Larsen B ice shelf
The polar ice caps are already starting to melt on a worrying scale Nasa

If the past is anything to go by, sea levels could rise by at least 20ft as the impact of climate change is felt, scientists have claimed.

Research from the University of Florida shows that in the past when the Earth has been experiencing similar high temperatures, sea levels rose by up to 40ft.

The report, published in Science, says that sea levels jumped up by 20-30ft 125,000 years ago when there was a similar global average temperature as today's, whereas they rose 20-40ft 400,000 years ago when temperatures were around 2C warmer and atmospheric carbon dioxide levels peaked at around 280 parts per million – today the levels are much higher at around 400ppm and counting.

They discovered this by combining observations from geological records.

Additionally, they found that the North and South Poles warm faster in relative terms to the rest of the world, with lead author Andrea Dutton saying that "the polar ice sheets are out of equilibrium with the present climate," after noting that seas rose in response to melting ice sheets in Greenland and Antarctica.

Dutton explained: "As the planet warms, the poles warm even faster, raising important questions about how ice sheets in Greenland and Antarctica will respond. While this amount of sea-level rise will not happen overnight, it is sobering to realise how sensitive the polar ice sheets are to temperatures that we are on path to reach within decades."