Water

The Antarctic

The “Antarctic ice sheet” actually consists of two distinct ice-sheets. A Western one, which is smaller and is anchored to a group of islands, and an Eastern one, which is very vast and which, alone, accounts for 78% of the world’s glaciers,; the latter covers the Antarctic continent and rises with a number of domes, to heights over 4,000 m.  The two ice-sheets are separated by the Transantarctic mountain chain, which has peaks over 4,000 m high. The Western ice-sheet has a maximum thickness of 3.5 km, and its base is  prevalently below sea level, while the Eastern ice-sheet reaches thicknesses up to 4.5 km and it is prevalently above sea level. Antarctic ice forms slowly due to the scarce precipitations, however it melts equally slowly due to the very low temperatures : it is here that we can find the most ancient ice on Earth. It is still not possible to make any forecasts about the state of health of the Antarctic ice-sheet : its balance still seems positive, even though the Western part has incurred large losses due to calving as its base is below sea level. The Ross Ice Shelf, which is the most extensive in the planet, is named after James Ross, who was navigating on account the British government to reach the South Pole, and discovered it in 1841: the enormous walls bordering this ice shelf brought an end to the Captain’s explorations, Ross did not reach the South Pole, but wrote a detailed report on the margins of the ice shelf, leaving extremely precious historical information for the study of the evolution of Antarctic ice.