Unexpected air pollution with marked emission reductions during the COVID-19 outbreak in China

Science, Journal Year: 2020, Volume and Issue: 369(6504), P. 702 - 706

Published: June 17, 2020

Air pollution epidemic The lockdown enforced in most cities China response to the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) resulted virtual absence motor vehicle traffic and sharply reduced manufacturing activity for several weeks. Le et al. report some anticipated unanticipated effects that this had on air there, including unexpectedly high levels particulate matter abundances haze formation areas. This natural experiment will help assessment mitigation strategies. Science , issue p. 702

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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Environmental effects of stratospheric ozone depletion, UV radiation, and interactions with climate change: UNEP Environmental Effects Assessment Panel, Update 2020

Photochemical & Photobiological Sciences, Journal Year: 2021, Volume and Issue: 20(1), P. 1 - 67

Published: Jan. 1, 2021

Abstract This assessment by the Environmental Effects Assessment Panel (EEAP) of United Nations Environment Programme (UNEP) provides latest scientific update since our most recent comprehensive (Photochemical and Photobiological Sciences, 2019, 18, 595–828). The interactive effects between stratospheric ozone layer, solar ultraviolet (UV) radiation, climate change are presented within framework Montreal Protocol Sustainable Development Goals. We address how these global environmental changes affect atmosphere air quality; human health; terrestrial aquatic ecosystems; biogeochemical cycles; materials used in outdoor construction, energy technologies, fabrics. In many cases, there is a growing influence from seasonality extreme events due to change. Additionally, we assess transmission severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which responsible for COVID-19 pandemic, context linkages with UV radiation Protocol.

Language: Английский

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From COVID-19 to future electrification: Assessing traffic impacts on air quality by a machine-learning model

Proceedings of the National Academy of Sciences, Journal Year: 2021, Volume and Issue: 118(26)

Published: June 21, 2021

Significance We capitalize on large variations of urban air quality during the COVID-19 pandemic and real-time observations traffic, meteorology, pollution in Los Angeles to develop a machine-learning prediction model. Such model can adequately account for nonlinear relationships between emissions, atmospheric chemistry, meteorological factors. Moreover, this enables us identify key drivers air-quality assess effect future traffic-emission controls quality. unambiguously demonstrate that full benefit from fleet electrification cannot be attained if focused only mitigation local vehicle emissions. To continue improve Angeles, off-road emissions those volatile chemical products need more strictly regulated.

Language: Английский

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Introductory lecture: air quality in megacities

Faraday Discussions, Journal Year: 2020, Volume and Issue: 226, P. 9 - 52

Published: Oct. 30, 2020

This introduction provides an overview of air quality in megacities, sources and atmospheric processing emissions, impacts on health climate, mitigation strategies, challenges COVID-19.

Language: Английский

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Deciphering urban traffic impacts on air quality by deep learning and emission inventory

Journal of Environmental Sciences, Journal Year: 2022, Volume and Issue: 124, P. 745 - 757

Published: Jan. 4, 2022

Language: Английский

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Multi-class organic pollutants in atmospheric particulate matter (PM2.5) from a Southwestern Europe industrial area: Levels, sources and human health risk

Environmental Research, Journal Year: 2022, Volume and Issue: 214, P. 114195 - 114195

Published: Aug. 27, 2022

The occurrence of 50 multi-class pollutants comprising 18 polycyclic aromatic hydrocarbons (PAHs), 12 phthalate esters (PAEs), organophosphorus flame retardants (OPFRs), 6 synthetic musk compounds (SMCs) and 2 bisphenols was studied in atmospheric particulate matter (PM2.5) samples collected at an industrial area focused on automotive manufacturing located the Southwestern Atlantic European region (Vigo city, Spain) during 1-year period. Among all quantitated PM2.5 samples, bisphenol A (BPA) most predominant with average concentration 6180 pg m-3, followed by PAHs benzo(b+j)fluoranthene (BbF + BjF) benzo(g,h,i)perylene (BghiP), accounting for 546 m-3 413 respectively. In addition, two OPFRs concerning tris(chloropropyl) phosphate (TCPP) triphenyl phosphine oxide (TPPO) were next following order, 411 367 respectively; being butyl benzyl (BBP) profuse PAE (56.1 average). High relative standard deviations (RSDs) observed whole sampling period, while statistically significant differences only concentrations cold warm seasons. Furthermore, some water-soluble ions metal(oid)s analysed to be used as PM source tracers, whose quite below target levels set current legislation. Data obtained from principal component analysis (PCA) molecular indices suggested a pyrogenic petrogenic origin PAHs, whereas remaining seems attributed resources activity settled area. Moreover, although substantial anthropogenic observed, marine soil resuspension contributions also accounted. Finally, carcinogenic non-carcinogenic risks posed PM2.5-bound inhalation assessed, both averages within safe level considering

Language: Английский

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Changes in tropospheric air quality related to the protection of stratospheric ozone in a changing climate

Photochemical & Photobiological Sciences, Journal Year: 2023, Volume and Issue: 22(5), P. 1129 - 1176

Published: June 13, 2023

Ultraviolet (UV) radiation drives the net production of tropospheric ozone (O

Language: Английский

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Atmospheric Hydroxyl Radical Route Revealed: Interface-Mediated Effects of Mineral-Bearing Microdroplet Aerosol

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 17, 2025

Hydroxyl radical (·OH) plays a crucial role in atmospheric chemistry, regulating the oxidative potential and aerosol composition. This study reveals an unprecedented source of ·OH atmosphere: mineral dust-bearing microdroplet aerosols. We demonstrate that Kaolin clay particles aerosols trigger rapid production upon solar irradiation, with rates reaching order at least 10-3 M s-1. rate is several orders magnitude higher than bulk phase (2.4 × 10-11 s-1) previously known pathways. On this basis, surface-based interfacial estimated to be 8.9 10-5 mol m-2 s-1 air-water-solid interface 1 μm sized particles. The enhanced formation attributed unique features interfaces, where lifespan photoinduced holes was significantly increased due presence strong electric fields air-water interface. further investigated impacts various environmental factors properties on production, including light intensity, relative humidity, particle size, pH. Our findings provide new insights into photochemical processes mediated by aerosols, which are important contributors atmosphere. work advances our understanding chemistry its profound lasting implications for air quality climate.

Language: Английский

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Measurement report: Aircraft observations of ozone, nitrogen oxides, and volatile organic compounds over Hebei Province, China

Atmospheric chemistry and physics, Journal Year: 2020, Volume and Issue: 20(23), P. 14523 - 14545

Published: Nov. 30, 2020

Abstract. To provide insight into the planetary boundary layer (PBL) production of ozone (O3) over North China Plain, Air chemistry Research in Asia (ARIAs) campaign conducted aircraft measurements air pollutants Hebei Province, China, between May and June 2016. We evaluate vertical profiles trace gas species including O3, nitrogen oxides (NOx), carbon monoxide (CO), volatile organic compounds (VOCs) relate to rates O3 production. This analysis shows measured levels ranged from 45 146 ppbv, with peak median concentration (∼ 92 ppbv) occurring 1000 1500 m. The NOx concentrations exhibited strong spatial altitudinal variations, a maximum 53 ppbv. Ratios CO∕CO2 indicate prevalence low-efficiency combustion biomass burning residential coal but some success regional pollution controls compared earlier studies China. Concentrations total VOCs reveal alkanes dominate volume mixing ratio (68 %), sources include vehicular emissions, fuel solvent evaporation, burning. Alkanes alkenes/alkynes are responsible for 74 % VOC reactivity assessed by calculating OH loss rates, while aromatics contribute most formation potential (OFP) (43 %) toluene, m/p-xylene, ethylene, propylene, i-pentane playing significant roles aloft this region. In PBL below 500 m, box model calculations constrained precursors rate mean was ∼ 7 ppbv h−1. Pollution frequently extended above lower free troposphere around 3000 where NO2 ratios 400 pptv) led net up 3 h−1; can travel substantial distances downwind. sensitivity regime is determined be NOx-limited throughout PBL, whereas it more VOC-limited at low altitudes near urban centers, demonstrating that control both needed reduce Hebei.

Language: Английский

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