Is Global Warming Behind The Record Snowfall Of Winter Storm Jonas?

Maybe.

Two days ago on RealClimate a post entitled "Blizzard Jonas and the Slowdown of the Gulf Stream System" suggests that there might be a link.  The argument is that rising ocean surface temperatures in the North Atlantic, especially somewhat south of Greenland, are tied to a slowing of the Gulf Stream.  These higher temperatures off the US East Coast then may be a clause of larger snowfalls in storms in the eaastern US, with a possible direct influence on this coming from warmer fresh water coming off Greenland  with glacier melt.  If this continues there could also be substantial impacts on northwestern Europe, although these may include cooling in some places.  This is tentative, but certainly something that should taken seriously and further studied.

Let me compare this with a possibly related phenomenon, which provides a warning that we must  proceed cautiously with this.  I am referring to the widespread reports about a decade ago claiming that global warming was increasing the frequency of hurricane in North America.  Quite a few public figures made a great big fuss over this, including Al Gore.  However, it turns out that the effect is a very complicated mixed bag, and if  anything it is the other way around, warming temperatures may lead to a lower frrequency  of Atlantic hurricanes?  How can this be?  One possibility is higher temperatures bring more sandstorms in western Africa that blow over the Atlantic, with this greater sand in the air inhibiting the formation of tropical depressions that lead to hurricanes.

While that may be the case, there is stronger evidence, although this remains a matter of  serious debate among climatologists, about the intensity of hurricanes that do occur, and such storms as Katrina and Sandy (which hit the New Jersey shoreline with flooding as Winter Storm Jonas has) being poster children for  this.  The argument on this is really straightforward: intensity of hurricanes does seem to be tied to higher late summer sea surface temperatures in the Atlantic and the Gulf of Mexico.  So, the case for more intense hurricanes to occur even as there may be fewer hurricanes overall is serious, if not  universally accepted by climatologists, and the mechanism would have similarities to the phenomenon now being posed as possibly increasing snowfall amounts in the eastern US due to  warmer ocean surface temperatures in the Atlantic.

Barkley Rosser