The shocking extent of Arctic ice melt has been brought to light in a timelapse video that spans 32 years.
The NASA video, a graphic visualisation, was published on the space agency's website on Saturday and shows the ice sheets melting from 1984 to 2016.
"What we've seen over the years is that the older ice is disappearing," NASA sea ice researcher Walt Meier writes.
"This older, thicker ice is like the bulwark of sea ice ... but this older ice is becoming weaker because there's less of it and the remaining old ice is more broken up and thinner, so that bulwark is not as good as it used to be."
Mr Meier says a lot of older ice has been lost and that does not bode well for the future.
"We've lost most of the older ice: In the 1980s, multiyear ice made up 20 per cent of the sea ice cover. Now it's only about three per cent," Mr Meier said.
"The older ice was like the insurance policy of the Arctic sea ice pack: as we lose it, the likelihood for a largely ice-free summer in the Arctic increases."