Global distributions of temperature, carbon dioxide, ozone, and non-LTE parameters in mesosphere and lower thermosphere (CRISTA-1 experiment)

摘要

High-altitude limb infrared radiance spectra (CO_2 15μm and O_3 9.6 μm bands) registered during CRISTA-1 experiment in November 1994 were interpreted using multiparameter inversion algorithm accounting for the nonlocal thermodynamic equilibrium conditions (non-LTE). Global distributions of temperature in the altitude range 40-120 km were obtained simultaneously with the distributions of CO_2 and O_3 (40-90 km) and vibrational temperatures of the lower vibrational states of CO_2 and O_3 molecules. Mean zonal values of temperature agree with CIRA-86 and SMLTM models. The root mean square variability of temperature reaches its maximum of 45 K at 105 km. Mesospheric temperature inversions were detected in 85% of cases during observations. The retrieved CO_2 profiles demonstrate that the altitude level, up to which CO_2 is well mixed, is considerably lower (70-75km) than predicted by models (85-90 km). Maximal diurnal variations of ozone were observed at 90 km altitude, where the mean value of volume mixing ratio is close to 2 ppmv for daytime and 7 ppmv for nighttime. The altitude levels of the LTE breakdown for the vibrational states of CO_2 and O_3 molecules and also the magnitude and vertical behavior of the non-LTE effect are in good agreement with numerical models.