Innovations Report: The shrinking expanse of Arctic sea ice is increasingly vulnerable to summer sunshine. Unusually sunny weather contributed to last summer’s record loss of Arctic ice, while similar weather conditions in past summers did not appear to have comparable impacts, new research concludes. The relative importance of solar radiation in the summer is changing," says Jennifer Kay of the National Center for Atmospheric Research (NCAR) in Boulder, Colo., who is lead author of the study. …