Seasonal Characteristics, Sources and Pollution Pathways of PM_(10) at High Altitudes Himalayas of India

Nikki Choudhary ； Priyanka Srivastava ； Monami Dutta ； Sauryadeep Mukherjee ； Akansha Rai ； Jagdish Chandra Kuniyal ； Renu Lata ； Abhijit Chatterjee ； Manish Naja ； Narayanasamy Vijayan ； Tuhin Kumar Mandal ； Sudhir Kumar Sharma

《Aerosol and Air Quality Research》 22卷7期 (2022/07) Pp. 1-26+ap1-22-004

https://doi.org/10.4209/aaqr.220092

摘要

The present study represents the annual and seasonal concentration of PM_(10) over different sites (Darjeeling, Nainital, Mohal-Kullu) across the Himalayan region of India from July 2018 to December 2019. The collected PM_(10) samples were analyzed for carbonaceous aerosols [organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC), primary organic carbon (POC), secondary organic carbon (SOC)] and major trace elements to inspect their possible sources. The annual average concentrations of PM_(10) over Mohal-Kullu, Nainital, and Darjeeling were recorded as 57 ± 32 μg m^(-3), 65 ± 41 μg m^(-3), and 54 ± 17 μg m^(-3), respectively. The high OC/EC ratio and significant correlation of OC with EC and WSOC with OC indicated a significant effect of biomass burning aerosols over the study sites. Principal component analysis/absolute principal component score (PCA/APCS) resolved four major sources: crustal/soil dust (26.6%), biomass burning/fossil fuel combustion (28%), vehicular emissions (28%), and industrial emissions/coal combustion (17%). Identification of the source region using the potential source contribution function (PSCF) and concentration weighted trajectories (CWT) showed that PM_(10) was mainly transported from the northwestern part of India (Haryana, Punjab), the northeastern region of Pakistan, the Thar Desert, and Indo-Gangetic Plain (IGP), which contributed to dust-related aerosols over the Himalayan region of India.

關鍵字

Aerosol ； Principal component analysis ； Carbonaceous aerosols ； Primary organic carbon ； Himalayas