Satellite monitoring of different vegetation types by differential optical absorption spectroscopy (DOAS) in the red spectral range

T. Wagner (1) , S. Beirle (1) , M. Grzegorski (1) , U. Platt

1 Institut für Umweltphysik [Heidelberg]

A new method for the satellite remote sensing of different types of vegetation and ocean colour is presented. In contrast to existing algorithms, our method analyses weak narrow-band reflectance structures (i.e. "fingerprint" structures) of vegetation in the red spectral range. It is based on differential optical absorption spectroscopy (DOAS), which is usually applied for the analysis of atmospheric trace gas absorptions. Since the spectra of atmospheric absorption and vegetation reflectance are simultaneously included in the analysis, the effects of atmospheric scattering and absorption are automatically corrected. The inclusion of the vegetation spectra also significantly improves the results of the trace gas retrieval. The global maps of the fitting coefficients for the vegetation spectra (indicating the fraction of the observed ground scene covered by vegetation) illustrate the seasonal cycle of different vegetation types. In addition to the vegetation distribution on land, they also show patterns of biological activity in the oceans. Our results indicate that improved sets of vegetation spectra might lead to more accurate and more specific identification of vegetation type in the future.

Domaines: Océan, Atmosphère

T. Wagner, S. Beirle, M. Grzegorski, U. Platt. Satellite monitoring of different vegetation types by differential optical absorption spectroscopy (DOAS) in the red spectral range. Atmospheric Chemistry and Physics Discussions, 2006, 6 (4), pp.7945-7958. ⟨hal-00302071⟩