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A simple, classical, and expedient method for the retrieval of atmospheric pressure-temperature profiles has been applied to the high-resolution infrared solar absorption spectra obtained with the atmospheric trace molecule spectroscopy (ATMOS) instrument. The basis for this method is a rotational analysis of retrieved apparent abundances from CO2 rovibrational absorption lines, employing existing constituent concentration retrieval software used in the analysis of data returned by ATMOS. Pressure-temperature profiles derived from spectra acquired during the ATLAS 1 space shuttle mission of March-April 1992 are quantitatively evaluated and compared with climatological and meteorological data as a means of assessing the validity of this approach.

The Atmospheric Trace Molecule Spectroscopy (ATMOS) instrument recorded 19 sets of interferograms during solar occultations in both the Northern and Southern Hemispheres over the course of the Spacelab 3 mission. The resulting IR spectra furnish concentration profiles for over 25 atmospheric species. Attention is presently given to the volume mixing ratio profiles for HCl and HF in the 15-60-km altitude region, retrieved from northern sunsets and southern sunrises. The HF/HCl ratios deduced are in good agreement with model predictions. The total atmospheric chlorine at 50 km is nearly all in the form of HCl.

Absorptions due to the nu1 band of CH3Cl have been identified for the first time in infrared solar absorption spectra of the upper troposphere and lower stratosphere. The spectral data were obtained with the ATMOS Fourier transform spectrometer on board Spacelab 3 in May 1985 during four solar occultation events near latitudes of 30 deg N, 26 deg N, 25 deg N, and 49 deg S. Volume mixing ratio profiles of CH3Cl retrieved for the altitude range 12 to 23 km at these four latitudes do not show appreciable differences. Vertical mixing ratio distributions vary from 6 x 10 to the -10th at 12 km to 3 x 10 to the -10th at 23 km with an average uncertainty of about 25 percent. The retrieved mixing ratio does not decrease with altitude as rapidly as the data obtained by in situ techniques.

Infrared solar absorption spectra of the stratosphere recorded at a resolution of 0.01/cm by the ATMOS (Atmospheric Trace Molecule Spectroscopy) instrument from onboard Spacelab 3 (04/30 to 05/6/85) have revealed the existence of many previously unobserved absorption features in the 1925 to 1960/cm and 1249 to 1255/cm regions and one at 774/cm. On the basis of comparisons with laboratory spectra, these features have been identified as belonging to the nu1, nu4, and nu6 bands of carbonyl fluoride, respectively. Volume mixing ratios of COF2 between 17 and 40 km have been deduced from analysis of the nu1 and nu6 bands.

HCl has been observed in both the troposphere and stratosphere from ground-based and airborne spectroscopic measurements of the 1-0 band at 3-micron wavelength. The results, which are specific to the HCl molecule in the gas phase, show a decreasing mixing ratio with altitude in the lower stratosphere. The stratospheric layer, which commences at about 15 km, reaches its maximum concentration at an altitude above 21 km (the limiting height of the observations to date). The local value for the volume mixing ratio at 21 km is 7 + or - 1 times 10 to the minus 10th. However, the zenith column abundance observed above 21 km implies that the mixing ratios at greater altitudes are unlikely to reach values much in excess of the local value at 21 km.

A balloon-borne high resolution Michelson interferometer recorded near infrared absorption spectra of the 1-0 fundamental vibration bands of HF and HCl in the stratosphere over Australia in March 1977. The ratio of the number density of HF to that of HCl as a function of stratospheric height was deduced from the measurements. Within estimated experimental error, the ratio is constant, its mean value being 0.1.

The vertical distribution of HCl in the stratosphere has been measured from infrared solar absorption spectra recorded with a balloon-borne interferometer. The flights were made in September, 1975, and May, 1976 at float altitudes of 40 km and 37 km, respectively, near Palestine, Texas. Concentration profiles derived from the data show an increase from 0.6 ppbv at 20 km to 1.7 plus or minus .5 ppbv in the region of 37 km. Above 37 km, the data permit only the total abundance to be determined; this value is found to be equivalent to 1.6 plus or minus .6 ppbv if the gas were uniformly mixed. The results from the two flights are closely similar, and no significant seasonal variation in the HCl concentrations can be discerned. The balloon data are consistent with the profile in the 14-21 km altitude region of the stratosphere reported earlier from U-2 observations.

Mars upper atmosphere ionized carbon dioxide and CO emission spectra in 1900-4300 A region measured by Mariner 6, observing atomic hydrogen and oxygen lines

Ultraviolet spectroscopic measurements on Mars upper atmosphere by Mariners 6 and 7

Reaction of atomic oxygen with methane studied by photolysis of ozone-methane mixtures dissolved in liquid argon

Singlet-D atomic oxygen reaction with alkanes, Coulomb integral of continuum functions, and rigid motions in conformal space-time

Molar extinction coefficients of hydrogen iodide in Schumann region to determine radiation absorption characteristics

Primary processes in ozone photolysis, determining quantum yields of photodecomposition for various wavelengths and concentrations

Reaction of oxygen atoms in the /d/ state with nitrogen

A summary report of the initial results obtained from near-infrared observations of the stratosphere from the Anglo-French SST Concorde is presented, together with the most recent results from previous flights aboard an Air Force NC-135. The measurements were made with a fast Fourier interferometer spectrometer operating in the 1.2- to 7.5-micron range of the infrared with a spectral resolution of 0.25 per cm. For the Concorde experiments, flight times and trajectories were selected which allowed the sun to be viewed near the horizon with the relative solar elevation angle held constant throughout the measurements. Results reported include the identification of features due to N2O, NO, NO2, CO, CO2, CH4, H2O and indications of their latitudinal variations.