South-east Asia’s worst haze episodes explained

In September, the International Union for Conservation of Nature warned that fires were burning in habitats containing 52 per cent of Borneo’s orangutan population.

Indonesia had rescued 232 wild animals as at Oct 8, including 76 proboscis monkeys and 71 orang utans in Borneo.

The persistent fires in Kalimantan and Sumatra have sparked unrest, with protests erupting across parts of Indonesia as frustration swelled over the government’s handling of the blazes. Demonstrators demanded stronger firefighting efforts, tougher action against companies responsible for the blazes and greater protection for affected communities.

Singapore has served legal notices under its Transboundary Haze Pollution Act to 10 companies, asking them to provide more information on fire prevention and suppression strategies. 

2015

The haze episode in 2015 was declared the most severe on record.

The inferno was amplified by a strong “Godzilla” El Nino. A Harvard University study estimated that the 2015 crisis caused 100,000 premature deaths across Indonesia, Malaysia and Singapore.

According to the World Bank, Indonesia’s forest fires that year cost 221 trillion rupiah (S$15.6 billion), more than twice the amount spent on reconstruction efforts after the 2004 Aceh tsunami.

In Singapore, the economic cost of the haze was estimated at $1.83 billion, or 0.45% of the country’s gross domestic product, according to a 2021 report by researchers from Nanyang Technological University’s economics division.

Schools in Singapore closed on Sept 25 when the PSI exceeded 300, hitting the hazardous range.

The Indonesian forest fires released more carbon than the entire European Union, according to a 2016 study published in Scientific Reports. In September and October 2015, the blazes spewed around 11.3 million tonnes of planet-warming carbon emissions daily.

1997

The fires lasted four months from July to November and cost Singapore an estimated US$163 million (S$208 million).

This was compounded by the Asian financial crisis that year.

On Sept 18, the PSI hit an all-time high of 226 at 10pm, with visibility plummeting to a few hundred metres in the worst-hit western region.

The haze crisis cost the region – including Brunei, Indonesia, Malaysia, the Philippines, Singapore and Thailand – more than US$9 billion in economic, social and environmental losses, according to the ASEAN website.

The persistent burning released an estimated one billion to two billion tonnes of carbon into the atmosphere.

Across the region, more than 40,000 people were hospitalised for respiratory and other haze-related ailments. Flights were grounded because of visibility concerns, leading to declines in tourism.

The haze also affected wildlife and pets, with dogs sneezing and songbirds going silent.

The 1997 crisis prompted the region to sign the legally binding ASEAN Agreement on Transboundary Haze Pollution in 2002. It obligates member states to take legislative and administrative measures to prevent and control land and forest fires.

1982

The 1982 to 1983 episode was the first documented large fire and smoke episode in the second half of the 20th century in Indonesia, according to the UN Food and Agriculture Organization.

The vast fires on Borneo – dubbed the Great Fire of Borneo – were sparked by extreme drought and extensive slash-and-burn land clearing, and it has been estimated that more than five million ha of land was burned across the island, which includes East Kalimantan.

Many complained of eye irritation, and Singapore’s then anti-pollution unit detected 300 micrograms of fine suspended particles in the air.

The PSI was not used in Singapore until the 1990s.

A 2020 paper published in the Journal of International Studies found that Singapore did not consider haze pollution a health risk until 1994, when the PSI system was adopted alongside health indicators.