Analysis of Firepower in Amazon Forest by Satellite: Evaluation with MODIS and VIIRS Sensors

Forest fires in the Amazon rainforest pose a critical environmental challenge, with impacts on biodiversity, atmospheric composition, and climate regulation. Fire activity has intensified in recent decades due to climate variability and increasing anthropogenic pressure, raising concerns about a potential shift of the Amazon from a carbon sink to a carbon source. This study analyzes the spatial and temporal variability of fire activity across the Amazon basin, with a focus on the Brazilian region, over the period 2001–2022. The analysis is based on satellite-derived active fire data from NASA’s Fire Information for Resource Management System (FIRMS), obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Visible Infrared Imaging Radiometer Suite (VIIRS). Fire Radiative Power (FRP) is used as a proxy for fire intensity and combustion processes. The observed increase in fire activity post-2012 is primarily attributed to the deployment of the VIIRS sensor, which offers superior sensitivity for detecting small-scale and low-intensity fires Pronounced peaks of fire activity are observed in 2004, 2005, 2007, and after 2019. Statistical analyses reveal strong interannual variability and cyclical behavior in FRP, linked to variations in drought conditions, precipitation, land-use change, and environmental policy. Overall, the study highlights the value of multi-sensor satellite observations for long-term fire monitoring on the Amazon.