Abstracted/indexed

This paper investigates the waveguidability of midlatitude jets, i.e., their ability to duct Rossby waves in the zonal direction. Waveguidability is quantified in the framework of an idealized numerical model and compared with the predictions from two complementary theoretical concepts. It is found that the concept of ray tracing, which has been used extensively in the past, does not provide a satisfactory explanation for the numerical results. Further analysis uncovers the underlying reasons.

Sudden stratospheric warmings (SSWs) are extreme events that influence surface weather up to 2 months after onset. We remove wave–wave interactions (WWIs) in vertical sections of a general circulation model to investigate the role of WWIs in SSW formation. We show that the effects of WWIs depend strongly on the pressure levels where they occur and the zonal structure of the wave forcing in the troposphere. Our results highlight the importance of upper-level processes in stratospheric dynamics.