Record-breaking air pollution caused by peatland fires in Sumatra has Malaysians and Singaporeans locked indoors — and Indonesia today plans to try an unconventional approach to tackling the flames.

The Indonesians will dump chemicals from aircraft high above smoldering palm plantations in hopes of changing the weather. The goal is to seed clouds and force them to rain their moisture out over the stubborn conflagrations, which were triggered by slash-and-burn forest-clearing by the palm oil industry.

Smoke from Sumatra fires

NASA GoddardSmoke from fires on Indonesia’s Sumatra island is polluting Singapore and Malaysia.

From the Straits Times:

Grist thanks its sponsors. Become one.

Two Casa 212 aircraft will be flown to the province’s capital, Pekanbaru, on Friday morning and a C-130 Hercules Air Force aircraft will also be readied for the effort.

Reader support helps sustain our work. Donate today to keep our climate news free. All donations DOUBLED!

Personnel, equipment and seed material to induce rain over clouds have already been sent to Pekanbaru on Thursday night, the agency in charge added.

Cloud seeding is an unusual approach to firefighting. But, then, this is no ordinary fire. From Agence France-Presse:

About 100 firefighters tackling the blazes were finding them difficult to extinguish as they were smouldering underground in carbon-rich peatland, mostly in oil palm plantations, he said.

Grist thanks its sponsors. Become one.

“It is extremely difficult to extinguish the fires that are burning under the surface of the peatland,” [Indonesian Forestry Ministry official Raffles Panjaitan] said.

He said the success of the cloud-seeding operation would depend on weather conditions.

“Hopefully there will be lots of clouds so that we can produce a lot of rain,” he added.

The worst-hit area was Bengkalis district, where 650 hectares of land was ablaze, he said, adding that 555 fires had been detected in Riau, up from 356 the previous month.

The smoke is fraying tempers in neighboring countries. From the BBC:

Pollution levels reached a new record high for a third day in a row in Singapore, as smoky haze from fires in Indonesia shrouded the city state.

The Pollutant Standards Index (PSI) hit 401 at 12:00 on Friday (04:00 GMT) – the highest in the country’s history.

The haze is also affecting Malaysia, with another 100 schools closed in the south of the country.

But Indonesia said the other affected countries share in the blame for the blazes. From CNN:

“The slash-and-burn technique being used is the cheapest land-clearing method and it is not only used by local farmers, but also employees of palm oil investors including Singaporean and Malaysian companies,” Hadi Daryanto, a senior official at Indonesia’s Forestry Ministry, told Indonesian media.

“We hope the governments of Malaysia and Singapore will tell their investors to adopt proper measures so we can solve this problem together.”

(Americans share in the blame, too. Palm oil is used in everything from lipstick to margarine and biofuel, and American imports from cleared Southeast Asian forests continue to skyrocket.)

Cloud seeding may sound futuristic, but it’s been practiced in the U.S. since the first half of the last century, including by water managers in California [PDF] eager to fill their reservoirs. It’s controversial because it can be unreliable and because it involves dumping chemicals, such as silver iodide, into the atmosphere. We’ll soon find out whether it’s enough to douse Indonesia’s unneighborly fire problem.