Wildfires currently burning large swathes of land in Indonesia are on track to produce emissions on a par with the country’s most-intense fire season this century, according to experts.
Data from the Global Fire Emissions Database reveals that, as of 7 September, fires in Indonesia produced 76m tonnes of carbon (MtC) in 2026.
This puts 2026 on the same trajectory as 2015, when fires burned 2.6m hectares of land across the country and generated a total of 333MtC.
Dr Guido van der Werf, a researcher at Wageningen University in the Netherlands, tells Carbon Brief that the fires in Indonesia are “more or less on track” to reach levels seen 11 years ago.
Parts of the country – including the eastern province of Papua – are “burning more than they’ve ever burned”, he says.
Indonesia is no stranger to emissions-intensive fires. Research has estimated that the record 1997 fire season generated carbon emissions equivalent to 13-40% of all global fossil-fuel emissions that year.
Meanwhile, a separate study that looked at carbon dioxide (CO2) emissions from the 2015 fires in south-east Asia – which primarily burned Indonesia – found they were greater than the total of the EU’s fossil-fuel emissions that year. The “severe haze” from the fires has been linked to more than 100,000 premature deaths across the region.
El Niño influence
As in 2015 and in 1997, this year’s Indonesian fires come during an El Niño year.
The naturally-occurring climate phenomenon, linked to ocean temperatures in the Pacific, periodically drives up temperatures and dries out land in Indonesia – creating the conditions for fires so immense that they imprint on global emissions.
Scientists are projecting that this year’s El Niño – which started in June and is expected to last into 2027 – will be one of the most intense on record.
Dr Mark Parrington, a senior scientist from the Copernicus Climate Change Service explains:
“From August until the end of October [to] November is the dry season in Indonesia. We do normally see fire around this time of year, but nowhere near the scale that we’ve seen this year, or indeed any of the previous El Niño years”.
Dr Nisa Novita, strategic lead for peatland at Indonesian environmental NGO Yayasan Konservasi Alam Nusantara, tells Carbon Brief that El Niño “does not directly cause most fires”, but acts as a “major amplifier by creating hotter and drier conditions, making fires easier to ignite, spread faster and much harder to control”.
Studies have shown that fires in Indonesia often occur where there has been significant land clearance and peatland drainage for agriculture and palm oil plantations. These practices create a dry landscape that is highly flammable during times of drought.
Van der Werf says the scale of this year’s fires – and whether they will end up being more intense than 2015 – will depend on the length of this year’s El Niño event, as well as the effectiveness of recent peatland conservation efforts.
Novita explains that Indonesia’s fires are heavily emissions-intensive due to its large tropical peatland ecosystem:
“When peatlands are degraded and drained due to canal development for agriculture, the water table drops, making the peat dry and highly flammable especially during dry seasons or El Niño events, like now.
“Unlike fires in dry ecosystems, peat fires can smolder underground, so the soil itself becomes readily available fuel.”
Extensive peatland restoration efforts in Indonesia in recent years have been credited with reducing the number of fires during the 2019 El Niño.
After the catastrophic fires in 1997-98, the Indonesian government introduced a range of measures designed to strengthen peatland protection and restoration through dedicated institutions and regulations. This included the introduction of a moratorium on licenses to convert forests and peatlands into plantations and logging areas.
In the aftermath of the 2015 fires, it established an official peatland restoration agency, which was given an additional mandate for mangrove restoration in 2021. This agency was dissolved last year. Novita says:
“We have learned and improved…But the question is: is it enough? Or are we still underestimating the risk that degraded peatlands pose, especially when we face another El Niño?”
Van der Werf says it remains unclear from the 2026 fire data how great an impact recent efforts to restore peatland in Indonesia have had on reducing the impact and spread of the fires:
“I had hoped that this year Indonesia would be relatively quiet, even though we have a big El Niño…You could argue if those regulations worked, then this wouldn’t be a big fire [season], even though it [has been] very dry.
“This is maybe the case in Sumatra [which has seen a quiet fire season], but definitely not in other regions. Papua [a region of Indonesia] and [neighbouring country of] Papua New Guinea – those are the new frontiers. They are basically going through the same thing that Sumatra went through 20 years ago.”