L Ruby Leung News Today

New research finds that a record Arctic sea ice melt season in 2007 initiated a “regime shift” to thinner, more transient ice that may be “irreversible”; another study shows that atmospheric rivers from the south are warming the Arctic in winter.

A team led by Penn State scientists found powerful storms called atmospheric rivers are increasingly reaching the Arctic in winter, slowing sea ice recovery and accounting for a third of all winter sea ice decline.