The world burns with amazing regularity.
But not all fires on the planet are the same. There are distinct burning seasons in many parts of the world, driven by the rainy and dry periods, agricultural practices and the spread of human population.
NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) instruments have recorded every detected fire since 2000. When all 75 million fires are mapped and colored by month, a clear geographic and temporal pattern emerges. Bands of colors light up across the world and cluster together.
Large parts of the Southern Hemisphere — including the Amazon and Africa — burn with regularity every year. According to Lauren Williams, the senior manager for Central and West African forests at the World Resources Institute, “Fires are not uncommon in most of the Congo’s forested ecosystems.” She added: “Fire is both a natural part of these ecosystems and an important land management tool in Congo that is used to clear land for agriculture, cropland management, and road clearing. Fires such as these are more common during the dry season, which lasts from roughly May to September.”
Niels Andela, a scientist at NASA’s Goddard Space Flight Center, studies fire trends across the globe. “Africa is responsible for about 70 percent of the global burned area,” he said. “Something is always burning somewhere.” Andela, along with colleagues, runs the Global Fire Emissions Database — a database that chronicles all the fires captured by NASA satellites.
But fires in South America are different. In Africa, fires are used to clear grasslands and savanna. The ecosystem there has developed to embrace and depend on fires. Many of the fires on the South American continent are on the edge of the Amazon rainforest and are burning virgin forest.
The number of fires in the Amazon varies from year to year, and based on the number of fires detected so far, 2019 is slightly outpacing the trend over recent years. While it is not clear whether this trend will continue to increase beyond normal levels, the fire season in the Amazon (south of the equator) has just begun and bears monitoring.