Indonesia tests dry ice to clear wildfire haze as smoke spreads to Singapore and Malaysia

A dry ice trial over Sumatra

Indonesian authorities plan to test an experimental method on Thursday, 15 October, when an aircraft will scatter pellets of dry ice, or solid carbon dioxide, over South Sumatra province, one of the regions worst hit by the haze. According to authorities, the trial involves 1.5 tons of dry ice. Unlike the cloud seeding used for weeks, which relies on compounds such as silver iodide to form ice crystals inside clouds, the dry ice is meant to break down haze in the lower atmosphere so that it can rise. Coordinating minister for political and security affairs Dudung Abdurachman said the approach would expand if the test works.

Dudung Abdurachman set out the next step in these words.

If this trial is successful, we will continue with other areas that are central to the haze, such as Central Kalimantan and its surroundings.

Fires, cloud seeding and the response

President Prabowo Subianto has called on agencies to step up efforts to extinguish the wildfires and reduce the impact of the smoke. Dozens of helicopters have been deployed, although poor visibility in the haze has at times disrupted those flights, and firefighters on the ground are still tackling blazes that are out of control. New cloud seeding operations are set for Central Kalimantan on Thursday and Friday, while local authorities in Malaysia, including in Kuala Lumpur and the city of Johor Bahru, have run their own cloud seeding operations. Indonesia's government says it has mobilized more than 60,000 personnel, and authorities have suspended the licences of 26 companies linked to the fires while opening investigations into others.

The fires have spread across peatland, where flames can keep burning underground and make them harder to fight. The independent forest monitoring platform Nusantara Atlas, cited by the BBC, puts the burned area at about 900,000 hectares. In Bangka Belitung province on Sumatra, almost 300 houses were destroyed and about 1,000 people left a village, according to local authorities cited by the Guardian. Civil society groups in Borneo have filed a class action demanding that the government address the annual wildfires.

Health and air quality

Indonesia's health ministry official Then Yuanti said 283,270 respiratory illness cases had been registered in fire-affected areas between 18 August and 13 October, a figure reported on Wednesday, 14 October. He gave no death toll. The national environment ministry recorded an ISPU air pollution reading above 1,200 in Palangka Raya, four times the 'hazardous' level of 300.

In Singapore, the environment agency said fine particle concentrations in the west were at a very high level on Wednesday, well above limits recommended by the World Health Organization. Bloomberg reported that the government will keep its options open on legal action against errant companies under its Transboundary Haze Pollution Act while it collects data on the haze. Air purifiers from brands including Xiaomi and Dyson sold out on retailers' websites. Diário de Notícias, citing the BBC, reported that some schools in Malaysia had closed, and East Timor ordered a three-day school closure from Thursday. SIC Notícias reported that Singapore ranked first on a list of the world's most polluted cities, and the FIA warned of possible restrictions around the Singapore Grand Prix but said the race would not be affected.

What comes next

Authorities warn that the fires could continue until November, when the El Niño phenomenon is expected to peak, while the civil society lawsuit against the government is pending.