Comparison of the detection of deforested areas using the ERS-1 ATSR and the NOAA-11 AVHRR with reference to ERS-1 SAR data: A case study in the Brazilian Amazon

Two coarse spatial resolution classifications of nominally 1.1 km resolution of deforested areas over a test site covering part of the south-west Amazon basin are compared. One classification is derived from data acquired by NOAA's Advanced Very High Resolution Radiometer (AVHRR) and the other from the ERS-1 Along Track Scanning Radiometer (ATSR-1). A forest/non-forest classification derived from finer spatial resolution ERS-1 Synthetic Aperture Radar (SAR) data is used as a reference for the comparison. Specific patterns of deforestation in the area are identified and their depiction on each of the coarse spatial resolution datasets is examined in relation to their depiction on the fine spatial resolution classification. The results show that significant differences exist between the two coarse spatial resolution classifications and that special rigorous integration methodologies will have to be developed before the results from either source can be used interchangeably with those from the other.