Reversal of trends in global fine particulate matter air pollution

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Sept. 2, 2023

Ambient fine particulate matter (PM2.5) is the world's leading environmental health risk factor. Quantification needed of regional contributions to changes in global PM2.5 exposure. Here we interpret satellite-derived estimates over 1998-2019 and find a reversal previous growth air pollution, which quantitatively attributed from 13 regions. Global population-weighted (PW) exposure, related both pollution levels population size, increased 1998 (28.3 μg/m3) peak 2011 (38.9 decreased steadily afterwards (34.7 μg/m3 2019). Post-2011 change was exposure reduction China slowed other regions (especially South Asia, Middle East Africa). The post-2011 contributes stagnation PM2.5-attributable mortality increasing benefits per µg/m3 marginal implying urgency mitigation with aging cleaner air.

Language: Английский

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Three-dimensional climatology, trends, and meteorological drivers of global and regional tropospheric type-dependent aerosols: insights from 13 years (2007–2019) of CALIOP observations

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(19), P. 15309 - 15336

Published: Oct. 14, 2021

Abstract. Globally gridded aerosol extinction data from the Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP) during 2007–2019 are utilized to investigate three-dimensional (3D) climatological distribution of tropospheric type-dependent aerosols and identify trends in column optical depth (AOD), partitioned within different altitude regimes, their meteorological drivers. Using detection samples layer aerosols, we also yield a 3D frequency occurrence (FoO) subtypes classified by CALIOP. The results show that coefficient (AEC) shows contrasting vertical patterns over land ocean, former possessing significant geographical dependence, while enhancement AEC latter is mainly located below 1 km. structures AECs, however, strongly dependent on altitude. When total AOD (TAOD) into planetary boundary (PBL) free troposphere (FT), demonstrate PBL FT contribute 62.08 % 37.92 %, respectively, global TAOD averaged daytime nighttime. Yet this CALIOP-based partitioning varies significantly. Among all 12 typical regions interest analyzed, more than 50 lower (0–2 km), contribution less 2 above 6 In average terms, found FoO layers 4.45 largest “clean marine” (1.79 %) smallest continental” (0.05 %). Overall, exhibit pattern similar AEC. resulting trend analyses CALIOP accurately captures regional anomalies TAOD, as observed other satellite measurements reanalysis. Our correlation analysis between factors suggests interannual variability related precipitation (PPT), volumetric soil moisture (VSM), wind speed (WS) particular regions. For instance, positive equatorial central Pacific attributable increased PPT decreased WS. contrast, dry convective dominated dust smoke, variability/trend largely modified VSM driven PPT. Additionally, further these correlations robust significantly weakened or even reversed FT. This highlights superiority using proxy variable for widely applied explore relationships atmospheric pollution meteorology.

Language: Английский

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Fine particulate matter (PM2.5) trends from land surface changes and air pollution policies in China during 1980–2020

Journal of Environmental Management, Journal Year: 2022, Volume and Issue: 326, P. 116847 - 116847

Published: Nov. 25, 2022

Language: Английский

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Obtaining vertical distribution of PM2.5 from CALIOP data and machine learning algorithms

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 805, P. 150338 - 150338

Published: Sept. 15, 2021

Aerosol optical depth (AOD) has been widely used to estimate the near-surface PM2.5 (fine particulate matter with particle size less than 2.5 μm). However, total-column AOD obtained by passive remote sensing instruments can neither distinguish contribution of in various altitude layers nor obtain vertical concentration. In this study, we compared several AOD-PM2.5 models including Extra Trees (ET), Random Forest (RF), Deep Neural Network (DNN), and Gradient Boosting Regression Tree (GBRT), analyzed corresponding results using different altitudes auxiliary data from Cloud-Aerosol Lidar Orthogonal Polarization (CALIOP). The indicate that ET model performs best terms effectiveness feature interpretation on training dataset. We conclude importance bottom layer is higher upper total column AOD. showed regional differences existed optimal height correlation study area. cross-validation manages most appealing overall performance an R2 (RMSE) 0.85 (17.77 μg/m3). Regarding 729 sites involved 73% had > 0.7, region or season achieves better performance. each were corrected weight, concentrations 2015 2019. highlight high concentration area primarily near ground decreases height. Additionally, Beijing-Tianjin-Hebei (−1.80 μg/m3, P < 0.001), Central China (−1.62 Pearl River Delta (−0.66 0.001) show apparent downward trend. believe distribution analysis provide meaningful information for studying air pollution.

Language: Английский

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A global-scale analysis of the MISR Level-3 aerosol optical depth (AOD) product: Comparison with multi-platform AOD data sources

Atmospheric Pollution Research, Journal Year: 2021, Volume and Issue: 12(12), P. 101238 - 101238

Published: Oct. 29, 2021

Language: Английский

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A comprehensive reappraisal of long-term aerosol characteristics, trends, and variability in Asia

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(14), P. 8187 - 8210

Published: July 24, 2023

Abstract. Changes in aerosol loadings and properties are important for the understanding of atmospheric environment climate change. This study investigates characteristics long-term trends aerosols different sizes types Asia from 2000 to 2020 by considering multi-source data novel analysis methods perspectives, all which provides groundwork promoting acquisition new discoveries that past. The geometric mean aggregation method is applied, serial autocorrelation considered avoid overestimation trend significance. Among regions Asia, high values optical depth (AOD) mainly concentrated East (EA) South (SA) closely related population density. AOD EA showed most significant negative trend, with a value -5.28×10-4 per year, owing decreases organic carbon (OC), black (BC), dust aerosols. It also worth noting this observed large-scale decrease OC BC unique phenomenon region around China. In contrast, concentrations SA generally show positive an increased 1.25 × 10−3 year. increase due large emissions fine-mode aerosols, such as sulfate aerosol. Additionally, loading northern has lower variability when compared China Plain, revealing relatively more persistent air pollution situation. Over whole percentage changes seen increases (6.23 %) (17.09 AOD, together (−5.51 %), (−3.07 sea salt (−9.80 AOD. Except anthropogenic emissions, wildfires found summer, whereas differently sized only shows slight small-sized (−3.34 total did not suggests that, perspective, recent years have mostly been offsetting earlier over Asia. To summarize, above findings analyse comprehensive distributions reappraise parameters, will greatly enhance regional global climatology, addition filling gaps breaking through limitations past knowledge.

Language: Английский

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“Investigating and mapping day-night urban heat island and its driving factors using Sentinel/MODIS data and Google Earth Engine. Case study: Greater Cairo, Egypt”

Urban Climate, Journal Year: 2023, Volume and Issue: 52, P. 101729 - 101729

Published: Oct. 27, 2023

Language: Английский

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Accuracy, stability, and continuity of AVHRR, SeaWiFS, MODIS, and VIIRS deep blue long-term land aerosol retrieval in Asia

The Science of The Total Environment, Journal Year: 2022, Volume and Issue: 832, P. 155048 - 155048

Published: April 4, 2022

Language: Английский

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Changes in aerosol loading before, during and after the COVID-19 pandemic outbreak in China: Effects of anthropogenic and natural aerosol

The Science of The Total Environment, Journal Year: 2022, Volume and Issue: 857, P. 159435 - 159435

Published: Oct. 13, 2022

Language: Английский

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Current and Near-Term Earth-Observing Environmental Satellites, Their Missions, Characteristics, Instruments, and Applications

Sensors, Journal Year: 2024, Volume and Issue: 24(11), P. 3488 - 3488

Published: May 28, 2024

Among the essential tools to address global environmental information requirements are Earth-Observing (EO) satellites with free and open data access. This paper reviews those EO from international space programs that already, or will in next decade so, provide of importance sciences describe Earth’s status. We summarize factors distinguishing pioneering placed over past half century, their links modern ones, changing priorities for spaceborne instruments platforms. illustrate broad sweep instrument technologies useful observing different aspects physio-biological surface, spanning wavelengths UV-A at 380 nanometers microwave radar out 1 m. a background on technical specifications each mission its primary instrument(s), types collected, examples applications these observations. websites additional details instrument, history context behind measurements, about design, specifications, measurements.

Language: Английский

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