Palangkaraya registers AQI 780, becoming Indonesia's most polluted city.

Palangkaraya, the capital of Central Kalimantan on the island of Borneo, recorded an air‑quality index of 780 on Tuesday, making it the most polluted city in Indonesia’s archipelago. The reading, taken by the provincial environmental agency, reflects the intensifying haze generated by wildfires that have been raging across the island’s peatlands for more than a week.

Palangkaraya, home to roughly 318,000 residents according to a mid‑2025 estimate, occupies a strategic position between the Kahayan and Sabangau rivers. Although the city covers an area four times larger than Jakarta, much of that land remains forested, especially in its northern districts of Rakumpit and Bukit Batu, which include several protected conservation zones. As the administrative, economic and educational hub of Central Kalimantan, the city’s rapid development since its founding in 1957 has been juxtaposed with recurring environmental challenges, most notably haze, forest fires and seasonal flooding.

The current haze stems primarily from peat‑soil fires ignited by illegal slash‑and‑burn clearing practices in the region’s extensive peatlands. These soils, when dry, release large quantities of particulate matter and carbon dioxide, creating a thick, persistent smog that spreads far beyond the immediate fire zone. Indonesia’s Ministry of Environment and Forestry attributes the surge to a combination of prolonged dry conditions linked to an El Niño‑driven climate anomaly and the difficulty of accessing remote fire sites. Local authorities have deployed ground crews and water‑bombing aircraft, while satellite‑based monitoring is being used to map hotspots. However, non‑governmental organisations such as Greenpeace Indonesia argue that enforcement remains weak, citing inadequate penalties for land‑clearing violations and insufficient coordination among provincial agencies.

The haze is not confined to Central Kalimantan. Prevailing winds have carried pollutants westward toward the Malaysian states of Sarawak and Sabah, and further to Singapore, prompting health advisories, school closures and temporary flight suspensions. The World Health Organization’s air‑quality guidelines classify an AQI above 300 as “hazardous,” a level now regularly recorded in several Indonesian towns. Economically, the haze threatens tourism, disrupts supply chains for agricultural products, and imposes additional healthcare costs across the affected regions.

Indonesia’s government has responded with a multi‑pronged strategy that includes a 2023‑2025 “Zero‑Burn” policy, increased funding for fire‑fighting equipment, and bilateral talks with neighboring ASEAN members to share resources and data. The Ministry of Foreign Affairs has emphasized Indonesia’s commitment to “regional responsibility” and urged neighboring countries to support joint monitoring initiatives rather than impose punitive measures. Conversely, Malaysia’s Ministry of Environment and Water has called for stricter accountability and faster implementation of Indonesia’s fire‑prevention laws, while Singapore’s National Environment Agency has offered technical assistance for satellite tracking. The differing positions underscore a broader diplomatic tension: Indonesia seeks to balance economic development and sovereign land‑use decisions with regional pressure to curb transboundary pollution.

The situation matters for the wider Southeast Asian region, including Taiwan, because the haze can affect air travel routes that pass over the South China Sea, potentially leading to flight diversions and delays that ripple through international supply chains. Moreover, the persistent burning of peat contributes to global greenhouse‑gas emissions, intersecting with Taiwan’s climate‑change mitigation goals and its participation in regional environmental forums. The episode also highlights the importance of collaborative disaster‑response mechanisms and the need for stronger enforcement of land‑use regulations to protect both public health and economic stability across neighboring economies.