Glaciers in the Himalayas and Andes are the main water sources for over 1.5 billion people in South and East Asia and 77 million people in South America. Due to climate change and deposition of short-lived climate pollutants like black carbon (BC), these glaciers are melting at unprecedented rates. This melting has implications for freshwater sources, extreme flooding, water conflicts, and food security for much of South Asia and South America.
Black Carbon Emissions from Open Burning
Open burning is the single largest source of BC emissions globally, approximately 2700 Gg or 36% of BC emissions, with agricultural fires comprising 10-20% of all fires. Biomass burning will likely cause a 0.4oC temperature increase in the next 20 years of global climate change. Short-lived climate pollutants (SLCPs), including methane (CH4), BC, and tropospheric ozone (O3), have atmospheric lifetimes ranging from a few days to several weeks and as much as 12 years for CH4, which means their abatement can have an almost immediate and lasting positive impact on climate change and air quality.
Burning of agricultural fields and wildland fires are sources of black carbon deposition on these glaciers. For example, fire is commonly used across South Asia to support agricultural and pasture management, specifically to remove excess crop residue and other agricultural waste, but these fires can spread into wildland areas during the dry season. These wildland fires in Nepal tend to occur between December and May, with a peak in April. Agricultural burning in Nepal occurs in March through June, with a large amount of burning also along the border in India at the same time. Burning is widespread throughout southern and central Nepal in the Teria and Hill Districts, with the same rice-wheat cropping system as the Punjab regions and much of the Indo-Gangetic Plain.
There is also an opportunity for the fire science and wildland fire management community around the world to assist and advocate for climate-smart agriculture techniques that reduce and/or eliminate unnecessary open burning in agroecosystems. For example, integrating prescribed burning of neighboring agroecosystems with wildland fire management, especially given increased wildland fire risk in a warming climate and severe air pollution events caused by prescribed burning, like occurred in New Delhi, India in Fall 2016 . Conservation International has begun to develop community-based and community-guided systems for doing this via their Firecast system. Future air pollution management of wildland fires will have to include planning of prescribed fire in agroecosystems.