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High-resolution water vapor absorption spectra have been measured at room temperature in the 8800-11,600cm -1 spectral region. They were obtained using the mobile BRUKER IFS 120M Fourier transform spectrometer (FTS) from ULB-SCQP coupled to the 50m base long multiple reflection White type cell in GSMA laboratory. The absorption path was 600m and different H 2O/HDO/D 2O mixtures were used. Measurements of line positions, intensities and self-broadening coefficients were performed for the HD 16O isotopologue. 6464 rovibrational assignment of the observed lines was made on the basis of global variational predictions and allowed the identification of new energy levels. 3ν 3, 2ν 1+ν 3, 3ν 1+ν 2, ν 1+2ν 3 and 2ν 2+2ν 3 are the five strongest bands. The present paper provides a complementary data set on water vapor for atmospheric and astrophysical applications. © 2012 Elsevier Ltd., SCOPUS: ar.j, info:eu-repo/semantics/published

Fast scan submillimeter spectroscopy (FASSST) cavity ring down spectroscopy has been used to measure the dry air continuum, and separately its individual component parts, at ∼6000 frequencies in the spectral region between 170 and 260 GHz. These measurements have been made at pressures that range from 0 to 3 atmospheres and in the temperature range between 230 and 320 K. For several of the components these are the first measurements made at or near atmospheric conditions. These measurements contain all of the information necessary to parameterize the observed absorptions in terms of the fundamental line and continuum interactions without the need to import external parameters. The inversion of this analysis makes possible the calculation of atmospheric absorption with meaningful uncertainties over this spectral region for temperatures and pressures of atmospheric interest.

The selection of the number of k-interval is a foundation to correlated k-distribution method and the problem of how to do it still remains unsettled. It is pointed out by numerical computation in this work that choosing the number of k-interval is a major factor affecting accuracy and speed in radiative calculation. To increase the number of k-interval is an efficient method to improve the accuracy. However, it is found by this study that there exists a saturation of the accuracy to an increase of the number. The optimal rules on the number of k-interval choosing are proposed in the paper. Then, five versions on atmospheric absorption by gases appropriate for GCMs are given according to them.

Paper associated with the CWVC (Clouds, Water Vapour and Climate) dataset held on the CEDA archive.

Isotopic ozone lines of 16O16O17O and 16O17O16O in the 5 μm region are identified for the first time in balloon-borne high-resolution (0.003 cm −1 ) solar absorption spectra. A few of these lines also are observed in ground-based spectra. These lines need to be included in analysis of atmospheric absorption spectra, in addition to the recently identified 16 O 16 O 18 O , 16 O 18 O 16 O and 16O12C34S lines in this region.

In an effort to retrieve accurate rotational temperatures from hydroxyl (OH) nightglow spectra, a computer model of atmospheric absorption has been combined with a Doppler model of the Λ-doubled OH rotational lines in order to derive transmission coefficients for the individual lines. Atmospheric transmission coefficients have been tabulated for the first three to four major P, Q and R-branch rotational lines of the OH Meinel (4,2), (3,1), (7,4), (6,2) and (8,3) bands. These coefficients have been calculated for OH Doppler temperatures over the typical mesospheric range from 150 to 250 K and for mid- and high-latitude, winter and summer conditions. Finally, the resulting atmospheric transmission coefficients have been applied to a low-noise, near-infrared data set obtained during the high-latitude summer under quiet geophysical conditions. It is shown that these coefficients correct the selective absorption of individual rotational lines in different OH vibrational bands, and thus, resolve the differences in the rotational temperatures inferred from the different vibrational levels of the uncorrected spectra.

The nonlinear iterative deconvolution method is discussed and difficulties in restoring the shapes of spectral lines are noted. Using Newton's iterative method and line-shape theory, an improved method is developed. Numerical experiments are described for the absorption spectra of different line shapes. The results show that our method produces satisfactory deconvolved results for both single- and multiple-line absorption spectra. When pressure broadening is dominant, we find significant improvement for the deconvolved spectra with our procedure.

High resolution band-model parameters are presented for the 4.3 μm CO 2 band from 200 to 3000°K. Comparisons are made to experimental data covering this same temperature range. The band model predictions and data are shown to be in good agreement. Application of the band model parameters to plume emission and atmospheric absorption calculations in the CO 2 fundamental band head region (2380–2400 cm -1 ) is discussed. Line-by-line and band-model plume signature predictions are compared for an aircraft and a rocket plume over 0, 0.5, and 5 km atmospheric paths. The line-by-line and band-model predictions for the 0 and 0.5 km paths are in good agreement. For the 5 km path, the band-model overestimates the atmospheric transmission by a factor of two. The reason for this overprediction is discussed and a correction is presented which improves the accuracy of the band-model transmission calculations.

A new method is described for the application of band models to an observed absorption spectrum. It is shown how the appropriate model (Elsasser or statistical) is selected by a simple analysis of the observed spectral data. Once the model has been chosen, the two main parameters of each model are derived by the use of curves of growth. The method is applied to the following atmospheric bands: N 2 O (at 4·5μ), CO (at 4·7μ) and H 2 O (at 6·3μ). For each band the parameters of the appropriate band model are calculated for a large number of frequencies in the band.

By comparing computed and observed spectra over the region 4210–4310 cm-1, it is shown that the H2O line parameters calculated by Flaud and Camy-Peyret for this region represent a significant improvement over those listed in the revised version of the AFCRL Atmospheric Absorption Line Parameter Compilation.