Melting ice in west Antarctica could raise seas by three metres, warns study

Nasa research finds ice in the region has gone into 'irreversible retreat' and claims effect is 'unstoppable'

A key area of ice in west Antarctica may already be unstable enough to cause global sea levels to rise by three metres of ocean rise, scientists said on Monday.

The study follows research published last year, led by Nasa glaciologist Eric Rignot, warning that ice in the Antarctic had gone into a state of irreversible retreat, that the melting was considered "unstoppable" and could raise sea level by 1.2 metres.