Antarctica is classified as a desert, with what little precipitation there is coming down as snowfall. The ice sheet covering the continent gains mass predominantly via snowfall. The fact that there is very little surface melt means that ice cores provide a reliable history of precipitation in Antarctica over the years, and this snowfall record can be used to reconstruct regional climatic change and its causes through time. Across the continent, several deep ice cores have been drilled and hold information on hundreds of millennia of climate history. But the ice cores hold more information than just the quantity of snowfall – the presence of salt and certain proportions of different water isotopes contains information on the provenance of the water and the pathway it came to Antarctica by.
Using data from several major ice cores from East Antarctica, Claudio Scarchilli, Massimo Frezzotti and their colleagues investigated where the water that fell as snow over different parts of Antarctica originated in the last 20 years and how it got there. This knowledge is crucial for the correct interpretation of ice-core data as the time of year when the snowfall occurred and the origins and pathways of snow can bias results. By improving our understanding of ice-core records, the team have made an important contribution to the interpretation of regional climate change over both long and short timescales.
Ice2sea Work Package: WP2.4
Publication: Scarchilli, C., M. Frezzotti, and P. M. Ruti (2011), Snow Precipitation at four ice core sites in East Antarctica: provenance, seasonality and blocking factors, Climate Dynamics, 37, 2107-2125.