Evening Must-Read: Joe Romm: Warming Drives More Extreme Summer Heat Waves, Droughts And Deluges, Study Finds

Joe Romm: Arctic Warming Drives More Extreme Summer Heat Waves, Droughts And Deluges, Study Finds:

A new study links the past decade’s “exceptional number of unprecedented summer extreme weather events” in the U.S. and Europe with the “record declines in both summer Arctic sea ice and snow cover on high-latitude land.” Researchers at the Chinese Academy of Sciences, along with Rutgers Prof. Jennifer Francis, make the case in a Nature Climate Change study, “Extreme summer weather in northern mid-latitudes linked to a vanishing cryosphere”. Scientists predicted a decade ago that Arctic ice loss would shift storm tracks and bring on worse western droughts of the kind we are now seeing. Recent studies find that Arctic sea ice loss may well usher changes in the jet stream that lead to more U.S. extreme weather events…. Global warming melts highly reflective white ice and snow, which is replaced by the dark blue sea or dark land, both of which absorb far more sunlight and hence far more solar energy. That is one of the many sources of “polar amplification,” whereby the Arctic warms much faster than other parts of the globe. Now it seems increasingly clear that the amplified Arctic warming in turn amplifies extreme weather by shifting and weakening the jetstream…