AUSTIN (KXAN) — A new study, conducted in part at Texas State University, found that rapid warming in the Arctic may contribute to heat waves right here in the United States.
The study highlights a statistical relationship between Arctic sea ice and extreme weather in the U.S. The research suggests that during warmer years in the Arctic when sea ice extent is low, heat waves are more frequent to the south across much of the eastern half of the U.S. The authors found that this is due to North Atlantic ocean-atmosphere interactions involving jet stream currents in the Northern Hemisphere.
The evidence suggests that these factors allow specific weather patterns, including heatwaves, to persist for longer periods than they have in the past. This research is in line with other recent climate change studies that have found global weather patterns to be more “stagnant” than historical averages. July was on track to be the hottest recorded month in history for global temperatures, according to a report by NBC News.
Storm systems marching around the globe ride high-altitude currents of air called the jet stream. The jet stream relies upon a large temperature gradient between the warm tropics and the cold poles, producing something called thermal wind.
“With the Arctic warming faster than in the mid-latitudes, you would expect that the temperature and pressure gradient, and therefore Northern Hemisphere atmospheric circulation, to be affected as a physical response,” Ballinger said. “We’re seeing evidence of this through more persistent weather systems in the mid-latitudes.”
Continued warming in the Arctic could also cause a greater increase in severe weather throughout the Northern Hemisphere.
“A similar incident has played out this year as low Hudson Bay and Baffin Bay spring/summer ice coverage, coupled with above-normal and persistent high pressure over Greenland, appears to be slowing down the west-to-east path of jet stream and diverting it to the south, contributing to the recent Midwest heatwave,” Ballinger said.
In addition to heatwaves, the researcher suggests Arctic conditions contribute to ongoing dry or rainy weather patterns and harsh winter weather in the U.S. and Siberia. Understanding these connections could help scientists improve their weather and climate projections in different parts of the world.