Air quality trends of the Kathmandu Valley: A satellite, observation and modeling perspective

Air pollution in the Kathmandu Valley, Nepal, has increased by approximately 50–60% over the past two decades (2000–2015), with background pollution contributing an additional 20–25%. This finding was derived from satellite data (MODIS AOD) and supported by in-situ measurements and modeling. The study highlights the significant impact of background aerosol loading on local air quality, particularly during the dry season (November–June). Despite using advanced models like WRF-STEM and WRF-Chem, pollution levels were underestimated, suggesting gaps in current modeling approaches. Reduced visibility in Kathmandu is linked to this background pollution, emphasizing its role in urban air degradation.

Mahapatra, P. S., Puppala, S. P., Adhikary, B., Shrestha, K. L., Dawadi, D. P., Paudel, S. P., & Panday, A. K. (2019). Air quality trends of the Kathmandu Valley: A satellite, observation and modeling perspective. Atmospheric Environment, 201, 334–347. https://doi.org/10.1016/j.atmosenv.2018.12.043