Enhanced secondary pollution offset reduction of primary emissions during COVID-19 lockdown in China

National Science Review, Journal Year: 2020, Volume and Issue: 8(2)

Published: June 16, 2020

To control the spread of 2019 novel coronavirus (COVID-19), China imposed nationwide restrictions on movement its population (lockdown) after Chinese New Year 2020, leading to large reductions in economic activities and associated emissions. Despite such decreases primary pollution, there were nonetheless several periods heavy haze pollution eastern China, raising questions about well-established relationship between human air quality. Here, using comprehensive measurements modeling, we show that during COVID lockdown was driven by enhancements secondary pollution. In particular, NOx emissions from transportation increased ozone nighttime NO3 radical formation, these increases atmospheric oxidizing capacity turn facilitated formation particulate matter. Our results, afforded tragic natural experiment COVID-19 pandemic, indicate mitigation depends upon a coordinated balanced strategy for controlling multiple pollutants.

Language: Английский

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Ozone pollution in the North China Plain spreading into the late-winter haze season

Proceedings of the National Academy of Sciences, Journal Year: 2021, Volume and Issue: 118(10)

Published: March 1, 2021

Surface ozone is a severe air pollution problem in the North China Plain, which home to 300 million people. Ozone concentrations are highest summer, driven by fast photochemical production of hydrogen oxide radicals (HO

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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Secondary organic aerosol formed by condensing anthropogenic vapours over China’s megacities

Nature Geoscience, Journal Year: 2022, Volume and Issue: 15(4), P. 255 - 261

Published: April 1, 2022

Language: Английский

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Attribution of Air Quality Benefits to Clean Winter Heating Policies in China: Combining Machine Learning with Causal Inference

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(46), P. 17707 - 17717

Published: Feb. 1, 2023

Heating is a major source of air pollution. To improve quality, range clean heating policies were implemented in China over the past decade. Here, we evaluated impacts winter and on quality using novel, observation-based causal inference approach. During 2015-2021, causally increased annual PM2.5, daily maximum 8-h average O3, SO2 by 4.6, 2.5, 2.3 μg m-3, respectively. From 2015 to 2021, PM2.5 Beijing surrounding cities (i.e., "2 + 26" cities) decreased 5.9 m-3 (41.3%), whereas that other northern only 1.2 (12.9%). This demonstrates effectiveness stricter cities. Overall, caused mainland reduce 1.9 from potentially avoiding 23,556 premature deaths 2021.

Language: Английский

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Amplified positive effects on air quality, health, and renewable energy under China’s carbon neutral target

Nature Geoscience, Journal Year: 2024, Volume and Issue: 17(5), P. 411 - 418

Published: April 29, 2024

Abstract China pledged to achieve carbon neutrality by 2060 combat global climate change, yet the resulting multi-aspect domestic impacts are not fully analysed due an incomplete understanding of underlying anthropogenic–natural interactions. Building integrated cross-disciplinary modelling framework that can capture feedbacks changing aerosols on meteorology, here we highlight amplified air quality, human health and renewable energy self-reinforcing synergies China’s neutral target in comparison baseline 2015 2060. We find owing emissions reduction more favourable meteorological conditions caused less aerosol, achieving reduces national population-weighted PM 2.5 concentrations associated premature deaths ~39 μg m − 3 1.13 (95% confidence interval: 0.97–1.29) million while boosting provincial solar (wind) power performance up ~10% (~6%) with mostly decreased resource variability baseline. Enhanced along low-carbon transition may provide additional opportunities address remaining pollution damages upon neutrality. Our results developing polluting countries’ pledge for produce important positive between mitigation, quality improvement enhanced energy, which be via weakened aerosol–meteorology interactions better atmospheric dispersion.

Language: Английский

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Air Quality During COVID-19 Lockdown in the Yangtze River Delta and the Pearl River Delta: Two Different Responsive Mechanisms to Emission Reductions in China

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(9), P. 5721 - 5730

Published: April 2, 2021

Despite the large reduction in anthropogenic activities due to outbreak of COVID-19, air quality China has witnessed little improvement and featured great regional disparities. Here, by combining observational data simulations, this work aims understand diverse response two city clusters, Yangtze River Delta region (YRD) Pearl (PRD), China. Though there was a noticeable drop primary pollutants both regions, differently, maximum daily 8 h average ozone (O3) soared 20.6-76.8% YRD but decreased 15.5-28.1% PRD. In YRD, nitrogen oxide (NOx) reductions enhanced O3 accumulation hence increased secondary aerosol formation. Such an increment organic inorganic aerosols under stationary weather reached up 36.4 10.2%, respectively, which further intensified transport. PRD quite opposite. The emission benefited quality, while transport corresponded increase 17.3 9.3% aerosols, respectively. Apart from meteorology, discrepancy O3-VOCs-NOx relationships determined different responses, indicating that future control shall be regionally specific, instead one-size-fits-all cut. Overall, importance coordinated balanced strategy for multiple is highly emphasized.

Language: Английский

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Aerosol-boundary-layer-monsoon interactions amplify semi-direct effect of biomass smoke on low cloud formation in Southeast Asia

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: Nov. 5, 2021

Abstract Low clouds play a key role in the Earth-atmosphere energy balance and influence agricultural production solar-power generation. Smoke aloft has been found to enhance marine stratocumulus through aerosol-cloud interactions, but its regions with strong human activities complex monsoon circulation remains unclear. Here we show that biomass burning aerosols strongly increase low cloud coverage over both land ocean subtropical southeastern Asia. The degree of this enhancement spatial extent are comparable Southeast Atlantic, even though total emissions Asia only one-fifth those Southern Africa. We find synergetic effect aerosol-cloud-boundary layer interaction is main reason for semi-direct enhanced formation

Language: Английский

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Understanding ozone pollution in the Yangtze River Delta of eastern China from the perspective of diurnal cycles

The Science of The Total Environment, Journal Year: 2020, Volume and Issue: 752, P. 141928 - 141928

Published: Aug. 22, 2020

Language: Английский

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Limited Regional Aerosol and Cloud Microphysical Changes Despite Unprecedented Decline in Nitrogen Oxide Pollution During the February 2020 COVID‐19 Shutdown in China

Geophysical Research Letters, Journal Year: 2020, Volume and Issue: 47(17)

Published: Aug. 25, 2020

Following the emergence of a novel coronavirus in Wuhan, China instituted shutdown measures starting late January and continuing into February 2020 to arrest spread disease. This resulted sharp economic contraction unparalleled recent Chinese history. Satellite retrievals show that nitrogen dioxide pollution declined by an unprecedented amount (~50% regionally) from its expected unperturbed value, but regional-scale column aerosol loadings cloud microphysical properties were not detectably affected. The disparate impact is tied differential impacts shutdown, which transportation, disproportionate source oxide emissions, underwent drastic declines (~90% reductions passenger traffic), whereas industry power generation, responsible for >90% particulate relatively less affected (~20% electricity thermal generation). A combination anomalously warm humid meteorological conditions complex chemical interactions further decreased concentrations likely enhanced secondary formation.

Language: Английский

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