IMG evidence of chlorofluorocarbon absorption in the atmospheric window region 800-900 cm super(-1)

• Published in: Journal of quantitative spectroscopy & radiative transfer 2002-03, Vol.72 (5), p.623-635
• Main Authors: Lubrano, A M, Masiello, G, Serio, C, Matricardi, M, Rizzi, R
• Format: Article
• Language: English
• ISSN: 0022-4073

Infrared spectra recorded by the interferometric monitoring of greenhouse gases sensor have been analysed to assess the effect of the molecule CCl sub(3)F in the atmospheric window region 800-900 cm super(-1). The analysis has been carried out at a sampling rate of 0.25 cm super(-1) which is typical of next generation space borne infrared sensors such as the European infrared atmospheric sounding interferometer. It has been found that at this spectral resolution absorption by CCl sub(3)F is clearly evident and mostly effective in the spectral range 840-860 cm super(-1) where it may account for up to 1 K depletion in the brightness temperature spectrum. It will be shown that a CCl sub(3)F concentration of 270 pptv (mixing ratio) fits very well to the spectral observations. Our findings show that chlorofluorocarbons may play an interfering role in determining surface or close to surface geophysical parameters. On the other hand, the fact that these compounds are clearly identifiable in infrared spectra opens the way to an effective monitoring of their presence and abundance from space.