Statistics of mesospheric coolings during stratosperic warmings in observations and simulations

Sudden stratospheric warmings are frequently associated with mesospheric coolings which indicate the vertical extension of these events. In order to find their statistical characteristics we diagnosed a combined dataset from Aura-MLS satellites and ERA-Interim reanalyses. The observations indicate, that mesospheric coolings occour with about 20 % during stratospheric warmings. In an analysis of model simulations with KMCM, HAMMONIA and WACCM we found similar occurence frequencies. Additionally, there is a weak relation of the mesosperic coolings to the duration and intensity of the stratospheric warmings and the split form of the polar vortex. Dynamical aspects of these relations with regard to planetary and gravity waves are discussed.