Indonesia is battling its worst wildfire season in 11 years as thick, toxic haze chokes cities across Kalimantan and Sumatra. Officials blame extensive peatland degradation from past food estates and agricultural drainage canals, which left carbon-rich underground soil vulnerable to severe El Niño-driven drought.
Thick orange smog has disrupted daily life across Indonesia, with air pollution indexes in districts like Katingan approaching 1,600 and Palangka Raya reaching nearly 1,300—far exceeding hazardous thresholds. The transboundary smoke has forced school suspensions in neighboring countries including Malaysia and Timor-Leste, while Indonesia’s Health Ministry reported more than 170,000 cases of acute respiratory infections in August and September alone. Frustrated residents in Palangka Raya staged a protest at the governor’s office on October 15, demanding a more effective government response to the choking conditions.
Decades of Drainage and Food Estates
While less than a third of the nation’s wildfires occur on peatlands, those underground fires generate the vast majority of the toxic haze. Environmental groups and government officials trace the crisis to decades of commercial intervention that fundamentally altered the natural properties of the peat through massive drainage projects.
As a result of longstanding interventions, the peatlands in Central Kalimantan and South Sumatra have suffered serious degradation. Massive drainage efforts were carried out, fundamentally altering the natural properties of the peat.
Hanif Faisol Nurofiq, deputy food minister, via Straitstimes
Organic material accumulated in waterlogged conditions form these porous, absorbent ecosystems. Although tropical peatlands cover only a fraction of the Earth’s land surface, they store approximately one-third of global soil carbon. Indonesia holds the world’s largest share of these critical carbon sinks. However, commercial expansion for timber, pulp and paper, rice, and palm oil has left millions of hectares dry and exposed.
Environmental group Pantau Gambut estimates that roughly 16.4 million of Indonesia’s 24.2 million hectares of peatland have been degraded. To make these soggy soils arable for industrial plantations, developers cut an estimated 285,000 kilometers of drainage canals—enough to wrap around the Earth seven times. When strong El Niño droughts strike, those dry canals turn underground peat beds into fuel for stubborn subterranean blazes.
Wildfire smoke has turned skies yellow over Indonesia’s Central Kalimantan province, as peatland fires rage near homes and farms across Borneo and Sumatra.Fuelled by slash-and-burn land clearing, the crisis, now in its third month, has led to tens of thousands of respiratory… pic.twitter.com/ubp3XOK8Ca
Zombie Fires and Carbon Emissions
Unlike surface vegetation fires, peatland fires smolder slowly beneath the surface for weeks or months. These persistent “zombie fires” are notoriously difficult to detect and extinguish, yielding thick, foul smoke laden with formaldehyde, hydrogen cyanide, ammonia, and microscopic PM2.5 particles that penetrate deep into the human bloodstream.
The environmental toll extends far beyond human health. The blazes have ravaged habitats for endangered wildlife, including orangutans, clouded leopards, Sumatran tigers, sun bears, tapirs, and Sumatran rhinos. By October 6, the fires had emitted 140.5 megatonnes of planet-warming carbon, accounting for roughly 13 percent of global fire emissions for the year according to the Copernicus Atmosphere Monitoring Service. It marked Indonesia’s highest emission level from fires since 2019.
Restoration Pledges Face Skepticism
Government officials have vowed to reverse the damage by drilling wells to rewet dried peatlands, managing water canals, and blocking drainage channels. Previous government initiatives reported rewetting 4.16 million hectares and building 45,000 canal barriers, alongside a standing moratorium on new primary forest and peatland conversion.
Yet activists question whether current institutional frameworks go far enough. Last month, the government established a new National Peatland and Mangrove Management Agency to succeed an expired mandate. Environmental campaigners have expressed concern over the agency’s title, noting its omission of explicit restoration or protection language.
Does managing in this context serve as a pretext for the state to grant new concessions on peatlands?
Belgis Habiba, forest campaigner for Greenpeace Indonesia, via Malaymail
Pantau Gambut research indicates that only 3 percent of peatland damaged by fires between 2015 and 2019 was successfully restored into forest, while more than half was converted into monoculture plantations. As local volunteer firefighters and all-women teams battle ongoing hotspots, communities continue to wait for wet weather to suppress the subterranean fires.