Emission study to close data gaps


Emission is a major determinant of air quality, and improving quantification and characterization of emission sources in the Hindu Kush Himalayan (HKH) region is one of the main goals of the Atmosphere Initiative of the International Centre for Integrated Mountain Development (ICIMOD). 

Therefore, in collaboration with scientists funded by the US National Science Foundation (NSF), ICIMOD organized a first-of-its-kind field campaign to characterize gaseous and particle-phase air pollutants emitted from various combustion sources across Nepal.  Five research groups from the US (Universities of Montana, Iowa, Emory, Virginia, and Drexel) were instrumental in raising over USD 1 million from the NSF to conduct the field campaign. The Nepali company MinErgy was hired by ICIMOD as a local partner to assist and ensure smooth functioning of the study.

Measuring cookstove emissions
Photo credit: Subasana Shrestha/ICIMOD

While the broader study includes activities such as the evaluation of existing emission inventories and the collection of activity data, the focus of the field campaign was on ambient measurements, especially the improvement of emission factors which have been key sources of weakness in the emissions quantification in the HKH region. The study directly sampled emissions from individual sources such as brick kilns, cooking stoves, agricultural groundwater pumps, motor vehicles, and generator sets using state-of-the-art custom-built instruments that were temporarily imported into Nepal for the campaign.

The researchers measured emissions from cookstoves, vehicles, diesel generators, diesel pumps, various open fires, and brick kilns. In order to get a complete overview of cooking emissions of the possible stove/fuel combinations, the team produced the sampling matrix integrating different types of stoves, single-pot traditional mud stove, dual-pot, gas stove, and also considered all of the possible stove/fuel combinations.

When the earthquake struck Nepal on 25 April, the team was on the Narayanghat Mugling Road on its way back to Kathmandu after a week of sampling Tarai sources.  While the campaign was cut short, the data collected is currently being analyzed and prepared for publication in peer-reviewed papers. 

The study is expected to provide more accurate data about emission factors for specific sources in the HKH region, such as the grams of carbon monoxide emitted per liter of diesel fuel burned by overloaded freight trucks climbing uphill, or the chemical speciation profiles of plastic burning – the fractions of particulate matter and volatile organic gases that enter the atmosphere as carcinogenic compounds. The field measurements will be used to construct a detailed inventory of air pollutant emissions that can be used immediately to guide mitigation strategies in Nepal and the region.