Physics Colloquium, 'Fast jet stream winds get faster under climate change'

Presented by: Tiffany Shaw, University of Chicago

Date: April 5, 2023

Host: Michael Ritzwoller

Abstract: Earth's upper-level jet streams influence the speed and direction of travel of weather systems and commercial aircraft. The fastest jet stream winds are also linked to severe weather occurrence. Climate change is known to accelerate the average speed of the jet stream. However, little is known about how the fastest jet stream winds will change. Here we show fast jet stream winds get faster under climate change using daily data from climate model projections across a hierarchy of physical complexity. The fastest winds also increase substantially more than the average winds. We give a physical basis for why fast winds get faster and show it follows from the moist get moister response under climate change. The results show moist thermodynamics can explain projected future changes in commercial flight times and clear-air turbulence, including a potential increase in severe weather occurrence under climate change.