How Loss of Arctic Ice Amplified Superstorm Sandy

Cornell and Rutgers researchers report in the March issue of Oceanography that the severe loss of summertime Arctic sea ice - attributed to greenhouse warming - appears to enhance Northern Hemisphere jet stream meandering, intensify Arctic air mass invasions toward middle latitudes, and increase the frequency of atmospheric blocking events like the one that steered Hurricane Sandy west into the densely populated New York City area.

The lead author is Charles H. Greene, director of Cornell's Ocean Resources and Ecosystems program. Coauthor Jennifer A. Francis of Rutgers University's Institute of Marine and Coastal Sciences has written extensively on how arctic ice loss is driving extreme weather:

• Arctic Warming Favors Extreme, Prolonged Weather Events 'Such As Drought, Flooding, Cold Spells And Heat Waves'
• NOAA Bombshell: Warming-Driven Arctic Ice Loss Is Boosting Chance of Extreme U.S. Weather

The piece notes "there is increasing evidence that the loss of summertime Arctic sea ice due to green- house warming stacks the deck in favor of":

1. Larger amplitude meanders in the jet stream,
2. More frequent invasions of Arctic air masses into the middle latitudes, and
3. More frequent blocking events of the kind that steered Sandy to the west

So while this does appear to have been the perfect storm, we can, unfortunately, expect many more as we move toward ice-free arctic conditions in the coming years (see "Experts Warn 'Near Ice-Free Arctic In Summer' In A Decade If Volume Trends Continue").