Antarctica: Wind as engine of climate in sea-ice formation


Antarctic sea ice or ice pack is an important component of the climate system and its seasonal cycle affects global climate dynamics -because of its interplay with the planetary albedo- atmospheric and oceanic circulation, in addition to being an essential component of the polar marine ecosystem.

The research, published on the magazine Nature Communications, has explained for the first time the environmental processes which have affected sea ice variability and the abundance of penguins and seals in the Sea Ross in Antarctica in the last 10thousand years.

The study was conducted by italian researchers of the National Research programme in Antarctica (conducted by ENEA for the logistics and the CNR for planning and scientific coordination, in collaboration with the french COLLEAGUES as part of the international projects HOLOCLIP ( and TALDICE ( and a Phd in collaboration with the Universities of Trieste and Siena by Karen Mezgec.

Aerial photography of Terra Nova Bay (Ross Sea, Antarctica) during a katabatic wind event with neoformation of sea ice (Photo by Frezzotti M. ENEA-PNRA)
Aerial photography of Terra Nova Bay (Ross Sea, Antarctica) during a katabatic wind event with neoformation of sea ice (Photo by Frezzotti M. ENEA-PNRA)
“Our study- MassimoFrezzotti, ENEA researcher, explained- has shown how winds blowing in Antarctica have a fundamental role, similar if not superior to that of temperatures and rains, in driving climate and conditioning polar ecosystems. Climate systems should be able of recreating the strenght and persistence of winds in the past millennia in order to simulate climate changes in Antarctica induced by fossil fuels”.

“Variations in the extent of sea ice in the past can be derived by climate indicators or “proxy”, present in natural polar archives, Barbara Stenni, paleoclimatologist and professor at the Cà Foscari University in Venice, explained. They can be found both in ice cores and in water-sediments collected in the Ross Sea area”.

“The variability in the extension and persistence of sea ice has affected in the course of time, the evolution of coastal areas and the accessibility to beaches, providing seals and Adelia penguins with the opportunity to colonize Ross Sea coasts, even modifying their diets, as shown by the discovery of many abandoned colonies conserving the stratification of several phases of occupation”, Carlo Baroni and Maria Cristina Salvatore (professors at The Earth Science Department of the University of Pisa and associated researchers at the CNR-IGG in Pisa), explained.

For the first time a link has been established among atmospherical data, ice cores and sediment cores. Thanks to diatomes, silica algae dominant in the cold antarctic seas, it has been understood that the marine environment, from the columnal ice to the sediments, has answered to variations in the ice extent and ultimately to climate variations in the last 10thousand years. The presence-absence of some characteristic species has highlighted the great climate variability of this time window so close to our present world” Ester Colizza, sedimentologist, and Romana Melis, micropaleontologist at the Department of Mathematics and Geosciences at the University of Trieste, said.