The 2026 fire season in Indonesia was one of the worst on record, producing thick smoke that spread across Southeast Asia. Understanding why these fires were so intense helps us see how climate, weather patterns and human activity can affect health and the environment.

A very strong El Niño dominated the weather from July 2026, causing extremely low rainfall across the archipelago. According to a World Weather Attribution report, human‑induced climate change added about 1.6 °C of extra heat during the fire season, making the dry conditions even hotter. Pramudhian Firdaus, a wildfire researcher at Melbourne University, noted that September 2026 was Indonesia’s fifth‑driest September since 1991, with rainfall below normal across 84 % of the country.

Pramudhian Firdaus said that decades of deforestation and peatland drainage have created landscapes that are extremely vulnerable to ignition. These land‑use changes have dramatically altered Indonesian forests over the last 30 years.

Data from the independent geo‑monitoring platform Nusantara Atlas show that almost 2.88 million hectares burned from January to October 2026, with nearly 1 million hectares added in October alone. The fire‑damaged area in the first three quarters was 35 % higher than in the same period of 2019, the last year of a strong “super‑El Niño”.

In short, the 2026 Indonesian wildfires were unusually severe because human‑driven heat, a strong El Niño, and decades of deforestation and peatland drainage combined to create a highly flammable landscape. This shows how climate, weather and land use together can drive extreme fire events.