Indonesia's 2015 Forest and Peat Fires: Causes, Haze and Toll

Indonesia’s 2015 Forest and Peat Fires: An Environmental Disaster

Between June and October 2015, fires burned across roughly 2.6 million hectares of Indonesia, mostly in Sumatra and Kalimantan, the Indonesian part of Borneo. A large share burned in drained peatland, where the ground itself smoulders for weeks. The smoke created a regional haze that closed schools, grounded flights and sickened people in Indonesia, Malaysia, Singapore and beyond. The World Bank later put the cost to Indonesia at about US$16.1 billion, around 1.9% of the country's GDP.

At the time, the writer George Monbiot called it, in a Guardian column of 30 October 2015, "almost certainly the greatest environmental disaster of the 21st Century – so far." Here is why the 2015 fires were so destructive, who and what they harmed, and what has changed since.

Why peat fires are so hard to stop

Tropical peat forms in permanently waterlogged swamp forests. Fallen leaves, roots and wood cannot fully rot in the wet, oxygen-poor ground, so they build up over thousands of years into thick layers of organic soil. In Indonesia these peat beds can be up to about 20 metres deep, and some inland peat began forming more than 26,000 years ago. The Sabangau forest in Central Kalimantan sits on one of these domes.

Undisturbed, this peat is too wet to burn. Once it dries out, it becomes fuel. Fire can creep underground, smouldering slowly beneath the surface, hidden from view and hard to reach with water. Peat fires can burn for weeks or months and give off dense, low smoke heavy with fine particles and toxic gases. That is why 2015 was not simply a forest fire season: in many places the land itself was burning.

Tropical peatlands cover only about 0.25% of Earth's land surface but hold an estimated 50 to 70 billion tonnes of carbon. When they burn, that ancient carbon goes into the atmosphere.

Drainage, plantations and El Niño

The fires were set by people, not lightning. Fire is the cheapest way to clear land for crops, whether by large companies or by smallholders. Over decades, much of Indonesia's peat swamp forest was logged and cut through with canals that drained the water away, partly to prepare land for oil palm and pulpwood plantations. One notorious example, the Mega Rice Project begun in 1996, dug more than 4,000 km of channels through Borneo's peat before being abandoned.

Monbiot summed up the logic of land clearing bluntly: "The easiest way to clear the land is to torch it." In a normal year, the wet season limits the damage. In 2015, a strong El Niño brought a long drought, and burns that might once have been contained spread out of control.

The question of blame is more complicated than it is often presented. One study found that most fire emissions in 2015, about 59% in Sumatra and 73% in Kalimantan, came from outside the boundaries of timber and palm oil concessions. Campaigners argue that plantation expansion still drives the problem, because it creates the drainage, roads and land markets that make burning attractive. The World Bank estimated that fires on peatland cleared for palm oil accounted for about a third of the blazes.

The haze: cities, health and schools

The smoke drifted across Southeast Asia from late June into October. In Palangkaraya, the capital of Central Kalimantan, the Pollutant Standards Index reached 1,986 on 22 September 2015, several times above the threshold for "hazardous" air. Visibility in some cities fell to a few dozen metres, and daytime looked like dusk.

Midafternoon in Palangkaraya, Central Kalimantan, during the 2015 haze, in an image shared on Twitter at the time.

Another view of Palangkaraya under the smoke. Readings there were among the worst recorded in the region.

Indonesian authorities reported more than 140,000 cases of respiratory illness and a number of deaths, including children, as well as fatal road accidents caused by poor visibility. A 2016 study by researchers at Harvard and Columbia estimated more than 100,000 premature deaths across the region from the smoke, a figure that Indonesian, Malaysian and Singaporean health authorities disputed. Either way, the health burden was severe.

Schools closed in Indonesia, Malaysia and Singapore. In Malaysia alone, millions of pupils were affected by closures, and Singapore shut all primary and secondary schools for several days in late September. Indonesia declared states of emergency in several provinces, deployed thousands of troops to fight fires, tried cloud seeding and accepted help from neighbouring countries.

Wildlife: orangutans and the species at risk

Borneo and Sumatra are among the richest places on Earth for wildlife, and the fires reached deep into habitat already shrunk by logging and plantations. Monbiot listed orangutans, clouded leopards, sun bears, gibbons, the Sumatran rhinoceros and the Sumatran tiger among the threatened species driven from much of their range.

Orangutans in the haze at a Borneo Orangutan Survival Foundation camp on 5 October 2015. Photo: Antara Foto/Reuters.

Orangutans were the face of the crisis. The Bornean orangutan is listed as Critically Endangered, with an estimated population of about 104,700 in the wild, and Sabangau alone holds several thousand. Rescue groups evacuated orphaned and injured apes from burning areas, and some experts warned in 2015 that as many as 20,000 orangutans could be pushed out of their forest refuges, an estimate that was never confirmed as a final toll. Gunung Palung National Park in West Kalimantan, home to an important wild population, was reportedly among the areas affected.

The Orangutan Tropical Peatland Project (OUTROP), which works in Sabangau, helped fight fires on the ground and appealed for support. Its footage from Borneo appears below.

The scale of the emissions

Because peat is so rich in carbon, the 2015 fires had a global climate impact. The Global Fire Emissions Database estimated that the Indonesian fires released about 600 million tonnes of greenhouse gases, roughly equivalent to Germany's annual output. The World Resources Institute calculated that on 26 days in September and October, Indonesia's daily emissions exceeded those of the entire US economy.

This was not new. An earlier wave of fires in 1997, during another strong El Niño, is estimated to have released up to 2.57 billion tonnes of carbon, about 40% of global fossil fuel emissions in an average year at the time.

Aerial footage released by Greenpeace International showed burned land stretching for kilometres around villages.

(The video originally embedded here is no longer available.)

What changed afterwards

The World Bank urged Indonesia to tackle the underlying causes of man-made fires, enforce existing laws and reform land policy. President Joko Widodo called for a halt to converting peatland to agriculture and for restoring damaged peat, including blocking canals so that water could rise again. Singapore used its Transboundary Haze Pollution Act, which allows fines on companies that contribute to haze, and named several firms.

Restoring peat is slow. Rewetting can make land less flammable within a few seasons, but the forest and the carbon it stored take generations to recover. Severe fire years since 2015 have shown that the risk returns whenever a dry El Niño year meets drained land.

Myths and misunderstandings

"It was just a bad wildfire season." These were largely human-set fires on drained peat, made worse by drought. Weather set the stage; land use lit the fuel.
"Only palm oil companies are to blame." Companies played a big role, but smallholders and land speculators also used fire, and much of the burning happened outside concessions.
"Nobody reported it." Regional media covered the haze intensively. What was missing, as Monbiot argued, was sustained attention in much of the Western press relative to the scale of the disaster.
"Once the flames are out, the danger is over." Peat can keep smouldering underground and reignite.

For readers who want to help, supporting organisations that protect and rewet peat forests, and choosing products with credible deforestation-free certification, are practical places to start. Monbiot's earlier book Poisoned Arrows (1989), about Indonesia's transmigration programme in West Papua, gives background on how land policy in the country has long shaped its forests.

Sources: Wikipedia: 2015 Southeast Asian haze; BenarNews, December 2015: World Bank puts cost of Indonesia's fires at $16.1 billion; George Monbiot, 30 October 2015 (published in the Guardian); Wikipedia: Peat swamp forest; Wikipedia: Tropical peat; Wikipedia: Bornean orangutan; Alex Pietrowski, Waking Times, 30 October 2015. Video footage: Greenpeace International and the Orangutan Tropical Peatland Project (OUTROP). Photo of orangutans: Antara Foto/Reuters.

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