Heat-driven shifts in wind patterns could increase hurricane risks along US coastlines, researchers say


(NEW YORK) — Global warming isn’t just increasing the amount of moisture in the atmosphere — it’s also capable of shifting wind patterns, which will further increase hurricane risk in the U.S., according to new research.

Heat-driven shifts in large-scale atmospheric circulation could escalate the risk of hurricanes making landfall on the Gulf Coast and southern Atlantic coast in the U.S., a study published Friday in Science Advances found.

New model-based research found that enhanced surface ocean warming in the eastern tropical Pacific could trigger large-scale shifts in upper atmosphere wind patterns, according to the study.

These shifts could help steer hurricanes closer to the Gulf Coast and lower East Coast, decreasing the vertical wind shear in those regions, which could then allow hurricanes to intensify even more and amplify risks to coastal communities, the researchers said.

“The same winds that steer storms towards the U.S. coast will also make the storms stronger near the coast, because they are lowering wind shear,” Karthik Balaguru, a climate and data scientist at the Pacific Northwest National Laboratory and author of the study, told ABC News.

The model, called the Risk Analysis Framework for Tropical Cyclones and generated by the Pacific Northwest National Laboratory, is able to generate large ensembles of tropical cyclones and hurricanes, which then allows for robust quantification, Balaguru said. This is the first research to identify the mechanisms behind increased hurricane risk in the U.S. due to climate change, Balaguru said.

Scientists expect warming in the atmosphere and upper ocean to contribute to landfalling hurricanes becoming more destructive. Warming-induced shifts in large-scale wind patterns could also cause more storms to stall or dissipate more slowly on land.

The models found that the development of large-scale cyclonic wind patterns in the upper troposphere over the western Atlantic — due to heating in the eastern tropical Pacific — caused prevailing winds in the western Atlantic to shift westward.

That westward shift then steered hurricanes closer to the U.S. coast, increasing the frequency of landfalling hurricanes in a given year, the study found.

The new findings adds to existing research that climate change is creating stronger hurricanes that contain more moisture and as well as the U.S. Atlantic Coast becoming a “breeding ground” for rapidly intensifying hurricanes.

Future research on how global warming will affect changes in sea surface warming will be necessary to enhance the confidence of scientists to accurately predict hurricane risk in the future, Balaguru said.

Copyright © 2023, ABC Audio. All rights reserved.