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This study shows the use of dual-polarized L-band Synthetic Aperture Radar (SAR) data acquired by the Advanced Land Observing Satellite (ALOS) Phased Array type L-band Synthetic Aperture Radar sensor (PALSAR) system for differentiation between primary forest and new deforestation fronts. Results showed that the new deforested areas are not unequivocally detected in either of the single bands individually. Although most of the recent deforestation appears brighter than mature forests in the HH band, the identification of new deforestation using only this band depends on the stage of the clearing process. Then, the contribution of the HV band through a normalized difference index (NDI) is important for detection of the new deforested fronts. Results indicate that the method can be used as the basis for an operational programme to monitor deforestation in the Brazilian Amazonia. [ABSTRACT FROM AUTHOR]

The objective of this paper is to present a method for mapping burnt areas in Brazilian Amazonia using Terra MODIS data. The proposed approach is based on image segmentation of the shade fraction images derived from MODIS, using a non-supervised classification algorithm followed by an image editing procedure for minimizing misclassifications. Acre State, the focus of this study, is located in the western region of Brazilian Amazonia and undergoing tropical deforestation. The extended dry season in 2005 affected this region creating conditions for extensive forest fires in addition to fires associated with deforestation and land management. The high temporal resolution of MODIS provides information for studying the resulting burnt areas. Landsat 5 TM images and field observations were also used as ground data for supporting and validating the MODIS results. Multitemporal analysis with MODIS showed that about 6500 km2 of land surface were burnt in Acre State. Of this, 3700 km2 corresponded to the previously deforested areas and 2800 km2 corresponded to areas of standing forests. This type of information and its timely availability are critical for regional and global environmental studies. The results showed that daily MODIS sensor data are useful sources of information for mapping burnt areas, and the proposed method can be used in an operational project in Brazilian Amazonia. [ABSTRACT FROM AUTHOR]

The principal aim of this Letter is to evaluate the usefulness of Spectral Mixture Analysis (SMA) for estimating the area burned by forest fires in Mediterranean countries using National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) unitemporal data. The results show that the method, using an image acquired just after the fire occurrence, is capable of discriminating burned area accurately (Kappa coefficient >0.76). [ABSTRACT FROM AUTHOR]