In 2019 and 2020, fires raged through the Amazon. Unusual in years without extreme drought conditions, the cause lies in a new upward trend in deforestation, which has reached levels not seen in over a decade. This spring, deforestation levels jumped even higher than the previous two years. This, combined with widespread drought conditions, has raised concerns about fires during this burning season, which typically begins in July and lasts up to four months.
Long-burning and intense fires are not a natural feature of the Amazon, but the normally humid conditions of the rainforest are being rapidly altered by human activity. When forests are cleared, the dead trees and brush are piled up to dry out, creating fuel that is burned to complete the cycle of deforestation. These intense fires can leak into forests and, if combined with drought conditions, can cause widespread damage. Such drought conditions are becoming more common as a result of both local deforestation and global climate change. In addition, these fires release carbon dioxide equivalent to tens of millions of cars, creating a vicious cycle that warms the planet and creates conditions for ever more intense fires.
The Brazilian federal government has authorized the use of military forces to combat deforestation over the next two months. They have also declared a nation-wide fire ban. However, fires continued to escalate under a similar ban last year, highlighting the need for more effective strategies.
Fire-fighting in the Amazon is limited by a lack of both funding and accurate information on where the risk of fire is highest. Combining available satellite data on past deforestation and fires with climatic analysis, we assess areas at highest risk of burning (dark “extreme” on map below) during Brazil’s 2021 fire season.