Dr. Hemraj Bhattarai is a Research Assistant Professor specializing in Earth and Atmospheric Sciences. His research investigates the complex interactions between land use, climate change, and emissions, and their impacts on air quality, wildfires, and human health. Utilizing a multi-faceted approach that combines ground-based observations, satellite data, 3-D chemical Earth system models like CESM and GEOS-Chem, and machine learning techniques, he works across local to global scales. Dr. Bhattarai holds a Ph.D. from The Chinese University of Hong Kong and has authored numerous high-impact publications. His current work focuses on analyzing toxic air pollutants and assessing the associated health burden, establishing him as an emerging leader in environmental science.

Research Themes under ENVR

• Air and Health

Research Areas

• Atmospheric chemistry and physics
• Air pollution and health
• Observations and modeling

Research Interests

• PM2.5 and ozone chemistry
• Toxic pollutants (e.g., PAHs)
• Wildfires and climate change

Publications

Representative Publications

• Bhattarai, H., Tai, A. P. K., Val Martin, M., & Yung, D. H. Y. (2024a). Impacts of changes in climate, land use, and emissions on global ozone air quality by mid-21st century following selected Shared Socioeconomic Pathways. Sci. Total Environ., 906, 167759. https://doi.org/10.1016/j.scitotenv.2023.167759
• Bhattarai, H., Tai, A. P. K., Val Martin, M., & Yung, D. H. Y. (2024b). Responses of fine particulate matter (PM2.5) air quality to future climate, land use, and emission changes: Insights from modeling across shared socioeconomic pathways. Sci. Total Environ., 948, 174611. https://doi.org/10.1016/j.scitotenv.2024.174611
• Bhattarai, H., Wu, G., Zheng, X., Zhu, H., Gao, S., Zhang, Y.-L., Widory, D., Ram, K., Chen, X., Wan, X., Pei, Q., Pan, Y., Kang, S., & Cong, Z. (2023). Wildfire-Derived Nitrogen Aerosols Threaten the Fragile Ecosystem in Himalayas and Tibetan Plateau. Environ. Sci. Technol., 57(25), 9243–9251. https://doi.org/10.1021/acs.est.3c01541
• Bhattarai, H., Tripathee, L., Kang, S., Chen, P., Sharma, C. M., Ram, K., Guo, J., & Rupakheti, M. (2022). Nitrogenous and carbonaceous aerosols in PM(2.5) and TSP during pre-monsoon: Characteristics and sources in the highly polluted mountain valley. J. Environ. Sci., 115, 10–24. https://doi.org/10.1016/j.jes.2021.06.018
• Bhattarai, H., Tripathee, L., Kang, S., Sharma, C. M., Chen, P., Guo, J., & Ghimire, P. S. (2021). Concentration, sources and wet deposition of dissolved nitrogen and organic carbon in the Northern Indo-Gangetic Plain during monsoon. J. Environ. Sci., 102, 37–52. https://doi.org/10.1016/j.jes.2020.09.011
• Pei, Q., Wan, X., Widory, D., Ram, K., Adhikary, B., Wu, G., Diao, X., Bhattarai, H., Zhang, Y.-L., Loewen, M., & Cong, Z. (2024). Nitrogen aerosols in New Delhi, India: Speciation, formation, and sources. Atmos. Res., 304, 107343. https://doi.org/10.1016/j.atmosres.2024.107343
• Bhattarai, H., Saikawa, E., Wan, X., Zhu, H., Ram, K., Gao, S., Kang, S., Zhang, Q., Zhang, Y., Wu, G., Wang, X., Kawamura, K., Fu, P., & Cong, Z. (2019). Levoglucosan as a tracer of biomass burning: Recent progress and perspectives. Atmos. Res., 220, 20–33. https://doi.org/10.1016/j.atmosres.2019.01.004
• Bhattarai, H., Zhang, Y.-L., Pavuluri, C. M., Wan, X., Wu, G., Li, P., Cao, F., Zhang, W., Wang, Y., Kang, S., Ram, K., Kawamura, K., Ji, Z., Widory, D., & Cong, Z. (2019). Nitrogen Speciation and Isotopic Composition of Aerosols Collected at Himalayan Forest (3326 m a.s.l.): Seasonality, Sources, and Implications. Environ. Sci. Technol., 53(21), 12247–12256. https://doi.org/10.1021/acs.est.9b03999
• Pokharel, M., Guang, J., Liu, B., Kang, S. C., Ma, Y. M., Holben, B. N., Xia, X. A., Xin, J. Y., Ram, K., Rupakheti, D., Wan, X., Wu, G. M., Bhattarai, H., Zhao, C. F., & Cong, Z. Y. (2019). Aerosol Properties Over Tibetan Plateau From a Decade of AERONET Measurements: Baseline, Types, and Influencing Factors. J. Geophys. Res.: Atmos., 124(23), 13357–13374. https://doi.org/10.1029/2019jd031293
• Wan, X., Kawamura, K., Ram, K., Kang, S., Loewen, M., Gao, S., Wu, G., Fu, P., Zhang, Y., Bhattarai, H., & Cong, Z. (2019). Aromatic acids as biomass-burning tracers in atmospheric aerosols and ice cores: A review. Environ. Pollut., 247, 216–228. https://doi.org/10.1016/j.envpol.2019.01.028