Tracking Daily Concentrations of PM_2.5 Chemical Composition in China since 2000

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(22), P. 16517 - 16527

Published: Nov. 1, 2022

PM2.5 chemical components play significant roles in the climate, air quality, and public health, vary due to their different physicochemical properties. Obtaining accurate timely updated information on China's composition is basis for research environmental management. Here, we developed a full-coverage near-real-time data set at 10 km spatial resolution since 2000, combining Weather Research Forecasting-Community Multiscale Air Quality modeling system, ground observations, machine learning algorithm, multisource-fusion data. our are good agreement with available observations (correlation coefficients range from 0.64 0.75 monthly scale 2000 2020 0.67 0.80 daily 2013 2020; most normalized mean biases within ±20%). Our reveals long-term trends China, especially rapid decreases after sulfate, nitrate, ammonium, organic matter, black carbon, rate of -9.0, -7.2, -8.1, -8.4, -9.2% per year, respectively. The day-to-day variability also well captured, including evolutions distribution shares components. As part Tracking Pollution China (http://tapdata.org.cn), this daily-updated provides large opportunities health climate as policy-making China.

Language: Английский

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Spatio-temporal patterns of air pollution in China from 2015 to 2018 and implications for health risks

Environmental Pollution, Journal Year: 2019, Volume and Issue: 258, P. 113659 - 113659

Published: Nov. 23, 2019

Language: Английский

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Explosive Secondary Aerosol Formation during Severe Haze in the North China Plain

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(4), P. 2189 - 2207

Published: Feb. 4, 2021

Severe haze events with exceedingly high-levels of fine aerosols occur frequently over the past decades in North China Plain (NCP), exerting profound impacts on human health, weather, and climate. The development effective mitigation policies requires a comprehensive understanding formation mechanisms, including identification quantification sources, formation, transformation aerosol species. Haze evolution this region exhibits distinct physical chemical characteristics from clean to polluted periods, as evident increasing stagnation relative humidity, but decreasing solar radiation well explosive secondary formation. latter is attributed highly elevated concentrations precursor gases reflected by rapid increases particle number mass concentrations, both corresponding nonequilibrium processes. Considerable new knowledge has been acquired understand processes regulating particularly light progress elucidating mechanisms. This review synthesizes recent advances highlighting several critical chemical/physical processes, that is, growth driven photochemistry aqueous chemistry interaction between atmospheric stability. Current challenges future research priorities are also discussed.

Language: Английский

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Himawari-8-derived diurnal variations in ground-level PM<sub>2.5</sub> pollution across China using the fast space-time Light Gradient Boosting Machine (LightGBM)

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(10), P. 7863 - 7880

Published: May 25, 2021

Abstract. Fine particulate matter with a diameter of less than 2.5 µm (PM2.5) has been used as an important atmospheric environmental parameter mainly because its impact on human health. PM2.5 is affected by both natural and anthropogenic factors that usually have strong diurnal variations. Such information helps toward understanding the causes air pollution, well our adaptation to it. Most existing products derived from polar-orbiting satellites. This study exploits use next-generation geostationary meteorological satellite Himawari-8/AHI (Advanced Himawari Imager) document variation in PM2.5. Given huge volume data, based idea gradient boosting, highly efficient tree-based Light Gradient Boosting Machine (LightGBM) method involving spatiotemporal characteristics namely space-time LightGBM (STLG) model, developed. An hourly dataset for China (i.e., ChinaHighPM2.5) at 5 km spatial resolution aerosol additional variables. Hourly estimates (number data samples = 1 415 188) are correlated ground measurements (cross-validation coefficient determination, CV-R2 0.85), root-mean-square error (RMSE) mean absolute (MAE) 13.62 8.49 µg m−3, respectively. Our model captures variations showing pollution increases gradually morning, reaching peak about 10:00 LT (GMT+8), then decreases steadily until sunset. The proposed approach outperforms most traditional statistical regression machine-learning models much lower computational burden terms speed memory, making it suitable routine monitoring.

Language: Английский

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Satellite UV-Vis spectroscopy: implications for air quality trends and their driving forces in China during 2005–2017

Light Science & Applications, Journal Year: 2019, Volume and Issue: 8(1)

Published: Nov. 13, 2019

Abundances of a range air pollutants can be inferred from satellite UV-Vis spectroscopy measurements by using the unique absorption signatures gas species. Here, we implemented several spectral fitting methods to retrieve tropospheric NO2, SO2, and HCHO ozone monitoring instrument (OMI), with radiative simulations providing necessary information on interactions scattered solar light within atmosphere. We analyzed spatial distribution temporal trends satellite-observed over eastern China during 2005-2017, especially in heavily polluted regions. found significant decreasing NO2 SO2 since 2011 most regions, despite varying features turning points. In contrast, an overall increasing trend was identified for these regions recent years. Furthermore, generalized additive models were understand driving forces quality assess effectiveness emission controls. Our results indicated that although meteorological parameters, such as wind, water vapor, radiation temperature, mainly dominated day-to-day seasonal fluctuations pollutants, anthropogenic emissions played role long-term variation ambient concentrations past 13 Generally, declines could attributed reductions due effective policies, opposite may urge need control volatile organic compound (VOC) emissions.

Language: Английский

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Long-term characterization of aerosol chemistry in cold season from 2013 to 2020 in Beijing, China

Environmental Pollution, Journal Year: 2020, Volume and Issue: 268, P. 115952 - 115952

Published: Nov. 3, 2020

Language: Английский

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Spatio-Temporal Variations of the PM2.5/PM10 Ratios and Its Application to Air Pollution Type Classification in China

Frontiers in Environmental Science, Journal Year: 2021, Volume and Issue: 9

Published: June 14, 2021

Particulate Matter (PM) is an important indicator of the degree air pollution. The PM type and ratio coarse fine particles determine ability to affect human health atmospheric processes. Using observation data across country from 2015 2018, this study investigates distribution proportion 2.5 10 at different temporal spatial scales in mainland China; clarifies , /PM ratios interrelation; classifies dust, mixed, anthropogenic aerosol. It shows that annual average concentration decreased by 10.55 8.78 μg m −3 4 years. show obvious while seasonal variations. high winter low summer, spring, summer autumn. Differently, are highest winter, lowest spring. strong independence on implying it can provide extra information about aerosol pollution such as type. A classification method types then further proposed based probability function (PDF) morphology ratios. results dust mainly lies west Hu-Line, mixed distributes near dominates over North China Plain cities southern China. insights into China’s future clean policy making environmental research.

Language: Английский

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Characteristics, secondary transformation, and health risk assessment of ambient volatile organic compounds (VOCs) in urban Beijing, China

Atmospheric Pollution Research, Journal Year: 2021, Volume and Issue: 12(3), P. 33 - 46

Published: Jan. 21, 2021

Language: Английский

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Air pollution and soiling implications for solar photovoltaic power generation: A comprehensive review

Applied Energy, Journal Year: 2021, Volume and Issue: 298, P. 117247 - 117247

Published: June 18, 2021

Language: Английский

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Ambient nitro-aromatic compounds – biomass burning versus secondary formation in rural China

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(3), P. 1389 - 1406

Published: Feb. 2, 2021

Abstract. Nitro-aromatic compounds (NACs) were measured hourly at a rural site in China during wintertime to monitor the changes due local and regional impacts of biomass burning (BB). Concurrent continuous measurements concentrations 16 NACs gas particle phases performed with time-of-flight chemical ionization mass spectrometer (CIMS) equipped Filter Inlet for Gases AEROsols (FIGAERO) unit using iodide as reagent ion. accounted <2 % concentration organic matter (OM) total particulate (PM), but these can reach high 1000 ng m−3 (299 avg), suggesting that they may contribute significantly radiative forcing effects atmospheric particles. Levels gas-phase highest daytime (15:00–16:00 time, LT), smaller night-time peak around 20:00 LT. Box-model simulations showed this occurred because rate NAC production from sources exceeded loss, which mainly via OH reaction lesser degree photolysis. Data gathered extended periods contributions primary BB (resulting 40 %–60 increases concentrations) used characterize individual respect gas–particle partitioning secondary processes (i.e. photochemical smog). On days without extensive BB, formation was dominant source NACs, levels correlated strongly ambient ozone concentration. Analyses regionally aged plumes sampled on allowed precursors such phenol catechol be linked their derivatives nitrophenol nitrocatechol). Correlation analysis time resolution data box-model simulation results constrained relationships between demonstrated contribution processes. Furthermore, 13 NACS classified according or process. Primary emission (accounting 60 %–70 5 studied also significant source. Photochemical smog thus has important brown carbon even dominated by air pollution China.

Language: Английский

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