On the polar vortex streamer dynamics

Potential vorticity (PV) streamers and cutoffs are indicators to the Rossby wave breaking (RWB) near the extratropical tropopause. In the Rossby waves breaking, the formation of elongated high-PV stratospheric air tongues extending to the equator and tropospheric low PV air tongues extending to the pole are obtained. There are two types of wave breaking, which are referred to as equatorward and poleward types of the RWB. Frequently, the PV tongues are stretched into narrow filaments, the so-called PV streamers that split to PV cutoff vortices. Here stratospheric PV streamer and cutoff are stratospheric features on isentropic surfaces. In this paper, the configuration of a potential vortex field for model data is investigated. The main areas of the RWB for the winter and summer periods are shown.