Active Fires As Observed by VIIRS, January-September 2021

This visualization shows active fires as observed by the Visible Infrared Imaging Radiometer Suite, or VIIRS, between January 1 and September 24 2021. The VIIRS instrument flies on the Joint Polar Satellite System’s Suomi-NPP and NOAA-20 polar-orbiting satellites. Instruments on polar orbiting satellites typically observe a wildfire at a given location a few times a day as they orbit the Earth from pole to pole. VIIRS detects hot spots at a resolution of 375 meters per pixel, which means it can detect smaller, lower temperature fires than other fire-observing satellites. Its observations are about three times more detailed than those from the MODIS instrument, for example. VIIRS also provides nighttime fire detection capabilities through its Day-Night Band, which can measure low-intensity visible light emitted by small and fledgling fires. This visualization uses data from the Suomi-NPP VIIRS instrument, and will be updated periodically until the end of 2021.