Science1 publisher3 min readPublished
Satellite monitoring puts Indonesia's burned area at more than four times the last official count
Nusantara Atlas satellite data put Indonesia's burned area at nearly 896,000 hectares by end-August, against an official 202,000 through July. The counts cover different months and methods, so the gap cannot yet be split between August burning and undercounting.
The Scientist · Science desk
What happened
- The official January-to-July figure was already 69% above the same period last year, an area roughly three times the size of Jakarta.
- South Papua was the hardest-hit province, with more than 168,000 hectares burned by August according to Nusantara Atlas.
- President Prabowo Subianto last week ordered a new agency to manage tropical peat and mangrove ecosystems and carry out fire prevention.
- Indonesia's health ministry says respiratory illness cases have passed 170,000 in haze-hit provinces of Sumatra and Borneo.
- Haze has periodically closed schools in Malaysia's Sarawak state and has reached Singapore, the Philippines and southern Thailand.
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Why it matters
- contradiction Peat hot-spot counts rank this season above 2015, but the area estimate puts it under half of 2015's burn. How severe officials say the season is will depend on which measure they choose.
- constraint Any response sized to the published figure is sized to July. If the satellite method matches the official one, about 694,000 hectares of burning fall outside it.
- precedent Indonesia let its post-2015 peat agency lapse in 2024. The new one will be judged on whether its mandate outlasts an El Niño forecast to run into early 2027.
The thing the ratio between the two counts does not tell you is when the land burned. The satellite estimate is about 4.4 times the official figure [1], but the two cover different windows. The government's runs from January to July [1]. Nusantara Atlas, a project that uses satellite monitoring, counts to the end of August [4]. According to AFP, the official series has not been updated since July, and the burning has worsened in the meantime [2].
If both methods measured burned land the same way, the difference would mean roughly 694,000 hectares burned in August alone [2]. That is about 3.4 times the official total for the seven months before it [3]. A very bad August is plausible. This El Niño is forecast to be among the strongest in decades and to last until early 2027 [7]. The report does not describe how either figure is compiled. Without a Nusantara Atlas estimate for January to July, the gap cannot be split between an August surge and a difference in counting. On this evidence the official figure is certainly out of date; whether it is also an undercount cannot yet be measured.
A second yardstick complicates the comparison with the last great fire year. The NGO Pantau Gambut counted more than 212,000 hot spots inside peat ecosystems in the first eight months of this year, more than double the count in the strong El Niño of 2015 [11]. Fires in 2015 burned more than 2 million hectares and caused an estimated $16.1 billion in damage, according to the World Bank [16]. This year's satellite area estimate through August is at most about 45% of that 2015 total [4]. Hot spots are detections and hectares are area. The 2026 season is also unfinished, so the two measures cannot yet say whether this year is worse.
Peat is why the fires resist control. It is normally waterlogged, but across much of Indonesia it has been drained so the land can be planted, and once alight it can smolder and reignite for days [10]. "El Niño isn't actually the cause, but it's a trigger. There still needs to be an ignitor," IPB University forestry lecturer Ati Dwi Nurhayati told AFP [8]. "We know that in peatlands, almost 100% (of the fires) was caused by human activity," she said [9].
In South Papua, the NGO Yayasan Pusaka Bentala Rakyat said fires had been detected inside a large-scale government food estate project, according to local media reports cited by AFP [6].
Firefighters, cloud seeding and water bombing have had limited success, AFP reports [12]. Authorities have revoked the permits of five companies accused of contributing to the fires and frozen dozens more [13].
The new agency has a predecessor. Indonesia set up a peat body after the 2015 fires, extended it to mangroves in 2020, and let its mandate expire in 2024 [15]. "The important thing is to ensure that this agency's mandate can answer the issue of peat management, not just introduce a new structure," Pantau Gambut senior campaigner Putra Saptian said in a statement [17].
What to watch
- An updated government burned-area figure covering August, and how close it comes to Nusantara Atlas's 896,000 hectares.
- A Nusantara Atlas estimate for January to July alone, which would show whether its method runs higher than the official count over the same months.
- The legal mandate and term Prabowo's decree gives the new peat and mangrove agency.