Prolonged drought conditions have resulted in frequent and severe fire events across the country.

These fire occurrences have a colossal negative impact on human health and well-being, economic assets, biodiversity, atmosphere, and climate, particularly in the post-2000 era.

For instance, in Marchand April 2021, the quality of air in Kathmandu was unhealthy and occasionally hazardous due to fire events in different parts of Nepal.

It is an arduous task to predict fire occurrences with its lead time (about 1-2 months), which can help in taking appropriate, timely action to minimise the loss incurred due to forest fire. Scientists have been continuously working on fire prediction mechanisms by using the latest climate models. However, their efforts have not yielded much by way of results.

Recently, a research led by Kalpana Hamal, Shankar Sharma, and a team collaborated with the Central Department of Hydrology and Meteorology, Tribhuvan University, and studied the inter-annual variability of spring fire focusing on southern Nepal from 2001 to 2020. They found the influence of El Niño Southern Oscillation (ENSO) on fire variability. ENSO is one of the natural factors, and oscillation between its warm period (El Niño) and cold period (La Niña) can significantly cause fire occurrences.

Interestingly, the research found that high spring fire occurrences in southern Nepal during the El Niño years, which created dry and warm conditions, were associated with suppressed westerly moisture transport and abnormal moisture divergence.

Reduced spring precipitation and an extremely high temperature enhance evapotranspiration from vegetation and provide more combustible fuels.

The variations in surface and atmospheric conditions during the El Niño event favours fire events and its spread in Nepal.

A version of this article appears in the print on May 05, 2022, of The Himalayan Times