Greenland The result is easy to see. Thanks to that meltwater and to the even bigger impact from warming seawater getting underneath glacier snouts, the Greenland ice is rushing towards the sea, calving monster icebergs. The 3-kilometer-wide Jakobshavn glacier is the greatest of Greenland’s ten ice streams. In 1992, the glacier was moving at a steady 5.6 kilometres a year; by 2003, it was roaring along at 12.5 kilometres a year. All that ice could raise sea levels three feet by the end of the century.