Firefighters spray water to extinguish a forest fire in Kampar, Riau province, Indonesia, Sept 23, 2019. Indonesia's forest fires are an annual problem that strains relations with neighboring countries. The smoke from the fires blanketed parts of Indonesia, Singapore, Malaysia and southern Thailand in a noxious haze. (PHOTO / AP)

Malaysian environmental activist Heng Kiah Chun was in primary school when one of the most severe transboundary haze events happened in 1997. He recalled classes were suspended and flights were delayed when severe air pollution blanketed Kuala Lumpur.

Heng would later learn the smog polluting Malaysia's capital was caused by Indonesian forest fires. Slash-and-burn practices combined with an intense dry spell produced smoke that darkened skies and lungs across Southeast Asia.

Others shared Greenpeace's sentiment but also acknowledged that weak law enforcement and ASEAN's non-interference policy make it difficult to resolve the problem

Heng, now a regional campaign strategist for the NGO Greenpeace, is urging the Association of Southeast Asian Nations "to act decisively" as the impending El Nino is set to enhance the likelihood of transboundary haze this year.

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Plantation and logging companies, which continue to use fire to clear land, must be held accountable for the forest fires that lead to haze, he said.

"Enacting a domestic Transboundary Haze Act is still necessary to act as a deterrent, especially as there are bad apples in the industry. It can provide legal grounds for each country to institutionalize checks and balances to ensure their own companies operate responsibly," Heng said, adding that action-oriented accountability and greater transparency can strengthen ASEAN's strategy in the long run.

Heng made this call ahead of ASEAN's August meeting on transboundary haze pollution. Others shared Greenpeace's sentiment but also acknowledged that weak law enforcement and ASEAN's non-interference policy make it difficult to resolve the problem.

Whether transboundary haze will be a problem or not depends on how government authorities and agricultural companies manage burning as a land-clearance practice. 

Koh Tieh Yong, Weather and Climate Scientist 

Koh Tieh Yong, weather and climate scientist in Singapore, said drier and hence hotter conditions in the region will make peatland forest fires harder to control once started.

"Whether transboundary haze will be a problem or not depends on how government authorities and agricultural companies manage burning as a land-clearance practice," he said.

The root cause

Uli Arta Siagian, manager of forestry and plantation campaigns for the nonprofit Indonesian Forum for Environment, said the Indonesian government and ASEAN should look into the root cause of forest fires — the indiscriminate approval of licenses and lack of regulation over plantation projects.

The main problem of cross-border smog stems from the fact that multinational corporations invest in countries with weak law enforcement or weak civil society, said Noppachai Fongissara, assistant professor at the School of Social Sciences in Chiang Rai Rajabhat University in Thailand.

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Noppachai, who has authored papers on transboundary haze, said through the 2002 signing of the ASEAN Agreement on Transboundary Haze Pollution, ASEAN already has a mechanism to regulate transboundary haze. As AATHP signatories, ASEAN members need to cooperate and implement measures that can prevent, monitor and mitigate transboundary haze pollution.

In this Sept 18, 2019, file photo, smoke billows from forest fires in Kahayan Hilir, Central Kalimantan, Indonesia. (PHOTO / AP)

"Unfortunately, this approach is hampered by ASEAN customs and principles … The problem of cross-border pollution has been going on for decades and no progress has been made to address it," he said.

The ASEAN Specialized Meteorological Centre said on May 29 that the dry season has started in the southern ASEAN region, noting that "persistent drier weather" has been observed in Brunei, Indonesia, Malaysia, Singapore and southern Thailand. There is a "high likelihood" that El Nino conditions will develop in the coming months, with the dry season intensifying and extending into October.

ASEAN environment ministers, who met in Singapore on June 8, took this forecast into account. In a statement released after the meeting, the ministers said that because of the prolonged and intense dry season, "the risk of elevated hot spot activities and transboundary smoke haze occurrence was the highest since 2019".

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They agreed to expedite the establishment of the ASEAN Coordinating Centre for Transboundary Haze Pollution Control in Indonesia to facilitate the faster and more effective implementation of all aspects of the AATHP.

Noppachai, the Thai expert, said while it is "theoretically possible" to pass a regional law specifically targeting transboundary haze, that could only be done if there is pan-ASEAN consensus and willingness to adopt binding legal measures.

"This could be a complex process, considering the diverse interests and priorities of (ASEAN) member countries."

Leonardus Jegho in Jakarta contributed to this story.