| Autor: |
Jean-Michel Hartmann, R. Rodrigues, L. Bonamy, J. Walrand, G. Blanquet, A. Valentin, R. Le Doucen, K.W. Jucks, Wesley A. Traub, B. Khalil, Nelly Lacome, C. Camy-Peyret |
| Rok vydání: |
1999 |
| Předmět: |
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| Zdroj: |
Journal of Quantitative Spectroscopy and Radiative Transfer. 63:31-48 |
| ISSN: |
0022-4073 |
| DOI: |
10.1016/s0022-4073(98)00133-2 |
| Popis: |
A theoretical model based on the energy-corrected sudden approximation is used in order to account for line-mixing effects in infrared Q branches of symmetric isotopomers of CO2. Its performance is demonstrated by comparisons with a large number (about 130) of CO2–N2 and CO2–O2 laboratory spectra recorded by several instrument setup: nine Q branches of different vibrational symmetries lying between 4 and 17 μm are investigated in wide ranges of pressure (0.05–10 atm) and temperature (200–300 K). The model is used to generate a set of suitable parameters and FORTRAN software (available by ftp) for the calculation of the absorption within 12C16O2, 13C16O2, and 12C18O2 infrared Q branches under atmospheric conditions, which can be easily included in existing radiance/transmission computer codes. Comparisons are made between many (about 280) computed atmospheric spectra and values measured using two different balloon-borne high-resolution Fourier transform instruments: transmission (solar occultation) as well as radiance (limb emission) measurements of seven Q branches between 12 and 17 μm for a large range of atmospheric air masses and pressure/temperature conditions have been used, including the ν2 band of both 12C16O2 and 13C16O2. The results confirm the need to account for the effects of line-mixing and demonstrate the capability of the model to represent accurately the absorption in regions which are often used for temperature/pressure sounding of the atmosphere by space instruments. Finally, quantitative criteria assessing the validity of the widely used Rosenkranz first-order approximation are given. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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