Crippa Research on Catastrophic 2015 Indonesian Wildfires Published in ERL

Author: Allison Preston

Paola Crippa

Professor Paola Crippa’s research on the 2015 Indonesian wildfires was published in the academic journal Environmental Research Letters (ERL). The Civil and Environmental Engineering and Earth Sciences Melchor Assistant Professor analyzed air quality in Equatorial Asia during one of the largest, and most intense wildfires in the region. She and her team performed a unique model-based study on the catastrophic occurrence.

The event was the largest wildfire in the past 30 years in Indonesia. The fires were primarily located in the Indonesian Borneo region where deforestation had been occurring. Expansion of agricultural practices has been causing widespread deforestation and extensive drainage of peatlands, drying out vegetation and soils. These practices have made the landscape particularly prone to fire. In 2015, dry weather associated with strong El-Niño conditions only exacerbated the problem.

At the time, Prof. Crippa had been awarded a L'Oréal-UNESCO for Women in Science Fellowship to investigate wildfires issues in Southeast Asia. Months later the fires in the Indonesian Borneo began to spread out of control. Hazardous pollutants, including particulate matter (PM), carbon monoxide (CO) and smoke spread throughout Indonesia, Sumatra, and the highly populated Malaysian Peninsula. As a result, the hazardous air quality led to a widespread haze crisis. Six Indonesian provinces declared a state of emergency, residents fled from their homes, and schools were closed across the entire region. The Guardian called the disaster a “crime against humanity” as people suffocated from the poor air quality.

Chart contrasting air quality in Indonesia with wildfires versus no wildfires

“I immediately decided to focus my research on that particular event hoping to demonstrate by using the most advanced air quality models that those extreme pollution episodes were impacting a large fraction of the population living there,” said Prof. Crippa.

Providing accurate pollution estimates and quantifying the number of people exposed to the pollutants from the wildfires was a major challenge for Crippa and her team. Their study integrates new observations from 49 monitoring stations across Peninsular Malaysia and Malaysian Borneo during the haze event with high-resolution air quality model simulations.

Map showing PM10 an CO observations from 49 monitoring stations across Peninsular Malaysia and Malaysian Borneo

Prof. Crippa’s studies estimate roughly 70 million people in Malaysia and neighboring countries were affected, resulting in roughly 10,800 deaths in densely populated regions of Equatorial Asia. The team found more than 60 percent of the population living in the Greater Klang Valley and more than 40 percent of Malaysia citizens had been exposed to harmful concentrations of PM and CO.

So was this an isolated event, or can the region expect similar occurrences in the coming years?

“The shift in climate is already making these wildfires more common,” Prof. Crippa said. “They are increasing in frequency and intensity.”

This study shows the importance of deploying instrumentation monitoring air quality and of implementing strategies to prevent the occurrences of similar extreme events.

Pollutant standards index graphic over Indonesia

“Land use change in Equatorial Asia is a very complex problem from a social, economic and environmental point of view,” says Crippa. “It is important to agree on solutions that would allow a reduction of outdoor pollution levels to the recommendations by the World Health Organization.”

Prof. Crippa’s team is currently working on improving their estimates by seeking additional official statistics on the exposure. While the challenges for implementing prevention strategies are considerable, a coordinated effort from multiple countries in the region will allow to control and limit future wildfires.

“Air pollution is not just a local or national phenomenon, it is a regional problem and affects multiple countries. Dialogue among nations is necessary and in the interest of everybody to prevent premature deaths, especially of the most vulnerable portions of the population.”

For the full report, visit the Environmental Research Letters website.