Reporter Jonathan Watts from the Guardian joined an expedition studying the decline of Arctic sea ice and what this means for the planet:
Since the start of the satellite era in 1979, the summer Arctic has lost 40% of its extent and up to 70% of its volume. Other scientists calculate the rate of decline at 10,000 tonnes a second. Much of the multiyear ice is now gone. Most of what is left is the younger, thinner layer from the previous winter, which is easier for the sun to melt and the wind to push around. Wagner expects ice-free summers in 20 to 40 years, which would allow ships to cruise all the way to the north pole.
Ice-free summers are 10 times more likely if the world warms by 2C rather than 1.5C, according to the United Nations Intergovernmental Panel on Climate Change. The body of top international scientists said last year that the Arctic and coral reef systems were the ecosystems at greatest risk.
The demise of an entire ocean is almost too enormous to grasp, but as the expedition sails deeper into the Arctic, the colossal processes of breakdown are increasingly evident.
Image: Floating ice floes along one edge of Fram Strait. Photograph: Denis Sinyakov/Greenpeace as it appeared on the guardian.com on 7th June 2019.