The Zonally Averaged Circulation of the Middle Atmosphere.
Abstract
The steady state, zonally averaged circulation of the middle atmosphere (15-125 km) is studied with a quasigeostrophic, numerical model that explicitly includes a self-consistent calculation of solar radiative heating due to oxygen and ozone absorption, Newtonian cooling, Rayleigh friction, tropopause boundary conditions based on climatological averages, and the effects of vertically propagating planetary waves. We find the direct, radiatively driven pole to pole circulation at solstice is sufficient to account for the cold summer mesopause and warm isothermal winter mesosphere with associated zonal jets of realistic magnitude. The climatological heat and momentum fluxes associated with planetary wave number 2 have a negligible effect on the mean circulation. With planetary wave number 1 no steady state solution could be obtained due to the formation of easterlies and hence critical layers in the winter mesosphere. We also find that the radiative heating associated with secondary peaks in the ozone density at the mesopause could render the polar mesopause region convectively unstable.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1977
- Accession Number
- ADA047810
Entities
People
- D. Strobel
- M. Schoeberl
Organizations
- United States Naval Research Laboratory