Ambient Particles (PM10, PM2.5 and PM1.0) and PM2.5 Chemical Components in Western Yangtze River Delta (YRD): An Overview of Data from 1-year Online Continuous Monitoring at Nanjing

Abstract

Understanding particle chemical composition is important in source apportionment and health impact assessment. Since 2012, a Complex Air Pollution Research Station located on the top roof of a 22-floor building (*80 m) in Jiangsu Provincial Academy of Environmental Science was established as a platform to characterize components and temporal variations of hazy and air transport in the region, so as to provide scientific supports on Joint Prevention and Control of Regional Air Pollution control in the Yangtze River Delta. Here, based on 1-year online measurement, we present a preliminary result on occurrence of ambient particles and chemical components, and reconstructed light extinction coefficients based on measured species. In 2015, the annual average concentration of PM 2.5 was 68 ± 40 lg/m 3 , comprising up to nearly 75% of the total PM 10 . The submicron PM 1.0 had an annual average concentration of 48 ± 28 lg/m 3 and contributed about 70% of the total PM 2.5 mass. Secondary inorganic composition including sulfate, nitrate and ammonium (SNA) was the major fraction of PM 2.5 , accounting for *70% on an annual average. The estimated light extinction of ambient particle averaged at 422 ± 256 Mm -1 , of which 412 ± 257 Mm -1 was induced by fine PM 2.5 . SNA contributed largely to the light extinction induced by fine PM 2.5 (about 72%), followed by organic matter (18%).During the high-pollution episodes, the mass fraction of SNA increased notably, calling for necessary controls on key gaseous precursors.

Sources of volatile organic compounds and policy implications for regional ozone pollution control in an urban location of Nanjing, East China

“…Nanjing, located in the western part of the YRD region, is one of the most urbanized and industrialized areas in the world, and consequently it experiences severe air pollution. The site is located downwind of both Nanjing city center and the wider YRD region (Zhao et al, 2017;Zhou et al, 2017), and it is therefore ideally placed to determine the combined impacts of VOCs from both local and regional atmospheric pollution.…”

Application of Positive Matrix Factorization in the Identification of the Sources of PM2.5 in Taipei City

“…Air quality monitoring stations analyze only the hourly concentrations of PM 10 and PM 2.5 , and such information provides only quantitative trends in the PM 10 and PM 2.5 concentrations for determining the level of pollution [ 21 , 22 ]. This analysis is not sufficient for determining the pollution sources of PM 2.5 .…”

Reply to referee #2

“…Therefore, our BC aerosol observations in Beijing were not a special case. In China, high concentrations of BC aerosols under polluted conditions always occur on a regional scale due to intense BC emissions (Zhang et al, 2009; and significant regional transport (Zhao et al, 2013;Wang et al, 2014a;Zheng et al, 2015). Our findings in Beijing can provide some implication in the difference of BC radiative forcing in other regions among different air pollution levels.…”