Abstract

The UARS Microwave Limb Sounder (MLS) measures ClO (~25-45 km), O₃ (~15-80 km), H₂O (~15-85 km), and pressure (~30-60 km). ClO is the dominant form of chlorine which destroys ozone in the stratosphere; its measurement on a global scale, which will be done by the MLS, is essential for understanding and monitoring the depletion of stratospheric ozone by chlorine from industrial products. Simultaneous measurements of O₃ and H₂O provide additional important information on stratospheric ozone chemistry. The H₂O and O₃ measurements will be to higher altitudes than previously explored on a global basis. The pressure measurements provide the vertical reference for composition measurements. Secondary MLS measurement goals include H₂O₂, HNO₃, temperature, and one component of wind in the mesosphere. Measurements are made by observing millimeter-wavelength spectral line thermal emission as the instrument field-of- view is vertically scanned through the atmospheric limb. All are made simultaneously and continuously, at all times of day and night. Prior development for the UARS MLS included an aircraft [1,2] and balloon [3,4,5] MLS. Development has also started on an MLS experiment for the future Earth observing system (Eos); the Eos MLS is described in a separate paper presented at this meeting.

© 1990 Optical Society of America