Persistent sulfate formation from London Fog to Chinese haze
Top Cited Papers
- 14 November 2016
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 113 (48), 13630-13635
- https://doi.org/10.1073/pnas.1616540113
Abstract
Sulfate aerosols exert profound impacts on human and ecosystem health, weather, and climate, but their formation mechanism remains uncertain. Atmospheric models consistently underpredict sulfate levels under diverse environmental conditions. From atmospheric measurements in two Chinese megacities and complementary laboratory experiments, we show that the aqueous oxidation of SO2 by NO2 is key to efficient sulfate formation but is only feasible under two atmospheric conditions: on fine aerosols with high relative humidity and NH3 neutralization or under cloud conditions. Under polluted environments, this SO2 oxidation process leads to large sulfate production rates and promotes formation of nitrate and organic matter on aqueous particles, exacerbating severe haze development. Effective haze mitigation is achievable by intervening in the sulfate formation process with enforced NH3 and NO2 control measures. In addition to explaining the polluted episodes currently occurring in China and during the 1952 London Fog, this sulfate production mechanism is widespread, and our results suggest a way to tackle this growing problem in China and much of the developing world.Keywords
Funding Information
- Robert A. Foundation (A-1417)
- National Natural Science Foundation of China (41325014)
This publication has 62 references indexed in Scilit:
- Sulfate-nitrate-ammonium aerosols over China: response to 2000–2015 emission changes of sulfur dioxide, nitrogen oxides, and ammoniaAtmospheric Chemistry and Physics, 2013
- Multiphase chemistry of atmospheric aminesPhysical Chemistry Chemical Physics, 2013
- Aerosol composition, sources and processes during wintertime in Beijing, ChinaEgusphere, 2013
- Nucleation and Growth of Nanoparticles in the AtmosphereChemical Reviews, 2011
- Intensification of Pacific storm track linked to Asian pollutionProceedings of the National Academy of Sciences of the United States of America, 2007
- Experimental product study of the OH-initiated oxidation of m-xyleneJournal of Photochemistry and Photobiology A: Chemistry, 2005
- Effect of clouds on photolysis and oxidants in the troposphereJournal of Geophysical Research: Atmospheres, 2003
- Counting the Cost of London's Killer SmogScience, 2002
- Hydrolysis of N2O5 and ClONO2 on the H2SO4/HNO3/H2O ternary solutions under stratospheric conditionsGeophysical Research Letters, 1995
- Rate constant for the reaction of nitrogen dioxide with sulfur(IV) over the pH range 5.3-13Environmental Science & Technology, 1988