Satellite-derived PM2.5 concentration trends over Eastern China from 1998 to 2016: Relationships to emissions and meteorological parameters

Gui, Ke; Che, Huizheng; Wang, Yaqiang; Hong, Wang; Zhang, Lei; Zhao, Huiling; Zheng, Yu; Sun, Tianze; Zhang, Xiaoye

doi:10.1016/j.envpol.2019.01.056

Cited by 183 publications

(75 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The large reduction in PM1 concentration reflects the effectiveness of pollution abatement strategies. Satellite-derived estimates also showed an evident decrease in PM2.5 concentration in North China in recent years (Gui et al, 2019).…”

Section: Overall Variations In Aerosol Characteristics From 2014 To 2017mentioning

confidence: 86%

Rapid transition in winter aerosol composition in Beijing from 2014 to 2017: response to clean air actions

Li¹,

Cheng²,

Zhang³

et al. 2019

Preprint

View full text Add to dashboard Cite

Abstract. The clean air actions implemented by the Chinese government in 2013 have led to significantly improved air quality in Beijing. In this work, we combined the in-situ measurements of the chemical components of submicron particles (PM1) in Beijing during the winters of 2014 and 2017 and a regional chemical transport model to investigate the impact of clean air actions on aerosol chemistry and quantify the relative contributions of anthropogenic emissions, meteorological conditions, and regional transport to the changes in aerosol chemical composition from 2014 to 2017. We found that the average PM1 concentration in winter in Beijing decreased by 49.5&#8201;% from 2014 to 2017 (from 66.2&#8201;&#956;g&#8201;m&#8722;3 to 33.4&#8201;&#956;g&#8201;m&#8722;3). Sulfate exhibited a much larger decline than nitrate and ammonium, which led to a rapid transition from sulfate-driven to nitrate-driven aerosol pollution during the wintertime. Organic aerosol (OA), especially coal combustion OA, and black carbon also showed large decreasing rates, indicating the effective emission control of coal combustion and biomass burning. The decreased sulfate contribution and increased nitrate fraction were highly consistent with the much faster emission reductions in sulfur dioxide (SO2) due to phasing out coal in Beijing compared to reduction in nitrogen oxides emissions estimated by bottom-up inventory. The chemical transport model simulations with these emission estimates reproduced the relative changes in aerosol composition and suggested that the reduced emissions in Beijing and its surrounding regions played a dominant role. The variations in meteorological conditions and regional transport contributed much less to the changes in aerosol concentration and its chemical composition during 2014&#8211;2017 compared to the decreasing emissions. Finally, we observed that changes in precursor emissions also altered the aerosol formation mechanisms. The decreased SO2 emissions suppressed the rapid formation of secondary sulfate through heterogeneous reactions. The observed explosive growth of sulfate at a relative humidity (RH) greater than 50&#8201;% in 2014 was delayed to a higher RH of 70&#8201;% in 2017. Thermodynamic simulations showed that the decreased sulfate and nitrate concentrations have lowered the aerosol water content, particle acidity, and ammonium particle fraction. The results in this study demonstrated the response of aerosol chemistry to the stringent clean air actions and identified that the anthropogenic emission reductions are a major driver, which could help to further guide air pollution control strategies in China.

show abstract

Section: Overall Variations In Aerosol Characteristics From 2014 To 2017mentioning

confidence: 86%

Rapid transition in winter aerosol composition in Beijing from 2014 to 2017: response to clean air actions

Li¹,

Cheng²,

Zhang³

et al. 2019

Preprint

View full text Add to dashboard Cite

show abstract

“…Meteorology plays significant roles in air pollution formation, transport, deposition and transformation and unfavorable meteorological condition could bring severe pollution days even the total emission is reduced (Shi et al, 2018;Xu et al, 2016;Li et al, 2017c;Cai et al, 2018;Gui et al, 2019;Wang et al, 2019b). In the pollution period of December 20-26, 2015 in BTH region, about 34% increasing of PM 2.5 are believed due to adverse meteorological condition (Ma et al, 2020).…”

Section: Introductionmentioning

confidence: 99%

Severe air pollution events not avoided by reduced anthropogenic activities during COVID-19 outbreak

Wang

Chen

Zhu

et al. 2020

Resources, Conservation and Recycling

596

520

View full text Add to dashboard Cite

“…The optical properties of the aerosol determine the particles' direct effects on the Earth's radiative balance and weather-climate change (Ramanathan et al, 2001;Eck et al, 2005;Myhre, 2009;Che et al, 2019a;Li et al, 2016). Aerosol optical depth (AOD) is one of the key measures of the total aerosol extinction effects on climate (Breon et al, 2002), and the extinction Ångström exponent (EAE), with spectral dependence, can be used to obtain the information about aerosol size distributions (Gobbi et al, 2007;Eck et al, 1999;Zheng et al, 2017). The aerosols' absorptivity depends on particle composition and is a key determinant to calculate the direct aerosol radiative effect (Haywood and Shine, 1995;Li et al, 2016), and the singlescattering albedo (SSA) is a parameter that has the spectral dependence to distinguish major aerosol particle types (Jacobson et al, 2000;Dubovik et al, 2002;Gelencser, 2004;Russell et al, 2010;Giles et al, 2012).…”

Section: Introductionmentioning

confidence: 99%

Spatial distribution of aerosol microphysical and optical properties and direct radiative effect from the China Aerosol Remote Sensing Network

et al. 2019

Self Cite

View full text Add to dashboard Cite

Abstract. Multi-year observations of aerosol microphysical and optical properties, obtained through ground-based remote sensing at 50 China Aerosol Remote Sensing Network (CARSNET) sites, were used to characterize the aerosol climatology for representative remote, rural, and urban areas over China to assess effects on climate. The annual mean effective radii for total particles (ReffT) decreased from north to south and from rural to urban sites, and high total particle volumes were found at the urban sites. The aerosol optical depth at 440 nm (AOD440 nm) increased from remote and rural sites (0.12) to urban sites (0.79), and the extinction Ångström exponent (EAE440–870 nm) increased from 0.71 at the arid and semi-arid sites to 1.15 at the urban sites, presumably due to anthropogenic emissions. Single-scattering albedo (SSA440 nm) ranged from 0.88 to 0.92, indicating slightly to strongly absorbing aerosols. Absorption AOD440 nm values were 0.01 at the remote sites versus 0.07 at the urban sites. The average direct aerosol radiative effect (DARE) at the bottom of atmosphere increased from the sites in the remote areas (−24.40 W m−2) to the urban areas (−103.28 W m−2), indicating increased cooling at the latter. The DARE for the top of the atmosphere increased from −4.79 W m−2 at the remote sites to −30.05 W m−2 at the urban sites, indicating overall cooling effects for the Earth–atmosphere system. A classification method based on SSA440 nm, fine-mode fraction (FMF), and EAE440–870 nm showed that coarse-mode particles (mainly dust) were dominant at the rural sites near the northwestern deserts, while light-absorbing, fine-mode particles were important at most urban sites. This study will be important for understanding aerosol climate effects and regional environmental pollution, and the results will provide useful information for satellite validation and the improvement of climate modelling.

show abstract

Satellite-derived PM2.5 concentration trends over Eastern China from 1998 to 2016: Relationships to emissions and meteorological parameters

Cited by 183 publications

References 45 publications

Rapid transition in winter aerosol composition in Beijing from 2014 to 2017: response to clean air actions

Rapid transition in winter aerosol composition in Beijing from 2014 to 2017: response to clean air actions

Severe air pollution events not avoided by reduced anthropogenic activities during COVID-19 outbreak

Spatial distribution of aerosol microphysical and optical properties and direct radiative effect from the China Aerosol Remote Sensing Network

Contact Info

Product

Resources

About