Each year farmers in Indochina (this image) and across the globe must get their fields ready for the new planting season. One way that they do this is by setting fires to the fields to rid the ground of detritus from the previous year. The location, widespread nature, and number of fires in this satellite image from Indochina suggest that these fires were deliberately set to manage land.
While fire helps enhance crops and grasses for pasture, the fires also produce smoke that degrades air quality. Each hot spot, which appears as a red mark, is an area where the thermal detectors on the Suomi NPP satellite recognized temperatures higher than background. When accompanied by plumes of smoke, as in this image, such hot spots are diagnostic for fire. The smoke released by any type of fire (forest, brush, crop, structure, tires, waste or wood burning) is a mixture of particles and chemicals produced by incomplete burning of carbon-containing materials. All smoke contains carbon monoxide, carbon dioxide and particulate matter or soot.
NASA’s Suomi NPP satellite collected this natural-color image using the VIIRS (Visible Infrared Imaging Radiometer Suite) instrument on March 18, 2016. Actively burning areas, detected by MODIS’s thermal bands, are outlined in red. NASA image courtesy Jeff Schmaltz LANCE/EOSDIS MODIS Rapid Response Team, GSFC. Caption by Lynn Jenner