Scientists expect the Arctic Ocean to lose its sea-ice cover in summer for the first time over the next two decades.

Temperatures at the North Pole recently soared more than 20°C above average, crossing the threshold for ice to melt.

The unusually mild temperatures were linked to a low-pressure system over Iceland directing warm air towards the North Pole.

The Arctic has warmed nearly four times faster than the global average since 1979.

A study found that Arctic summer sea ice would be lost even with drastic cuts to planet-heating pollution.