Validation of MODIS Active Fire Products With Coincident ASTER Data

Satellites provide valuable information for the large-scale monitoring of biomass burning over the globe. However, the accuracy of the satellite-derived fire products needs to be determined. An active fire product from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on board the polar orbiter Terra satellite has been available since 2000. A unique feature of the Terra satellite is the availability of coincident high resolution data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). In this study we used the elevated signal in the 30 m resolution ASTER channel 9 at 2.4 micron to characterize fires within the 1-km MODIS pixels. The probability of MODIS detection was determined by logistic regression as a function of sub-pixel fractional fire coverage and spatial heterogeneity. Examples of individual fires and summarized statistics will be presented for various regions of the globe. The effects of algorithm changes on product accuracy will also be discussed. This work is being undertaken in the framework of the international GOFC/GOLD-Fire program. Involvement of regional scientists in validation of satellite data products is encouraged and will help build a user community informed on the capabilities and limitations of a given product for subsequent application.