Simon Wang, a professor of climate dynamics at Utah State University, said scientific interest in the jet stream has intensified in the past few years but exactly how it influences extreme weather remains “inconclusive.”
There are actually many jet streams, fast-flowing air currents found at various levels of the atmosphere that march west to east, redistributing energy around Earth in the form of cold and heat. The wavy amplitude of the airflow is partly influenced by temperature differentials that move the air currents from north to south, then south to north and so on. Extreme weather occurs when the waves get stuck in bottlenecks and stall.
Wang said the jet stream’s historical patterns are changing in part because the Arctic is warming faster than the tropics. Wang said the big question remains how much those changes are driving the extreme weather shifts. The scientific debate is especially fierce when it comes to winter in the northern hemisphere and the factors that influence the jet stream, including when mountains interrupt airflow, the comparatively larger proportion of land to water, and even pollution.
“I really prefer to say that the jet stream does not cause global warming,” Wang said. “It is responding to global warming or global cooling.” In the end, interactions from redistributed energy lead to extreme weather.