Aura Microwave Limb Sounder (MLS) Early Validation Results

The Earth Observing System (EOS) Microwave Limb Sounder (MLS) instrument aboard the Aura satellite, launched in July 2004, makes thermal emission measurements of many atmospheric species as well as temperature. Early validation results are presented here for some of the MLS measurements: temperature, ozone (O3), water vapor (H2O), hydrogen chloride (HCl), nitrous oxide (N2O), nitric acid (HNO3), and carbon monoxide (CO). The MLS Version 1.5 data retrievals are discussed, with a focus on the January-March 2005 time period. Global comparisons are made, mostly for stratospheric profiles, using long-standing global satellite and meteorological datasets, as well as some measurements from more recently-launched satellites. Comparisons of MLS data with measurements from the Ft. Sumner, New Mexico, September 2004 balloon flights are also presented. Overall good agreement is obtained, often within 5 to 10%, but we point out certain issues and larger systematic differences.