Pre-monsoon air quality over Lumbini, a world heritage site along the Himalayan foothills

Lumbini, a UNESCO World Heritage Site and the birthplace of Lord Buddha, faces severe air pollution challenges that pose risks to public health and heritage preservation. A study conducted during the pre-monsoon season (April–June 2013) revealed alarmingly high levels of key pollutants—PM1, PM2.5, PM10, black carbon (BC), ozone (O₃), and carbon monoxide (CO)—comparable to other heavily polluted South Asian sites. Notably, coarse-mode particulate matter dominated, and emissions from both residential and transportation sectors significantly contributed to pollution, with fossil fuel combustion accounting for over half of BC concentrations. The study also identified agro-residue burning and regional forest fires, exacerbated by meteorological conditions, as primary drivers of severe air quality episodes. While a regional chemical transport model (WRF-STEM) underestimated observed pollutant levels, it highlighted the Ganges Valley as a major source of CO. The findings underscore an urgent need for long-term air quality monitoring in Lumbini to mitigate health risks and protect cultural heritage.

Rupakheti, D., Adhikary, B., Praveen, P. S., Rupakheti, M., Kang, S., Mahata, K. S., Naja, M., Zhang, Q., Panday, A. K., & Lawrence, M. G. (2017). Pre-monsoon air quality over Lumbini, a world heritage site along the Himalayan foothills. Atmospheric Chemistry and Physics, 17(18), 11041–11063. https://doi.org/10.5194/acp-17-11041-2017