Spatiotemporal Analysis of Vegetation Fires and Carbon Monoxide Pollution in Indonesia

Vegetation fires in Indonesia, particularly in forests and peatlands, are major contributors to carbon monoxide (CO) pollution. El Niño events significantly exacerbate fire activity and emissions. An analysis of fire data from 2012 to December 2024 revealed an average of 21,271 fires per year, with peak activity typically in August, September, and October. 32.0% of the total recorded fires occurred in forests and 21.9% occurred in peatlands. El Niño periods, specifically 2015–2016, 2018–2019, and 2023–2024, were associated with over 400% more fires than non-El Niño years. A time series analysis using the seasonal Mann-Kendall test and Theil-Sen slope estimator confirmed a statistically significant downward trend in fire activity, with a median decline of approximately 502 fire counts per month, for the whole country. Seasonal analysis showed elevated fire risks during the late monsoon and post-monsoon months. Spatial analysis revealed a strong correlation between fire activity and CO emissions in forested regions, especially during El Niño years, with major fire and CO peaks in 2019 and 2023. Hotspots were observed in central Kalimantan, western Sulawesi, and southern Java. Peatlands also showed a notable, though weaker, spatial correlation between fires and CO concentrations. Overall, the results demonstrate that El Niño events markedly intensify fire dynamics and CO emissions, emphasizing the need for targeted fire management strategies in high-risk ecosystems such as tropical peatlands and forests.