Animation of the Earth showing the effects on the landmasses of a sea level rise of 70 metres. It has been calculated that the complete melting of the Greenland and Antarctica ice sheets would cause such a rise, with Greenland contributing some seven metres, and Antarctica more than 61m. Earth's sea level has fluctuated considerably even in the recent past: during the last glacial maximum some 20,000 years ago, so much water was stored as ice that sea levels were around 120 metres lower than today.