Study of the PM2.5 growth processes during 2013 to 2016 in the NCP and YRD regions, China
Abstract
The regions of the North China Plain (NCP) and the Yangtze River Delta (YRD) are the most developed and heavily polluted regions in China. Observational studies revealed 'explosive' PM2.5 growth frequently occurs in the two regions. To investigate the characteristics and controlling factors of the growth processes in the two regions, we analyzed all the PM2.5 growth processes from clean condition (i.e., < 35μgm-3) to heavy pollution condition (i.e., > 150μgm-3) in the major cities located in the two regions using hourly monitored PM2.5 concentration. PM2.5 rising rates (PMRR) and dynamic growth duration were calculated to illustrate the characteristics of the growth processes. Hourly particulate chemical composition measurement data and meteorological data are also analyzed to further identify the controlling factors of the PM2.5 growth processes. 171 and 77 PM2.5 growth processes are identified in Beijing (BJ) and Shanghai (SH), respectively, during 2013-2016. The 4-year average PMRR in BJ and SH is 7.11±9.82 μgm-3h-1 and 6.71±6.89 μgm-3h-1, respectively. Clear difference is observed in the composition contributions to the growth processes between BJ and SH. Secondary inorganic aerosols (sulfate and nitrate) components increase rapidly in the PM2.5 growth processes of BJ and SH. In SH, the growth rate of nitrate increased faster than sulfate in the growth processes obviously. Our research suggests that the PM2.5 growth processes would likely relate to meteorological changes, especially WD, WS, T and RH. The dominant wind direction of BJ and SH in growth processes was southerly and westerly winds respectively. Specific WD and high RH can be favorable to the PM2.5 growth processes. Besides secondary transformation of aerosols and stagnant meteorological conditions, regional transport from highly polluted areas is also important for the PM2.5 growth processes of BJ and SH.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.A43L3277H
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0317 Chemical kinetic and photochemical properties;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0365 Troposphere: composition and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE