What are ice shelves?
Ice shelves are the floating edges of ice sheets that cover Greenland and Antarctica. These ice sheets contain 77 per cent of the world’s freshwater, 99 per cent of all glacial ice and cover more than 10 per cent of the Earth’s land area. If the ice sheets were to melt entirely, sea level would rise by nearly 80 metres. Ice sheets form from the accumulation of snow on the continents. Some snow survives summer melting and evapouration to eventually become compacted under further snowfall. The ice formed by this process spreads out over the land, transported by glaciers and ice streams. Where ice streams reach the edge of the continent, they feed floating ice shelves or glacier tongues that spread out further over the sea. Ice shelves cover more than 40 per cent of the continental shelf around Antarctica. Ice shelves have sea water cavities beneath them that open to the ocean at their edges. These cavities may be several hundred kilometres long, with water several hundred metres deep und
