, the retreat rate accelerated from 1.9 km2/yr (1963-1991) to 3.8 km2/yr (1991-2003). Between 1963 and 2000, the ice volume loss was 25-30 km3, equivalent to an area-average ice thinning rate of 1.4-1.7 m/yr. The glacial retreat took place in the climatic context of a relatively low level of precipitation (compared to the 1950s) and a ~1°C warming that occurred between 1964 and 1982. The acceleration of the ice losses since, at least, the 1990s indicates that the state of the ice bodies on the Kerguelen Islands is still far from balanced. Together with other studies in Patagonia, South Georgia and Heard Island, our analysis is consistent with a pattern of strong and accelerated wastage of ice masses influenced by the Southern Ocean.

Domaines: Glaciologie

Etienne Berthier, Raymond Le Bris, Laure Mabileau, L. Testut, Frédérique Rémy. Ice wastage on the Kerguelen Islands (49°S, 69°E) between 1963 and 2006. Journal of Geophysical Research, 2009, 114, pp.F03005. ⟨10.1029/2008JF001192⟩. ⟨hal-00406745⟩