Thousands of fires burned across Indochina in late March, 2014, as agricultural fire season heated up. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite captured a dramatic true-color image of the red-speckled landscape on March 30.
The heaviest clusters of red hotspots congregate in Myanmar (Burma) and in Bangladesh, in the west of the image. A dense cluster also can be seen in Laos. Thailand and Vietnam (west and east of Laos, respectively) are more lightly speckled in red. Each hotspot marks an area where the thermal sensors on the MODIS instrument detected temperatures higher than background. When combined with smoke, such hotspots are diagnostic for actively burning fires.
Seasonal burning of cropland and pastures is common in this region, and peaks with the changes of the season – in early spring and late winter. Deliberately set fires, which are usually well-controlled, are used for pest and weed control, to open new land, to prepare fields for planting, and to freshen pasture. Burning of crop residue can also provide short-term fertilization.
Although controlled fire can bring benefits, it also brings hazards. Any fire can slip out of control and cause severe damage as a wildfire. And smoke resulting from fire can cause respiratory disease in both humans and livestock. When burning becomes widespread, air quality plummets and risk for fire-related illness increases.