Articles | Volume 21, issue 10
Atmos. Chem. Phys., 21, 8341–8356, 2021
Atmos. Chem. Phys., 21, 8341–8356, 2021

Research article 01 Jun 2021

Research article | 01 Jun 2021

Significant contrasts in aerosol acidity between China and the United States

Bingqing Zhang et al.

Data sets

Comprehensive Observation Network for Air Pollution in Beijing-Tianjin-Hebeiand Its Surrounding Area China National Environmental Monitoring Centre

Observational data in the USA (CASTNET) United States Environmental Protection Agency

Ammonia Monitoring Network (AMoN) National Atmospheric Deposition Program

Model code and software

CMAQv5.0.2 US EPA Office of Research and Development

ISORROPIA II: a computationally efficient thermodynamic equilibrium model for K+–Ca2+–Mg2+–NH4+–Na+–SO42−–NO3−–Cl−–H2O aerosols ( Fountoukis, C. and Nenes, A.

Short summary
Extended ground-level measurements are coupled with model simulations to comprehensively compare the aerosol acidity in China and the United States. Aerosols in China are significantly less acidic than those in the United States, with pH values 1–2 units higher. Higher aerosol mass concentrations and the abundance of ammonia and ammonium in China, compared to the United States, are leading causes of the pH difference between these two countries.
Final-revised paper