JERUSALEM, July 11 (Xinhua) — An international research group has found that extreme cold snaps in the United States are driven by disruptions in a high-altitude Arctic air mass called the polar vortex, Hebrew University of Jerusalem said Friday in a statement.
The study, published in Science Advances, reveals that when the vortex stretches over 16 km above Earth, it pushes freezing air into North America. Two distinct patterns were identified: one targets the U.S. Northwest and western Canada, while the other brings icy conditions to central and eastern states, according to the statement.
These events link to atmospheric wave shifts that bend the jet stream, dragging Arctic air southward. Since 2015, U.S. Northwest cold extremes increased due to a westward-shifting vortex pattern amplified by Pacific climate cycles.
The study underscores that climate change causes not just warming but also unpredictable severe weather, said the statement, adding that the study helps explain recent deadly freezes in Texas and the Central Plains. Enditem