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Using 0.002 cm resolution Fourier transform absorption spectra of an O enriched ozone sample, an extensive analysis of the v 1 + v 3 bands of the OOO and OOO isotopomers of ozone has been performed for the first time. The experimental rotational levels of the (101) vibrational states were satisfactorily reproduced using a Hamiltonian matrix that takes into account the observed rovibrational resonances. More precisely, for OOO, as for the other C 2 v -type ozone isotopomers, it was necessary to account for the Coriolis type resonances linking the (101) rotational levels with the levels of the (200) and (002) vibrational states and the Darling-Dennison interaction coupling the levels of (200) with those of (002). For the C s -type isotopomer, namely OOO, as for OOO and OOO, it proved necessary to also account for an additional Δ K a =±2 resonance involving the rotational levels from (101) and (002) (J.-M. Flaud and R. Bacis, Spectrochimica Acta Part A 54 , 3-16 (1998)). Using a Hamiltonian matrix which takes these resonances explicitly into account, precise vibrational energies and rotational and coupling constants were deduced, leading to the following band centers: v 0 ( v 1 + v 3 )=2078.3496 cm for OOO and v 0 ( v 1 + v 3 )=2098.8631 cm for OOO.

A nonlinear least-squares fitting procedure has been used to derive the stratospheric N_2O mixing ratio profile from balloon-borne solar absorption spectra and laboratory spectra near 1880 cm^−1. The atmospheric spectra were recorded during sunset from a float altitude of 33 km with the University of Denver 0.02-cm^−1 resolution interferometer near Alamogordo, N.M. (33°N), on 10 Oct. 1979. The laboratory data were used to determine the N_2O line intensities. The measurements indicate an N_2O mixing ratio of 264 ppbv near 15 km decreasing to 155 ppbv near 28 km.

Air- and nitrogen-broadened half-widths and line shifts at room temperature for more than 60 individual vibration–rotation transitions in the ν_1 fundamental band of ^16O_3 and several transitions in the ν_3 band were determined from infrared absorption spectra. These spectra were recorded at 0.005-cm^−1 resolution with a Fourier-transform spectrometer. A tunable-diode-laser spectrometer operating in the 1090–1150-cm^−1 region was also used to record data on oxygen-, nitrogen-, and air-broadened half-widths for selected individual transitions. The nitrogen- and air-broadened half-widths determined by these two different measurement techniques are consistent to within 4%. The results are in good agreement with other published measurements and calculations.

The Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment uses a Fourier-transform spectrometer on board the Space Shuttle to record infrared solar occultation spectra of the atmosphere at 0.01-cm^−1 resolution. The current version of the molecular spectroscopic database used for the analysis of the data obtained during three Space Shuttle missions between 1992 and 1994 is described. It is an extension of the effort first described by Brown et al. [Appl. Opt. 26, 5154 (1987)] to maintain an up-to-date database for the ATMOS experiment. The three-part ATMOS compilation contains line parameters of 49 molecular species between 0 and 10000 cm^−1. The main list, with nearly 700,000 entries, is an updated version of the HITRAN 1992 database. The second compilation contains supplemental line parameters, and the third set consists of absorption cross sections to represent the unresolvable features of heavy molecules. The differences between the ATMOS database and other public compilations are discussed.

A method for retrieving the atmospheric pressure corresponding to the tangent point of an infrared spectrum recorded in the solar occultation mode is described and applied to measurements made by the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier-transform spectrometer. Tangent pressure values are inferred from measurements of isolated CO_2 lines with temperature-insensitive strengths by measuring the slant-column CO_2 amount and by adjusting the viewing geometry until the calculated column matches the observed column. Tangent pressures are determined with a spectroscopic precision of 1%–3%, corresponding to a tangent-point height precision of 70–210 m. The total uncertainty is limited primarily by the quality of the spectra and ranges between 4% and 6% (280–420 m) for spectra with signal-to-noise ratios of 300:1 and between 4% and 10% for spectra with signal-to-noise ratios of 100:1. The retrieval of atmospheric pressure increases the accuracy of the retrieved-gas concentrations by minimizing the effect of systematic errors introduced by climatological pressure data, ephemeris parameters, and the uncertainties in instrumental pointing.

The final flight of the Atmospheric Trace Molecule Spectroscopy experiment as part of the Atmospheric Laboratory for Applications and Science (ATLAS-3) Space Shuttle mission in 1994 provided a new opportunity to measure broadband (625–4800 cm^−1, 2.1–16 μm) infrared solar spectra at an unapodized resolution of 0.01 cm^−1 from space. The majority of the observations were obtained as exoatmospheric, near Sun center, absorption spectra, which were later ratioed to grazing atmospheric measurements to compute the atmospheric transmission of the Earth’s atmosphere and analyzed for vertical profiles of minor and trace gases. Relative to the SPACELAB-3 mission that produced 4800 high Sun spectra (which were averaged into four grand average spectra), the ATLAS-3 mission produced some 40,000 high Sun spectra (which have been similarly averaged) with an improvement in signal-to-noise ratio of a factor of 3–4 in the spectral region between 1000 and 4800 cm^−1. A brief description of the spectral calibration and spectral quality is given as well as the location of electronic archives of these spectra.

The methodology of spectroscopic remote sensing with high-resolution Fourier-transform spectra obtained from low Earth orbit by the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment is discussed. During the course of the Atmospheric Laboratory for Applications and Science (ATLAS) shuttle missions (1992–1994) a flexible, yet reproducible, retrieval strategy was developed that culminated in the near-real-time processing of telemetry data into vertical profiles of atmospheric composition during the ATLAS-3 mission. The development, evolution, robustness, and validation of the measurements are presented and assessed with a summary comparison of trace-gas observations within the Antarctic polar vortex in November 1994.

During its first mission in 1985 onboard Spacelab 3, the ATMOS (atmospheric trace molecule spectroscopy) instrument, a high speed Fourier transform spectrometer, produced a large number of high resolution infrared solar absorption spectra recorded in the occultation mode. The analysis and interpretation of these data in terms of composition, chemistry, and dynamics of the earth's upper atmosphere required good knowledge of the molecular line parameters for those species giving rise to the absorptions in the atmospheric spectra. This paper describes the spectroscopic line parameter database compiled for the ATMOS experiment and referenced in other papers describing ATMOS results. With over 400,000 entries, the linelist catalogs parameters of 46 minor and trace species in the 1–10,000-cm^−1 region.

A description and summary of the latest edition of the AFGL HITRAN molecular absorption parameters database are presented. This new database combines the information for the seven principal atmospheric absorbers and twenty-one additional molecular species previously contained on the AFGL atmospheric absorption line parameter compilation and on the trace gas compilation. In addition to updating the parameters on earlier editions of the compilation, new parameters have been added to this edition such as the self-broadened halfwidth, the temperature dependence of the air-broadened halfwidth, and the transition probability. The database contains 348043 entries between 0 and 17,900 cm^−1. A fortran program is now furnished to allow rapid access to the molecular transitions and for the creation of customized output. A separate file of molecular cross sections of eleven heavy molecular species, applicable for qualitative simulation of transmission and emission in the atmosphere, has also been provided.

Quantitative infrared measurements of ethane (C2H6) in the upper troposphere and lower stratosphere are reported. The results have been obtained from the analysis of absorption features of the ?9 band at 12.2 µm, which have been identified in high-resolution ballon-borne and aircraft solar absorption spectra. The ballon-borne spectral data were recorded at sunset with the 0.02 cm-1 resolution University of Denver interferometer system from a float altitude of 33.5 km near Alamogordo, New Mexico, on 23 March 1981. The aircraft spectra were recorded at sunset in July 1978 with a 0.06 cm-1 resolution interferometer aboard a jet aircraft at 12 km altitude, near 35°N, 96°W. The balloon analysis indicates the C2H6 mixing ratio decreased from 3.5 ppbv near 8.8 km to 0.91 ppbv near 12.1 km. The results are consistent with the colum value obtained from the aircraft data.

The set of high-resolution infrared solar observations made with the Atmospheric Trace Molecule Spectroscopy (ATMOS)-Fourier transform spectrometer from onboard Spacelab 3 (30 April-1 May 1985) has been used to evaluate the total budgets of the odd chlorine and fluorine chemical families in the stratosphere. These budgets are based on volume mixing ratio profiles measured for HCl, HF, CH3Cl, ClONO2, CCl4, CCl2F2, CCl3F, CHClF2, CF4, COF2, and SF6 near 30° north latitude. When including realistic concentrations for species not measured by ATMOS, i.e., the source gases CH3CCl3 and C2F3Cl3 below 25 km, and the reservoirs ClO, HOCl and COFCl between 15 and 40 km (five gases actually measured by other techniques), the 30° N zonal 1985 mean total mixing ratio of chlorine, Cl, was found to be equal to (2.58±0.10) ppbv (parts per billion by volume) throughout the stratosphere, with no significant decrease near the stratopause. The results for total fluorine indicate a slight, but steady, decrease of its volume mixing ratio with increasing altitude, around a mean stratospheric value of (1.15±0.12) ppbv. Both uncertainties correspond to one standard deviation. These mean springtime 1985 stratospheric budgets are commensurate with values reported for the tropospheric Cl and F concentrations in the early 1980s, when allowance is made for the growth rates of their source gases at the ground and the time required for tropospheric air to be transported into the stratosphere. The results are discussed with emphasis on conservation of fluorine and chlorine and the partitioning among source, sink, and reservoir gases throughout the stratosphere.

Monthly mean total vertical column abundances of acetylene have been determined from series of infrared solar spectra recorded at the Jungfraujoch station, Switzerland, between June 1986 and April 1991. The data have been obtained by nonlinear least-squares fittings of the ?5 band R19 transition of C2H2 at 776.0818 cm-1. The average of 22 monthly mean total vertical columns of C2H2 retrieved during that time interval of almost 5 years was found to be equal to (1.81±0.12)×1015 molec/cm2, which corresponds to an average mixing ratio of (0,22±0.013) ppbv (parts per billion by volume) in a troposphere extending from the altitude of the station (3.58 km), up to 10.5 km. Despite the large variability found from year to year, a least-squares sine fit to the data reveals a seasonal variation with an amplitude of about ±40% of the mean; the maximum occurs during mid-winter and the minimum in the summer. The present results are compared critically with similar in-situ data found in the literature. A sinusoidal fit to all such free troposphere measurements made in-situ between 30°N and 60°N indicates good agreement in shape and phase with the seasonal variation derived above the Jungfraujoch, but their average column abundance, 2.3×1015 molec/cm2, is about 30% higher; this difference is explained on the basis of non-upwelling meteorological conditions generally prevailing during ground-based remote solar observations.

The frequent and direct remote sensing of the tropospheric ozone profile is a critical environmental measurement to be performed on a global scale by future satellite instruments. An approach has been developed for the retrieval of tropospheric ozone profiles from 9.6 μm limb‐viewing clear‐sky radiances generated for the spectral resolution and signal‐to‐noise of the Tropospheric Emission Spectrometer (TES). TES is a high‐resolution Fourier transform spectrometer under development for NASA's Earth Observing System Aura platform (http://eos-chem.gsfc.nasa.gov/). The simulated radiance spectra are calculated from northern hemisphere midlatitude lidar profile measurements. The ozone profile retrieval and the associated errors are obtained as a function of atmospheric pressure level using the method of nonlinear least squares with regularization. In order to accelerate convergence a two‐stage strategy has been applied in which the full profile retrieval has been preceded by a shape retrieval involving a smaller set of near independent parameters. Our analysis indicates that the O3profile can be retrieved from the TES limb measurements with a relative uncertainty of 5% (1σ) in the middle and upper troposphere.