Home > Research > Publications & Outputs > Enhanced aerosol particle growth sustained by h...

Electronic data

  • 32946_1_art_file_308548_qkmbpw

    Accepted author manuscript, 211 KB, PDF document

    Embargo ends: 25/07/21

Links

Text available via DOI:

View graph of relations

Enhanced aerosol particle growth sustained by high continental chlorine emission in India

Research output: Contribution to journalJournal articlepeer-review

Published
  • S.S. Gunthe
  • P. Liu
  • U. Panda
  • S.S. Raj
  • A. Sharma
  • E. Darbyshire
  • E. Reyes-Villegas
  • J. Allan
  • X. Wang
  • S. Song
  • M.L. Pöhlker
  • L. Shi
  • Y. Wang
  • S.M. Kommula
  • T. Liu
  • R. Ravikrishna
  • G. McFiggans
  • L.J. Mickley
  • S.T. Martin
  • U. Pöschl
  • M.O. Andreae
  • H. Coe
Close
<mark>Journal publication date</mark>25/01/2021
<mark>Journal</mark>Nature Geoscience
Volume14
Number of pages8
Pages (from-to)77-84
Publication StatusPublished
<mark>Original language</mark>English

Abstract

Many cities in India experience severe deterioration of air quality in winter. Particulate matter is a key atmospheric pollutant that impacts millions of people. In particular, the high mass concentration of particulate matter reduces visibility, which has severely damaged the economy and endangered human lives. But the underlying chemical mechanisms and physical processes responsible for initiating haze and fog formation remain poorly understood. Here we present the measurement results of chemical composition of particulate matter in Delhi and Chennai. We find persistently high chloride in Delhi and episodically high chloride in Chennai. These measurements, combined with thermodynamic modelling, suggest that in the presence of excess ammonia in Delhi, high local emission of hydrochloric acid partitions into aerosol water. The highly water-absorbing and soluble chloride in the aqueous phase substantially enhances aerosol water uptake through co-condensation, which sustains particle growth, leading to haze and fog formation. We therefore suggest that the high local concentration of gas-phase hydrochloric acid, possibly emitted from plastic-contained waste burning and industry, causes some 50% of the reduced visibility. Our work implies that identifying and regulating gaseous hydrochloric acid emissions could be critical to improve visibility and human health in India.