IMPLICATIONS OF SATELLITE OH OBSERVATIONS FOR MIDDLE ATMOSPHERIC H2O AND OZONE

Satellite observations by the Middle Atmosphere High Resolution Spectr ograph Investigation (MAHRSI) have produced global measurements of hyd roxyl (OH) in the atmosphere. These observations reveal a sharp peak i n OH density near an altitude of 65 to 70 km and are thus consistent w ith observations from the Halogen Occultation Experiment (HALOE) on th e NASA Upper Atmosphere Research Satellite (UARS), which showed an une xplained H2O layer at the same level. Analysis of stratopause (about 5 0 kilometers) OH measurements and coincident ozone observations from t he Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere (CRISTA) experiment reveals that the catalytic loss of ozone attributa ble to odd-hydrogen chemistry is less than that predicted with standar d chemistry. Thus, the dominant portion of the ozone deficit problem i n standard models is a consequence of overestimation of the OH density in the upper stratosphere and lower mesosphere.