Climate Change and El Nino Fueled Indonesia’s Worst Wildfires in a Decade

A strong El Nino and human-induced climate change fueled hot and dry weather over Indonesia, sparking the country’s worst wildfire season in a decade, a World Weather Attribution report shows.

Poor rainfall from June through the end of October left the ground bone-dry. Blazes linked to slash-and-burn agricultural practices became much harder to contain.

The severe weather cloaked local towns and neighboring countries such as Singapore and Malaysia in toxic smog. The smoke prompted schools to close, strained diplomatic ties, and crimped palm oil output.

“El Nino turned off the taps, but fossil fuel emissions turned up the heat,” said Friederike Otto, who works as an Imperial College London climate science professor and helped co-author the research released Friday. “Without rapidly transitioning away from fossil fuels and strengthened land-management protections, we will see more and much worse fire seasons like this in the future.”

El Nino drove the severe lack of rainfall, while human-induced climate change caused high temperatures. Human-induced warming made hot and dry conditions about three times more likely and more intense.

Climate change amplified hotter conditions from August to October, making seasonal heat about 1.6 C hotter and more likely to occur. Parts of Indonesia have also suffered decades of deforestation and peatland draining, which significantly increases fire risk.

The ongoing El Nino reduced Indonesia’s seasonal rainfall by about 50% this year. Together with higher temperatures, the country experienced record-breaking fire weather.

“Our analysis shows that climate change acts as a force multiplier during El Nino years,” said Theodore Keeping, who investigates wildfires and extreme weather at Imperial College London and served as the investigation’s primary author. “When a strong El Nino hits, global warming makes the resulting fire weather significantly hotter, drier, and harder to contain.”