Anthropogenic fine aerosols dominate over the Pune region, Southwest India

R D Gawhane,D C Meshram,P D Safai,P S P Rao,Krishnakant Budhavant

doi:10.1007/s00703-018-0653-y

Abstract

The major water-soluble ions, organic carbon (OC), elemental carbon (EC) and mass concentration of fine- (PM2.5) and coarse-mode (PM10–2.5) aerosols were measured at Pune during January–December 2016. The mass closure approach was used by comparing the sum of the masses of the individual chemical species to the gravimetric PM obtained by weighting the filter samples. The 1 year mean total mass concentration of fine and coarse mode was 40 µgm−3 (64%) and 23 µg m−3 (36%), respectively. The PM2.5/PM10 ratio was 0.64 ± 0.9 indicating an abundance of fine-mode particles over Pune during the study period. A principal component analysis identified three components, where the one with highest explanatory power (59%) displayed clear impact of anthropogenic sources on the measured mass concentration of a majority of the compounds. The strong linear relationships between EC, OC, nss-SO42− and nss-K+ suggest a predominance of a common primary source, with a contribution from biofuel as well as biomass burning sources. Keeping the strong correlation and sources of individual chemical species as the base, it was noticed that (1) major contributors to fine- and coarse-mode particles over the Pune regions are carbonaceous aerosols and secondary inorganic aerosols (non-sea-salt SO42−, NO3−, and NH4+), (2) anthropogenic aerosols contribute mostly to the fine-mode, and (3) meteorological parameters play an important role in controlling levels of fine- and coarse-mode particles. Taken together, the study clearly indicates the dominance of anthropogenic sources during the entire year with more significance in the winter season.

Highlights

The rapid growth in emerging economies over the last decades has led to dangerous levels of air pollution throughout Asia (Grandey and Cheng 2016; Cohen et al 2017; Lelieveld et al 2018)
The present paper describes yearround data sets on fine- and coarse-mode aerosol mass with major organic and inorganic chemical constituents collected in Pune, India
The chemical components were divided into four classes: carbonaceous aerosols (EC + OM), secondary inorganic aerosols (SIA), sea salt and dust

Summary

Introduction

The rapid growth in emerging economies over the last decades has led to dangerous levels of air pollution throughout Asia (Grandey and Cheng 2016; Cohen et al 2017; Lelieveld et al 2018). Air pollution levels in many South Asian cities are above the World Health Organization guideline values (WHO 2018). The human population of South Asia is about one-fifth of the world population (Im et al 2017). Chemistry (ACES), Stockholm University, 10691 Stockholm, Sweden 3 Department of Geology, Savitribai Phule Pune University, Pune 411007, India components have multiple secondary effects, including surface dimming (affecting agricultural crop yields), glacier melt and shifts of the storm frequency and the monsoon system (Haywood and Boucher 2000; Bollasina et al 2011; Atkinson et al 2014; Boucher et al 2013; Cohen et al 2017; WHO 2018)

Methods

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Discussion

Conclusion