We apply an online-coupled meteorology-chemistry model (WRF-Chem) embedded with an improved process analysis to examine aerosol-radiation feedback (ARF) impacts on effectiveness of emission control due to Coronavirus Disease 2019 (COVID-19) lockdown over North China Plain. Emission reduction alone induces PM2.5 decrease by 16.3 μg m-3 and O3 increase by 10.2 ppbv during COVID-19 lockdown. The ARF enhances PM2.5 decrease by 2.7 μg m-3 (16.6%) and O3 increase by 0.8 ppbv (7.8%). The ARF-induced enhancement of PM2.5 decline is mostly attributed to aerosol chemistry process, while enhancement of O3 rise is ascribed to physical advection and vertical mixing processes. A set of sensitivity experiments with emission reductions in different degrees indicate that the ARF-induced enhancements of PM2.5 declines (O3 rises) follow a robust linear relationship with the emission-reduction-induced PM2.5 decreases. The fitted relationship has an important implication for assessing the effectiveness of emission abatement at any extent.
Keyphrases
- particulate matter
- air pollution
- water soluble
- coronavirus disease
- polycyclic aromatic hydrocarbons
- heavy metals
- high glucose
- diabetic rats
- randomized controlled trial
- systematic review
- drug induced
- sars cov
- physical activity
- oxidative stress
- solid state
- radiation therapy
- drug discovery
- tertiary care
- radiation induced