This summer's record-breaking ice melt in the Arctic is part of a worrying trend, scientists are warning.
Researchers say the sea ice is getting thinner and melting at "amazing" speed.
Last month, sea ice levels dropped to their lowest since satellites began watching the region more than 30 years ago.
Dr Kim Holmen from the Norwegian Polar Institute said: "It is a greater change than we could even imagine 20 years ago, even 10 years ago."
He added that scientists would have to change the way that they work and how they understand the area.
Another scientist, Dr Edmond Hansen, said: "It is truly amazing - it is a huge dramatic change in the system.
"This is not some short-lived phenomenon - this is an ongoing trend.
"You lose more and more ice and it is accelerating - you can just look at the graphs, the observations, and you can see what's happening."