John AbrahamFri 3 Aug 2018 11.00 BST
Human carbon pollution is melting the Arctic, but aerosol pollution is slowing it down
The Arctic is one of the “canaries in the coal mine” for climate change. Long ago, scientists predicted it would warm quicker than other parts of the planet, and they were right. Currently, the Arctic is among the fastest-warming places on the planet. Part of the reason is that as the Arctic warms, ice melts and ocean water is uncovered. The ocean is darker than ice so it in turn absorbs more sunlight and increases its warming. This is a feedback loop.
Another reason is that the Arctic doesn’t get that much sunlight so increased energy from the atmosphere has a bigger influence there than it would have elsewhere.
Scientists have looked to the Arctic for clues and hints of human climate change over the past decades. The fact that the Arctic is warming has led to a 70% reduction in the volume of summer sea ice – an enormous loss of ice.
Decline in September Arctic ice extent (not volume). Illustration: Nasa