Antarctic glacier nears its tipping point

A major Antarctic glacier is close to a tipping point that would accelerate the rate at which it melts and push up the global sea level significantly in the coming decades, a new study warns.

The Thwaites glacier in the Amundsen Sea has lost about 600 billion tonnes of ice since the 1980s as parts of it break off the edge.

But the melting process could speed up considerably in the coming years as the glacier approaches a tipping point that could lead it to be wiped out entirely within 150 years.

Losing the whole glacier would increase the world’s sea level by about 50 centimetres – considerably more than the 20 centimetre increase that has occurred so far as a result of the ocean warming caused by climate change.

This would put large numbers of the world’s cities under water – while the simultaneous melting of other major Antarctic glaciers would push sea levels up much higher still, the research finds. Large Antarctic glaciers typically begin on land and extend into the sea.

The tipping point occurs as the land and sea parts of the glacier become detached, accelerating the flow of ice from the land into the sea.

Theglacierisamongfivethat have doubled their rate of ice loss in the last six years.

The prediction came after 500 ice-flow models of the glacier all predicted the instability would be triggered if the rate of ice melt due to warming oceans stayed at today’s levels.