Knowledge Bank

The Microwave Limb $Sounder1$ is currently measuring atmospheric thermal emission spectra of $O3$ and ClO from orbit aboard the Upper Atmospheric Research Satellite. Among the parameters necessary for retrievals of accurate atmospheric distributions of these species are the air broadened linewidths of the transitions being observed. The $N2$ and $O2$ broadened linewidths of the two $O3$ transitions near 184 and $206GHz2$ and the ClO transitions at 204 GHz have been measured in the 200-300K temperature range. The air broadened linewidths derived from these measurements are accurate to 3%. The laboratory results will be shown as well as their relationship to recent satellite measurements of upper atmospheric $O3$ and ClO.