Trends in Nighttime Fires in South/Southeast Asian Countries

Quantifying spatial variations and trends in nighttime fires is crucial for a comprehensive understanding of fire dynamics. Traditional fire monitoring typically focuses on daytime observations, but controlling nocturnal fires poses unique challenges due to reduced visibility. While several studies have focused on examining global and regional fire trends, very few studies have focused on nighttime fires, particularly in South/Southeast Asian (S/SEA) countries. In this study, we analyzed nighttime vegetation fires in S/SEA using VIIRS I-band (375 m) data, including a comparison with Sentinel-3A SLSTR data. The results suggested that similar to 28.25% of total fires occurred at night in SA, and 18.98% in SEA. In SA, a statistically significant (p =< 0.05) increase in nighttime fires was observed in Bangladesh. India showed a positive trend in nighttime fires, while Nepal, Pakistan, and Sri Lanka exhibited negative trends; however, these results were not statistically significant. In SEA, we detected statistically significant (p =< 0.05) decreases in nighttime fires in Cambodia, Indonesia, Malaysia, and Vietnam, with increases in Myanmar and the Philippines. Indonesia experienced the most substantial reduction in nighttime fires. Furthermore, VIIRS I-band detections were approximately 92-98 times higher than those of SLSTR-3A in S/SEA. Overall, our study offers valuable insights into nighttime fires and trends in S/SEA countries, which are useful for fire prevention, mitigation and management in the region.