A method for the simultaneous retrieval of gas concentrations and an extinction spectrum of aerosols and polar stratospheric clouds from infrared transmission spectra observed in the solar occultation geometry is described. It is particularly suited to measurements by Fourier-transform spectrometers with relatively low spectral resolution (0.1-1 cm^-1). The method does not require a priori assumptions on aerosol properties; it utilizes only the fact that the wave-number dependence of aerosol extinction is much weaker than that of gas absorption. In this method, an aerosol extinction spectrum is approximated by a straight line within a relatively wide spectral range defined as mediumwindow.
© 2005 Optical Society of America
(000.4430) General : Numerical approximation and analysis
(010.1110) Atmospheric and oceanic optics : Aerosols
(010.1280) Atmospheric and oceanic optics : Atmospheric composition
(280.0280) Remote sensing and sensors : Remote sensing and sensors
(300.6340) Spectroscopy : Spectroscopy, infrared
Nobuyuki Uemura, Satoshi Kuriki, Koji Nobuta, Tatsuya Yokota, Hideaki Nakajima, Takafumi Sugita, and Yasuhiro Sasano, "Retrieval of trace gases from aerosol-influenced infrared transmission spectra observed by low-spectral-resolution Fourier-transform spectrometers," Appl. Opt. 44, 455-466 (2005)