ATMOS ATLAS-3 INFRARED PROFILE MEASUREMENTS OF TRACE GASES IN THE NOVEMBER 1994 TROPICAL AND SUBTROPICAL UPPER TROPOSPHERE/

Vertical mixing ratio profiles of four relatively long-lives gases, HC N, C2H2, CO, and C2H6, have been retrieved from 0.01 cm(-1) resolution infrared solar occultation spectra recorded between latitudes of 5.3 degrees N and 31.4 degrees N. The observations were obtained by the At mospheric Trace Molecule Spectroscopy (ATMOS) Fourier transform spectr ometer during the Atmospheric Laboratory for Applications and Science (ATLAS) 3 shuttle flight, 3-12 November 1994. Elevated mixing ratios b elow the tropopause were measured for these gases during several of th e occultations. The positive correlations obtained between the simulta neously measured mixing ratios suggest that the enhancements are likel y the result of surface emissions, most likely biomass burning and/or urban industrial activities, followed by common injection via deep con vective transport of the gases to the upper troposphere. The elevated levels of HCN may account for at least part of the ''missing NOy'' in the upper troposphere. Comparisons of the observations with values mea sured during a recent aircraft campaign are presented. Published by El sevier Science Ltd.