Indonesia’s peat fires in 2026 are spreading earlier and more aggressively than most recent seasons, with a strengthening El Niño accelerating drought conditions across fire-prone regions and driving flames underground into peat deposits that can smoulder for months. The scale is already raising questions about whether the protective measures put in place after the catastrophic 2015 season are equal to the task.
Indonesia Peat Fires 2026: What the Numbers Show So Far
By 1 September 2026, NASA’s Aqua satellite had captured imagery of active fire across the archipelago. Indonesia’s Ministry of Forestry reported 946 hotspots on 31 August 2026 through its SiPongi fire-monitoring platform, which draws on data from NASA’s MODIS and VIIRS instruments. By 2 September, the fires had already released roughly 10 percent of the greenhouse gas emissions produced during the entire 2015 crisis.
According to PreventionWeb, the Indonesian government recorded more than 100,000 hectares of burned land between January and June 2026 alone. The Ministry of Forestry has also reported that approximately 50 percent of fire-affected areas in 2026 were located within peatland ecosystems, according to The Nature Conservancy. That proportion matters, because peat fires are not equivalent to ordinary forest fires: by one estimate, they produce three times more fine particulate matter than other tropical forest fires, along with five times more sulphur dioxide, three times more organic carbon, and twice as much methane and carbon monoxide.
Indonesia holds about 36 percent of the world’s tropical peatlands, concentrated in Kalimantan, Sumatra, and Papua. Under normal conditions those deposits are too waterlogged to ignite. Severe drought changes that, allowing fire to move underground and continue smouldering at relatively low temperatures far beyond the reach of conventional firefighting.
El Niño and the 2015 Comparison
NOAA assessed El Niño as present and strengthening in August 2026. The climate pattern reduces rainfall across Indonesia, and the drying becomes more pronounced when El Niño coincides with a positive phase of the Indian Ocean Dipole, which was also underway. Robert Field, a Columbia University researcher who developed the Global Fire Weather Database, told NASA Earth Observatory that conditions were tracking closely with 2015. “Indonesia is only about three weeks into its fire season, but we’re seeing fire activity track sharply upward, similar to 2015,” Field said. “The strong El Niño is making the dry season drier over the fire-prone parts of the country and exacerbating burning, just as we anticipated it would.”
The 2015 benchmark is sobering. After more than three months of burning, that season produced 1.75 billion tonnes of greenhouse gas equivalents, more than Japan emits in a full year. PreventionWeb has reported that economic losses from those fires were estimated at more than $16.1 billion. Data from Indonesia’s meteorological agency showed that about 90 percent of the country received little or no rainfall in early August 2026, conditions that echo those of 2015.
“Surface fires are less of a concern, but when fires get underground, they just won’t stop,” Field said. “They’ll keep burning until the rains come in October or November.”
Why Satellites Can Struggle to Track the Worst Fires
Satellite monitoring of Indonesia’s peat fires carries an uncomfortable irony: the most severe events can be the hardest to observe from space. MODIS and VIIRS can struggle to detect fires obscured by thick smoke or cloud cover, burning beneath the forest canopy, or smouldering underground inside peat deposits. Mark Cochrane, an ecologist at the University of Maryland Center for Environmental Science, put it plainly: “The worst smoke events, paradoxically, can be the hardest to observe from space with MODIS and VIIRS.”
A team including Shi Jun Wee, a University of Maryland graduate student, is working with NASA and MapBiomas to develop improved detection methods using shortwave infrared observations from Landsat and Sentinel-2 satellites to catch understory fires that MODIS and VIIRS may miss.
A Stress Test for Post-2015 Protections
Some of Indonesia’s current vulnerability has roots in decisions made decades ago. Cochrane points to extensive drainage of peat swamps and construction of irrigation canals during the 1990s, undertaken partly to create large rice farms, which lowered water tables and made wetland areas more combustible. Oil palm plantations have further altered the landscape.
After 2015, governments and organisations moved to reverse some of that damage through canal-blocking projects, wetland restoration, strengthened firefighting capacity, and efforts to prevent accidental ignitions. Whether those measures are sufficient is now being tested in real time. “This year will be a real stress test of the measures that were put in place after 2015,” Wee said.
For communities across Indonesia and neighbouring countries, the consequences are already concrete: Indonesian officials have warned that large portions of the population have been exposed to hazardous smoke, some schools have switched to remote learning, nine national parks have closed, and several flights have been delayed. Cochrane’s concern is that attention will fade once conditions improve. “We need sustained focus, even during the years when they aren’t as bad, to solve this,” he told NASA Earth Observatory. “These fires create a tremendous amount of emissions.”
