Sea-level rise from Antarctic ice melt may not be as bad as feared

Antarctica’s ice sheets are “extremely unlikely” to collapse enough to cause more than a 30cm rise in global sea levels by the end of this century, according to new research from the Open University.

As the world warms, the vast, kilometres-thick ice sheet is expected to grow unstable, causing large parts of it to slide into the ocean. Earlier models said that in the worst-case scenario, the sheet’s collapse could cause as much as 50cm or even a metre of sea level rise worldwide; one study, last year, suggested a catastrophic collapse of the sheet could cause a sudden 4m rise. That is before taking into account the sea level rise from other sources, such as the melting of the Greenland ice cap, or “thermal expansion”.

However, the new study – which its authors say is the most robust and precise to date – says that the upper limit is much lower, almost certainly no more than 30cm by the year 2100.