Aug 11, 2010

Russia Fires, Pakistan Floods Linked? Extreme weather driven partly by global warming, experts say.

Moscow
Russia
by
Christine Dell'Amore
,
National Geographic
A family leaves flooded Baseera, Pakistan, this week. Photo: Adrees Latif, Reuters
A family leaves flooded Baseera, Pakistan, this week. Photo: Adrees Latif, Reuters

[The] monsoon—a seasonal wind system that brings rain and floods to Pakistan and much of the rest of Asia in summer—also drives the circulation of air as far away as Europe, said Kevin Trenberth, a senior scientist at the Boulder, Colorado-based National Center for Atmospheric Research. Air pumped into the upper atmosphere by monsoon winds has to come down somewhere. And with the monsoon's giant reach, much of that air seems to be settling over Russia, where it's creating high-pressure conditions, which favor heat waves, Trenberth said. Near high-pressure systems, air tends to sink, which discourages clouds from forming. Such circulation patterns are normal, but they're also being enhanced by rising sea temperatures due in part to global warming, he added.