Markedly enhanced levels of peroxyacetyl nitrate (PAN) during COVID-19 in Beijing. (Special Section: The COVID-19 pandemic: linking health, society, and environment.)
Geophysical Research Letters
; 47(19), 2020.
Article
in English
| CAB Abstracts | ID: covidwho-1263468
ABSTRACT
High levels of secondary air pollutants during COVID-19 in China have aroused great concern. In Beijing, measured daily mean peroxyacetyl nitrate (PAN) concentrations reached 4 ppb over the lockdown period (24 January to 15 February), whose averages were 2-3 times that before lockdown (1-23 January). The lockdown PAN levels also reached a high historical record based on our long-term measurements (2016-2019). Unlike ozone and PM2.5, PAN formation depends on less complex photochemistry between NOx and volatile organic compounds (VOCs), providing a novel approach to investigate the wintertime photochemistry during COVID-19. The GEOS-Chem simulations suggest a markedly enhanced photochemistry by a factor of 2 during the lockdown. Change of meteorology featuring with anomalous wind convergence under higher temperatures is the main reason for enhanced photochemical formation of PAN, while chemically nonlinear feedbacks also play a role. Our results suggest implementing targeted VOC emission controls in the context of increasing photochemical pollution over this complex polluted region.
Full text:
Available
Collection:
Databases of international organizations
Database:
CAB Abstracts
Language:
English
Journal:
Geophysical Research Letters
Year:
2020
Document Type:
Article
Similar
MEDLINE
...
LILACS
LIS