Monitoring Amazonian Wildfires

Forest fires are not uncommon during Brazil’s dry season, which lasts from approximately May to September. But wet weather patterns in large areas of the Amazon rainforest typically prevent fires from spreading and becoming more severe. However, circumstances have been different this year.

The Global Fire Emissions Database (GFED) confirms that fires in 2019 are more intense than in previous years. According to a GFED 2019 Fire Forecast report, from May 1 through Sept. 30, fire detections approximated more than 200,000 in the Amazon, the highest count since 2012.

Igniting Factors

“There are conditions this year that would make the region more vulnerable to drought, and we are on the lookout to see how those conditions will develop across the Amazon throughout the year,” NASA remote sensing specialist Douglas Morton said in an Aug. 30 interview with ScienceMag.org.

The cause of the fires, according to an article published by the University of Melbourne, is a combination of three main factors—deforestation, routine farming practices, and climate change.

Brazil’s National Space Research Institute reported more than 6,000 square kilometers of deforestation had occurred in the Amazon rainforest by Aug. 31—a sharp increase from 3,368 square kilometers in 2018. Vast areas of the rainforest are cleared each year for cattle pastures and soybean farms, infrastructure development, and illegal logging.

Illegal logging, in particular, is becoming increasingly widespread in Brazil. Though it is not the principal cause of deforestation or wildfires, it does allow more sunlight to reach the forest floor, creating drier conditions more prone to ignition.

Severe droughts have also caused areas of the rainforest to become drier. Therefore, planned burning, which is a common practice among many farms, becomes more dangerous.

Sensing the Flames

The recent spike of wildfires in the Amazon has been closely monitored from space via remote sensing tools. Recent advances in satellite technology, the Internet of Things (IoT), and GIS tools aid in tracking fire location, intensity, and direction.

Satellites are often the first to detect fires burning in remote regions of the Amazon. A wildfire, according to Morton, will trigger multiple pixels in a satellite image as thermal anomalies.

“Isolated detections may actually represent a combination of many small fires in the same location. The timing, location, and amount of energy released by the fire all provide information for scientists and fire managers,” Morton told ScienceMag.org.

The Moderate Resolution Imaging Spectroradiometer (MODIS), mounted aboard NASA’s Terra and Aqua satellites, measures both light amplitude and wavelength of wildfires—calculating approximately 230,000 wildfires in the Amazon as of Oct. 7.

In recent years, the Brazilian Federal Police have also leveraged satellite imagery to provide evidence of environmental crimes such as unlawful logging that could lead to wildfires. Franco Perazzoni, head of the Brazilian Federal Police GEOINT Service, said in a virtual presentation at USGIF’s recent GEOINTegration Summit: “Satellite imagery is not used as an intelligence tool but as evidence to these crimes.”

Another effective way to track forest fires is through mapping. But converting satellite images into actionable intelligence requires the integration of GIS. Each image, which contains timestamp and location coordinates, must be quickly cross-referenced with images from other satellites before first responders are deployed.

A GIS platform can then import this data and perform a series of steps to improve location accuracy and visual performance as well as to prepare the data for interactive map presentations.

Such interactive maps are also now available to anyone with an internet connection. NASA operates a service called Fire Information for Resource Management System (FIRMS), whichprovides near real-time tools for the mapping and management of wildfires. FIRMS takes thermal signature anomalies detected by the Aqua, Terra, and Suomi satellites and plots them onto a global basemap within three hours of a satellite passing overhead.

As more widespread and severe forest fires continue to occur in the Amazon and elsewhere around the world, monitoring and detection methods employed by space agencies and local authorities will continue to improve the speed and accuracy of mitigation, detection, monitoring, and response.

Image Courtesy of NASA