Monday 30 Oct 2017: Dynamics-radiation interactions in the tropical tropopause layer
Prof. Peter Haynes - University of Cambridge
The tropical tropopause layer (TTL) (14-18.5km, 150-70hPa) is characterized by cold temperatures and (above ~16km) large-scale upwelling. The time variation of these on annual and interannual timescales has important implications for stratospheric chemical species, particularly water vapour. Dynamical forcing by waves and variation of radiatively active species (ozone and water vapour) are both potentially important in determining the characteristics of the TTL and its time variation. This talk will use (relatively) simple models of the TTL system to explain the observed latitudinal variation of upwelling (with an equatorial minimum and off equatorial maxima) and to examine the roles of dynamical processes and radiative effects in driving the annual cycle in temperatures and upwelling.