Saturday, June 8, 2013

What Happens in the Arctic Unfortunately Is Not Staying in the Arctic

Chuck Clusen, Director, National Parks and Alaska Projects, Washington, DC

What Happens in the Arctic Unfortunately Is Not Staying in the Arctic:

The Arctic Ice Pack May Be as Important to Us People as to the Polar Bears. Its Melting Must Be Brought Under Control. Oil and Gas Activities Contribute to Arctic Amplification by Spewing Black Carbon (soot) and Releasing Methane As Well Add to the Oil We Burn.


Polar bears swim for long distances between melting blocks of park ice.

It is widely known the Arctic is warming more rapidly than any other place on Earth-more than twice as fast. This is occurring due in significant part to what is called "Arctic amplification." This is when solar radiation is absorbed to a greater degree by melted open water, or land that has prematurely lost its seasonal snow cover, than the solar absorption rate of ice and snow. As the Arctic warms, the temperature differential between the Arctic climate zone and the temperate climate zone decreases. This effect has a tendency to push the jet stream north. Yet, Arctic warming is not uniform geographically or temporally, resulting in Arctic cold fronts moving south. These cold fronts can push the jet stream back south, but not necessarily uniformly, creating a north-south wave in the jet stream.

As reported in the March 2013 edition of Oceanography: The Offical Magazine of the Oceanography Society, in an article written by Professor Jennifer A. Frances of Rutgers University; Charles H. Greene, a program director at Cornell University; and Bruce C. Monger, a senior research associate at Cornell University, the warming of the Arctic may have had a lot to do with the trajectory of Superstorm Sandy.

While Sandy started out as a relatively normal late-season hurricane, it markedly changed as it moved north. An extra-tropical cyclone merged with Sandy due to a cold front from the Arctic moving down the Mississippi Valley, pushing a southerly wave in the jet stream. Simultaneously, the ocean waters under Sandy stayed unusually warm for that time of year and, most importantly, a strong high-pressure blocking pattern over Greenland tucked into the jet stream loop going back north. This high-pressure system prevented Sandy from steering northeast and out to sea as October hurricanes normally track. With no way for Sandy to go north or east, it made a very sharp turn west, hitting the densest populated portion of the eastern seacoast.

In recorded weather history there is no prior record of such storm behavior. As Sandy moved west it combined with the other extra-tropical cyclone which had turned into an early winter nor'easter. The new combined storm became huge and ferocious. The storm exhibited record-low atmospheric pressure and the unusual strong high-pressure block to the north created a huge area of violent east winds that pushed water up onto the eastern coastline, from New Jersey to Nova Scotia. We all know the devestation Superstorm Sandy left in its wake.

Superstorm Sandy damage.jpg

Storm damage from Superstorm Sandy.

Scientists believe that the movement of the jet stream north, the larger amplitude meanders of the jet stream, the more frequent Arctic cold mass invasions into the middle latitudes, and the more frequent blocking events that forced Sandy west rather than follow the traditional storm tracks northeast, are all new phenomenon. If these events become common, anyone who lives in the temperate zone may have to contend with more devastating storms like Sandy..

Oceanography March 2013 image.bmp

Much of the material for this blog was taken from an article published in Oceanography: Green, C.H., J.A. Francis, B.C. Monger. 2013 Superstorm Sandy: A series of unfortunate events? Oceanography 26(1):8-9, http:dx.doi.orgt/10.5670/oceanog.2013.11. Also, an analysis by Jennifer Francis, "Linking Weird Weather to Rapid Warming of the Arctic", posted on 05 March 2012 in Business & Innovation Climate Science & Technology Sustainability Water Antarctica and the Arctic Asia North America was used.

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