An expected slowdown of large-scale heat circulation in the Atlantic Ocean could temporarily halt the decline of Arctic sea ice (pictured).

Credit: Ragnar Th. Sigurdsson/Arctic Images/Alamy

Stephen Yeager at the National Center for Atmospheric Research in Boulder, Colorado, and his colleagues used an Earth-system model to analyse the causes of decadal trends in sea-ice extent in the North Atlantic. They found that the drastic retreat of sea ice since 1990 coincided with a strong Atlantic circulation that brought warm surface water from the tropics to high latitudes. If this circulation were to weaken, as observations suggest that it will, less heat arriving in the Arctic Ocean will probably lead to a pause in winter sea-ice loss over the next 5 to 10 years, the authors conclude.

They add, however, that the rate of sea-ice melting could jump back up afterwards as global warming continues.

Geophys. Res. Lett. (2015)