Urbanization and wildfire exposure in the wildland-urban interface of the Himalayas

In recent decades, the Himalaya has experienced rapid urbanization and more wildfires. However, little is known about the long-term dynamics of the wildland urban interface (WUI) and fire patterns in the Himalayas. Also, it is unknown how fire patterns and exposures change over time in the rapidly urbanizing Himalayas. Here, we mapped the WUI and analyzed changes in fire patterns and exposure from 2000 to 2020 in the Himalayas. We found that urbanization has led to increases in wildfire exposure due to increases in both the WUI area and the population living in the WUI. Indeed, most population growth occurs in the WUI area. However, urbanization and wildfire patterns are different in different types of WUI. The intermix WUI area increased, but population density remained stable. In the interface WUI, population density increased, but the area remained stable. Fire is more extreme in the intermix WUI, with more fire counts, more burned area, higher spread rate, and longer duration of fires.