Reduction of storm activity due to climate change will increase extreme weather.
While summer storm activity has slowed over the past few years, the latest research shows that this decline could have a big effect on weather patterns in the U.S., leading to an increase in heat waves. The researchers from the Potsdam Institute for Climate Impact Research (PIK) found a marked reduction in average storm activity and the amount of turbulences known as synoptic eddies in the air, dropped around 10% since 1979. Heat events are expected to increase due to the reduction in summer air circulation – as the intensity of winds from the jet stream and other weather systems have lessened.
“The Weakening Summer Circulation in the Northern Hemisphere Mid-Latitudes," published in Science, points to rapid warming in the Arctic due to the burning of fossil fuels as the major driver of decreased circulation. As the polar region’s ice starts to melt, less sunlight is reflected from the sea surface than was reflected by the ice, leading to warmer waters in the ocean. This change results in a smaller temperature differential between the Northern hemisphere and the cold polar region, decreasing air motion and reducing storm activity.