Global warming has led to more ice in the sea around Antarctica and could help insulate the southern hemisphere from atmospheric warming.
A Dutch study says that unlike in the Arctic region, sea ice around Antarctica has expanded at a significant rate since 1985.
Published online in Nature Geoscience, the article suggests cool freshwater from melt beneath the Antarctic ice shelves has insulated offshore sea ice from the warming ocean beneath.
Richard Bintanja of the Royal Netherlands Meteorological Institute and colleagues say the Antarctic sea ice expands during southern hemisphere autumn and winter in response to this fresh, cool surface layer that freezes easily.
''Against the background of global climate warming, the expansion of Antarctic sea ice is an exceptional feature, which seems to be associated with decreasing sea-surface temperatures in the Southern Ocean,'' they write.