Una missione di 16 settimane nell'Artico centrale

An undated handout picture provided on by the Alfred Wegener Institute of Polar and Marine Research on 06 October 2011 shows the research ship ‘Polarstern’ (North Star) sailing in the Arctic Ocean at the North?Pole. In the central Arctic the proportion of old, thick sea ice has declined significantly. Instead, the ice cover now largely consists of thin, one-year-old floes. This is one of the results that scientists of the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association brought back from the 26th Arctic expedition of the research vessel Polarstern. (Epa/Stefan Hendriks/Alfred Wegener Institute)