Study links warming climate and Arctic cyclone frequency
By Summit Voice
FRISCO — A changing air pressure regime over the Arctic resulting from warmer temperatures may be driving an increase in extreme storms in the region. The hurricane-like cyclones that traverse the northern waters from Iceland to Alaska may foreshadow even more intense weather ahead, according to Dr. Stephen Vavrus, of the University of Wisconsin-Madison.
“This research shows that the Arctic appears to be expressing symptoms expected from ongoing climate change,” Vavrus said, explaining the findings of the study published in Geophysical Research Letters.
“The long-term decline in atmospheric pressure over most of the Arctic is consistent with the response typically simulated by climate models to greenhouse warming, and this study finds a general corresponding increase in the frequency of extreme Arctic cyclones since the middle 19th century,” he said.
The scientists used historical climate model simulations to demonstrate that there has been an Arctic-wide decrease in sea level pressure since the 1800′s.
Tracking changes in Arctic cyclone activity through time, Vavrus calculated a statistically significant, though minor, increase in extreme Arctic cyclone frequency over the study period, with increases strongest near the Aleutian Islands and Iceland. Dr. Vavrus suggests that, as of yet, the effect of climate change on Arctic cyclone activity has been minimal, but that future changes in polar climate will drive stronger shifts.
“One societally relevant implication is that more storminess probably means more erosion of Arctic coastlines, especially in tandem with declines in buffering sea ice cover and increases in thawing coastal permafrost,” Varnus said. “Erosion of Arctic coastlines has already been growing more severe during recent decades, and this study points to a contributing factor that will likely become an even more recognizable culprit in the future,” he concluded.