Stationary waves and the regional circulation response to global warming

Abstract:

The regional circulation response to global warming is strongly tied to the response of stationary eddies, which is largest during winter and summer in the Northern Hemisphere. We will discuss a theoretical framework, quasi-equilibrium dynamics, which connects local moist entropy gradients to the rotational and divergent flow associated with stationary waves. We will show, using idealized aquaplanet model simulations, that the framework can be used to understand the summertime stationary wave response to global warming, which is connected to the Monsoon-subtropical anticyclone circulation. Furthermore, the framework can be used to understand the circulation response to seasonal changes in insolation. Finally, we will discuss how the stationary wave response impacts transient eddies and the position of the extratropical jet stream.