Stratospheric thermal damping times

Abstract

Radiative damping of stratospheric temperature waves has wide implications for stratospheric physical processes. Damping is linearly parameterized as proportional to the local temperature. Thermal damping is calculated using the Goddard radiative transfer model and 17 years observations. Damping times of stratospheric temperatures are calculated for each month at all latitudes. These damping times are consistent with previous stratospheric estimates, but show shorter tropical time scales. Damping times range from an annual global average of 28 days (100 hPa) to 4 days (1 hPa). A considerable annual cycle is seen over much of the stratosphere, which is directly related to the annual cycle of temperatures, with longer damping times associated with colder temperatures.