ABSTRACT
The forest fire regime has been altering due to changing climatic patterns and the increasing human footprint. The present study examined changes in the forest fire regime (e.g., spatio-temporal distribution, trend, peak fire time, and size of burn spots) and its connections with regional climatic conditions over Himalaya (India, Nepal, and Bhutan) in the last two decades. A moderate resolution imaging spectroradiometer (MODIS)–derived MCD64A1 burn area dataset was used to extract the fire information (i.e., burn area and date). For the climatic variables (i.e., maximum temperature, minimum temperature, precipitation, and Palmer Drought Severity Index), data from TerraClimate were used to quantify their trend and variability and their connections with changing forest fire regimes. Over the last two decades, the highest annual average burn area was 3156 (σ = 1958) km2 in Eastern Himalaya (including Bhutan). We observed an increasing trend in burn area (837.82km2 year−1) in the first decade (2001–2010) and a decreasing trend (–297.22km2 year−1) in the last decade (2011–2020), particularly over Eastern Himalaya (257.82km2 year−1). The peak fire has a wide variation over the Himalayas; mainly peak fire time is concentrated between March and May. In the last decade, the average peak fire time was delayed by 7 to 24 days from the first decade. The size (km2) of the fire spots varies from Western to Eastern Himalaya. The largest fire spot was found over Nepal (1.91km2), followed by Western Himalaya (1.50km2) and Eastern Himalaya (1.12km2). The burn area trend and changes in the size of fire spots exhibited a correspondence with decadal scale trend of climatic components (specifically, temperatures and precipitation). The annual burn area climatic variables showed a moderate to weak association (r = 0.6 to −0.47); the weak relation could be explained by other affecting factors.
