ScienceNews: This spring, a larger fraction of sea ice in the Arctic is much thinner than average, a sign that the ice may be more likely to melt this summer. Light orange areas are covered by brand-new, first-year ice, which typically is less than two meters thick. Darker orange and red areas are covered by multiyear ice, which usually measures three meters or more thick. The spring melting of the Arctic Ocean’s ice cap has already begun, and data suggest that the ice is more vulnerable than …