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.
