From the “weather is not climate unless it supports global warming department”, Dr. Roger Pielke Sr. responds to the claim elevated by Joe Romm (and now picked up by Time Magazine) that the east coast snowstorms are indicators of global warming. While you ponder that, click to watch the DC blizzard in progress via the US Senate live stream:
There is an article in Time magazine (h/t to Marc Morano for alerting us to it) by Bryan Walsh titled
The article correctly writes
“….it’s a mistake to use any one storm — or even a season’s worth of storms — to disprove climate change (or to prove it)…”
“Weather is what will happen next weekend; climate is what will happen over the next decades and centuries. And while our ability to predict the former has become reasonably reliable, scientists are still a long way from being able to make accurate projections about the future of the global climate.”
However, the article contains misinformation. I briefly comment on two issues presented in the article.
1. It is written
“The 2009 U.S. Climate Impacts Report found that large-scale cold-weather storm systems have gradually tracked to the north in the U.S. over the past 50 years.”
The current set of snowstorms in the Middle Atlantic states this winter actually have become intense further south than average. New England is certainly accustomed to these nor’easters. In an earlier post (see figure top), illustrates that the jet stream (as represented by the lower tropospheric temperature anomalies) was well south of its average position across the northern hemisphere. It is the polar jet stream which is where winter storms develop and intensify.
2. It is written
“As global temperatures have risen, the winter ice cover over the Great Lakes has shrunk, which has led to even more moisture in the atmosphere and more snow in the already hard-hit Great Lakes region, according to a 2003 study in the Journal of Climate.”
A new paper in EOS titled Severe Ice Cover on Great Lakes During Winter 2008–2009 [subscription needed]
“After a decade of little ice cover, from 1997–1998 to 2007–2008, the Great Lakes experienced extensive ice cover during the 2008–2009 winter. The area of Lake Superior covered by ice during the 2008–2009 winter reached 75,010 square kilometers on 2 March 2009, nearly twice the maximum average of nearly 40,000 square kilometers. By this time, Lake Superior was nearly completely ice covered, as were Lake Huron, Lake Erie, and Lake St. Clair, a small basin between Huron and Erie (Figure 1a). Even northern Lake Michigan experienced severe ice cover.”
These news articles would be more accurate (and effective) if the actual behavior of the climate system were presented.
For those interested, here is a typical winter pattern when we have an El Nino – Anthony
Luboš Motl also weighs in on the issue of linking these snows here