Testing the local applicability of MODIS BRDF parameters for correcting Landsat TM imagery

Abstract

Landsat Thematic Mapper (TM) imagery is widely used for large scale multi-temporal monitoring of the land surface. One source of variability in this imagery, which is not related to variation in the land surface, is the result of the bi-directional reflectance distribution function (BRDF). This causes variation in the measured reflectance as a function of the angular configuration of the sun and sensor. To remove this variation from the imagery, a correction can be applied for BRDF. Some authors have proposed the use of the BRDF parameterization derived for the Moderate Resolution Imaging Spectroradiometer (MODIS; NASA, Washington, DC, USA) instrument as a means of correction for BRDF in Landsat TM imagery. However, since the spatial scale of the two instruments is substantially different, it is not clear up to what extent the MODIS BRDF parameters are applicable to Landsat TM. This study provides a direct empirical test of this, over the eastern Australian landscape, and tests whether the MODIS BRDF parameters are applicable to characterize BRDF at a local scale of a Landsat TM pixel, or simply at a global scale. The results suggest that the MODIS BRDF parameters effectively characterize the BRDF of the Landsat imagery at a global average scale, but, at least in the Australian context, do not capture any further information about the BRDF of more local regions, or individual Landsat pixels.

Acknowledgments

The author would like to thank Tony Gill, Sam Gillingham, John Armston and Stuart Phinn for advice and discussion on the draft of this paper, and the anonymous reviewers for highlighting areas of the text which required clarification.