scholarly journals “Warm cover”: precursory strong signals for haze pollution hidden in the middle troposphere

2021 ◽  
Vol 21 (18) ◽  
pp. 14131-14139
Author(s):  
Xiangde Xu ◽  
Wenyue Cai ◽  
Tianliang Zhao ◽  
Xinfa Qiu ◽  
Wenhui Zhu ◽  
...  
Keyword(s):  
Air Pollution ◽  
Eastern China ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Ambient Atmosphere ◽  
The Tibetan Plateau ◽  
Vertical Diffusion ◽  
Middle Troposphere ◽  
Strong Signal ◽  
Haze Pollution

Abstract. Eastern China (EC), located in the downstream region of the Tibetan Plateau (TP), is a large area with frequent haze pollution. In addition to air pollutant emissions, meteorological conditions are a key inducement for air pollution episodes. Based on the study of the Great Smog of London in 1952 and haze pollution in EC over recent decades, it is found that the abnormal “warm cover” (air–temperature anomalies) in the middle troposphere, as a precursory strong signal, could be connected to severe air pollution events. The convection and vertical diffusion in the atmospheric boundary layer (ABL) were suppressed by a relatively stable structure of warm cover in the middle troposphere leading to ABL height decreases, which were favorable for the accumulation of air pollutants in the ambient atmosphere. The anomalous structure of the troposphere's warm cover not only exist in heavy haze pollution on the daily scale, but also provide seasonal, interannual and interdecadal strong signals for frequently occurring regional haze pollution. It is revealed that a close relationship existed between interannual variations of the TP's heat source and the warm cover strong signal in the middle troposphere over EC. The warming TP could lead to anomalous warm cover in the middle troposphere from the plateau to the downstream EC region and even the entire East Asian region, thus causing frequent winter haze pollution in EC region.

scholarly journals Warm Cover – Precursory Strong Signals hidden in the Middle Troposphere for Haze Pollution

2021 ◽  
Author(s):  
Xiangde Xu ◽  
Wenyue Cai ◽  
Tianliang Zhao ◽  
Xinfa Qiu ◽  
Wenhui Zhu ◽  
...  
Keyword(s):  
Air Pollution ◽  
Eastern China ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Ambient Atmosphere ◽  
Large Area ◽  
Middle Troposphere ◽  
Haze Pollution ◽  
Close Relationship ◽  
Pollution Events

Abstract. Eastern China (EC), located on the downstream region of Tibetan Plateau (TP), is a large area that has become vulnerable to frequent haze. In addition of air pollutant emissions, meteorological conditions were a key inducement for air pollution episodes. Based on the study of the Great Smog of London in 1952 and haze pollution in EC over recent decades, it is found that the abnormal warm cover in the middle troposphere, as a precursory strong signal hidden, could connect to severe air pollution events. The convection and diffusion in the atmospheric boundary layer (ABL) were suppressed by a relatively stable structure of warm cover in the middle troposphere, leading to the ABL height decreases, which were favourable for the accumulation of air pollutants in the ambient atmosphere. The warming TP built the warm cover in the middle troposphere from the plateau to the downstream EC region and even the entire East Asian region. The frequent haze events in EC is connected with a significantly strong warm cover in the interdecadal variability. It is also revealed that a close relationship existed between interannual variations of the TP's heat source and the warm cover hidden in the middle troposphere over EC.

scholarly journals Air pollutant emissions from Chinese households: A major and underappreciated ambient pollution source

2016 ◽  
Vol 113 (28) ◽  
pp. 7756-7761 ◽  
Author(s):  
Jun Liu ◽  
Denise L. Mauzerall ◽  
Qi Chen ◽  
Qiang Zhang ◽  
Yu Song ◽  
...  
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Eastern China ◽  
Pollution Prevention ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Base Case ◽  
Chinese Government ◽  
Industrial Sectors ◽  
Bth Region

As part of the 12th Five-Year Plan, the Chinese government has developed air pollution prevention and control plans for key regions with a focus on the power, transport, and industrial sectors. Here, we investigate the contribution of residential emissions to regional air pollution in highly polluted eastern China during the heating season, and find that dramatic improvements in air quality would also result from reduction in residential emissions. We use the Weather Research and Forecasting model coupled with Chemistry to evaluate potential residential emission controls in Beijing and in the Beijing, Tianjin, and Hebei (BTH) region. In January and February 2010, relative to the base case, eliminating residential emissions in Beijing reduced daily average surface PM2.5 (particulate mater with aerodynamic diameter equal or smaller than 2.5 micrometer) concentrations by 14 ± 7 μg⋅m−3 (22 ± 6% of a baseline concentration of 67 ± 41 μg⋅m−3; mean ± SD). Eliminating residential emissions in the BTH region reduced concentrations by 28 ± 19 μg⋅m−3 (40 ± 9% of 67 ± 41 μg⋅m−3), 44 ± 27 μg⋅m−3 (43 ± 10% of 99 ± 54 μg⋅m−3), and 25 ± 14 μg⋅m−3 (35 ± 8% of 70 ± 35 μg⋅m−3) in Beijing, Tianjin, and Hebei provinces, respectively. Annually, elimination of residential sources in the BTH region reduced emissions of primary PM2.5 by 32%, compared with 5%, 6%, and 58% achieved by eliminating emissions from the transportation, power, and industry sectors, respectively. We also find air quality in Beijing would benefit substantially from reductions in residential emissions from regional controls in Tianjin and Hebei, indicating the value of policies at the regional level.

scholarly journals Climate modulation of the Tibetan Plateau on haze in China

2016 ◽  
Vol 16 (3) ◽  
pp. 1365-1375 ◽  
Author(s):  
X. Xu ◽  
T. Zhao ◽  
F. Liu ◽  
S. L. Gong ◽  
D. Kristovich ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Large Scale ◽  
Climate Changes ◽  
Eastern China ◽  
Atmospheric Stability ◽  
Lower Troposphere ◽  
Pollutant Emissions ◽  
The Tibetan Plateau ◽  
Thermal Forcing ◽  
Haze Pollution

Abstract. Rapid increases in pollutant emissions in conjunction with stagnant meteorological conditions result in haze pollution in China. Recent frequent haze in China has attracted worldwide attention. Here we show a relationship between the haze events and Tibetan Plateau (TP)'s environment and climate changes. Based on observational data taken over recent decades, we identify central-eastern China (CEC) as a climatological large-scale “susceptible region” of frequent haze, which is harbored by the TP with its impact on midlatitude westerly winds. The observational and modeling studies demonstrate that the interannual variations in the thermal forcing of TP are positively correlated with the incidences of wintertime haze over CEC. Further analysis indicates that the climate warming of the TP induced changes in atmospheric circulation, driving frequent haze events in CEC. The frequent haze occurrences in CEC are consistent with decreasing winter monsoon winds, intensifying downward air flows and increasing atmospheric stability in the lower troposphere over the CEC in association with upstream plateau's thermal anomalies. Therefore, variations of haze in China are related to mechanical and thermal forcing by the TP. Our results also suggest that implications of the large TP topography for environment and climate changes should be taken into account for air pollution mitigation policies in China.

scholarly journals Climate modulation of the Tibetan Plateau on haze in China

2015 ◽  
Vol 15 (20) ◽  
pp. 28915-28937 ◽  
Author(s):  
X. Xu ◽  
T. Zhao ◽  
F. Liu ◽  
S. L. Gong ◽  
D. Kristovich ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Large Scale ◽  
Climate Changes ◽  
Eastern China ◽  
Atmospheric Stability ◽  
Lower Troposphere ◽  
Pollutant Emissions ◽  
The Tibetan Plateau ◽  
Thermal Forcing ◽  
Haze Pollution

Abstract. Rapid increases in pollutant emissions in conjunction with stagnant meteorological conditions result in haze pollution in China. Recent frequent haze in China has attracted worldwide attention. Here we show a relationship between the haze events and Tibetan Plateau (TP)'s environment and climate changes. Based on observational data taken over recent decades, we identify central-eastern China (CEC) as a climatological large-scale "susceptible region" of frequent haze, which is harbored by the TP with its impact on mid-latitude westerly winds. The observational and modeling studies demonstrate that the interannual variations in the thermal forcing of TP are positively correlated with the incidences of wintertime haze over CEC. Further analysis indicates that the TP-climate warming induced changes in atmospheric circulation driving frequent haze events in CEC. The frequent haze occurrences in CEC are consistent with decreasing winter monsoon winds, intensifying downward air flows and increasing atmospheric stability in the lower troposphere over the CEC in association with upstream plateau's thermal anomalies. Therefore, variations of haze in China are related to mechanical and thermal forcing by the TP. Our results also suggest that implications of the large TP-topography for environment and climate changes should be taken into account for air pollution mitigation policies in China.

scholarly journals Study on mapping ozone pollution and ozone pollution regime in Cantho city then propose solutions to reduce ozone pollution

2018 ◽  
Vol 1 (6) ◽  
pp. 247-257
Author(s):  
Bang Quoc Ho ◽  
Tam Thoai Nguyen ◽  
Khue Hoang Ngoc Vu
Keyword(s):  
Air Pollution ◽  
Ozone Concentration ◽  
Ambient Air ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Ozone Pollution ◽  
Sensitive Areas ◽  
Study Results ◽  
Can Tho City ◽  
The City

Can Tho City is one the 5th largest city in Vietnam, with hight rate of economic growth and densely populated with 1,251,809 people, butsling traffic activities with 566,593 motobikes and 15,105 cars and hundreds of factories. The air in Can Tho city is polluted by dust and ozone. However, Can Tho city currently does not have a study on the simulation air pollution spread, therefore we do not have an overview on the status of air pollution in order to do not have solutions to limit the increase of pollution status of the city. The purpose of this study is to collect air pollutant emissions from other study. After that, TAPOM model is used to simulate the effects of ozone on the surrounding areas and study the ozone regime in Cantho city. The study results showed that the highest ozone concentration for an hour everage is 196 μg/m3. Compare with national technical regulation about ambient air QCVN 5:2013/BTNMT, ozone concentration is approximately at the allowable limit. The study of ozone regime had identified that VOC sensitive areas are Ninh Kieu district and a part in the south of Binh Thuy district, and NOx sensitive areas are the rested areas of Cantho city. The main cause contributing to increased VOC emission in the central area of the city is motorcycles, NOx emissions in the remaining areas of Cantho city are from the rice production factories. Proposals to protect the air quality in Cantho city are suggested.

scholarly journals Long-term trends and drivers of aerosol pH in eastern China

2021 ◽  
Author(s):  
Min Zhou ◽  
Guangjie Zheng ◽  
Hongli Wang ◽  
Liping Qiao ◽  
Shuhui Zhu ◽  
...  
Keyword(s):  
Air Pollution ◽  
Prevention And Control ◽  
Action Plan ◽  
Health Effect ◽  
Eastern China ◽  
Pollution Prevention ◽  
Control Action ◽  
Haze Pollution ◽  
Pollution Prevention And Control ◽  
And Control

Abstract. Aerosol acidity plays a key role in regulating the chemistry and toxicity of atmospheric aerosol particles. The trend of aerosol pH and its drivers are crucial in understanding the multiphase formation pathways of aerosols. Here, we reported the first trend analysis of aerosol pH from 2011 to 2019 in eastern China. The implementation of the Air Pollution Prevention and Control Action Plan leads to −35.8 %, −37.6 %, −9.6 %, −81.0 % and 1.2 % changes of PM2.5, SO42−, NHx, NVCs and NO3− in YRD during this period. Different from the fast changes of aerosol compositions due to the implementation of the Air Pollution Prevention and Control Action Plan, aerosol pH shows a moderate change of −0.24 unit over the 9 years. Besides the multiphase buffer effect, the opposite effects of SO42− and non-volatile cations changes play key roles in determining the moderate pH trend, contributing to a change of +0.38 and −0.35 unit, respectively. Seasonal variations in aerosol pH were mainly driven by the temperature, while the diurnal variations were driven by both temperature and relative humidity. In the future, SO2, NOx and NH3 emissions are expected to be further reduced by 86.9 %, 74.9 % and 41.7 % in 2050 according to the best health effect pollution control scenario (SSP1-26-BHE). The corresponding aerosol pH in eastern China is estimated to increase by ~0.9, resulting in 8 % more NO3− and 35 % less NH4+ partitioning/formation in the aerosol phase, which suggests a largely reduced benefit of NH3 and NOx emission control in mitigating haze pollution in eastern China.

scholarly journals Wildfire air pollution hazard during the 21st century

2017 ◽  
Vol 17 (14) ◽  
pp. 9223-9236 ◽  
Author(s):  
Wolfgang Knorr ◽  
Frank Dentener ◽  
Jean-François Lamarque ◽  
Leiwen Jiang ◽  
Almut Arneth
Keyword(s):  
Climate Change ◽  
Air Pollution ◽  
Significant Risk ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Anthropogenic Sources ◽  
World Health ◽  
Fire Season ◽  
Worst Case ◽  
The World

Abstract. Wildfires pose a significant risk to human livelihoods and are a substantial health hazard due to emissions of toxic smoke. Previous studies have shown that climate change, increasing atmospheric CO2, and human demographic dynamics can lead to substantially altered wildfire risk in the future, with fire activity increasing in some regions and decreasing in others. The present study re-examines these results from the perspective of air pollution risk, focussing on emissions of airborne particulate matter (PM2. 5), combining an existing ensemble of simulations using a coupled fire–dynamic vegetation model with current observation-based estimates of wildfire emissions and simulations with a chemical transport model. Currently, wildfire PM2. 5 emissions exceed those from anthropogenic sources in large parts of the world. We further analyse two extreme sets of future wildfire emissions in a socio-economic, demographic climate change context and compare them to anthropogenic emission scenarios reflecting current and ambitious air pollution legislation. In most regions of the world, ambitious reductions of anthropogenic air pollutant emissions have the potential to limit mean annual pollutant PM2. 5 levels to comply with World Health Organization (WHO) air quality guidelines for PM2. 5. Worst-case future wildfire emissions are not likely to interfere with these annual goals, largely due to fire seasonality, as well as a tendency of wildfire sources to be situated in areas of intermediate population density, as opposed to anthropogenic sources that tend to be highest at the highest population densities. However, during the high-fire season, we find many regions where future PM2. 5 pollution levels can reach dangerous levels even for a scenario of aggressive reduction of anthropogenic emissions.

Air Pollution Control and its Impacts on Coal Use

1988 ◽  
Vol 6 (6) ◽  
pp. 447-464
Author(s):  
Jan Vernon
Keyword(s):  
Air Pollution ◽  
Pollution Control ◽  
Nuclear Power ◽  
National Policy ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Current Status ◽  
Air Pollution Control ◽  
Federal Republic Of Germany ◽  
Capital Costs

Over the last decade, environmental concerns have played an increasing role in energy decision making, from siting of new energy facilities to national policy changes, such as Sweden's decision to phase out nuclear power. Concern about atmospheric pollution from fossil fuel combustion, reflected in increasingly strict emission limits, has imposed additional costs and technical demands on coal-fired plants. Estimates from the Federal Republic of Germany, the USA and the OECD indicate that air pollution control can account for a third of the capital costs for a new coal-fired power plant. This article outlines the current status of regulations on air pollutant emissions from coal-fired plants, describes action being taken to meet regulations and its potential impacts on coal utilisation. The article focuses on sulphur dioxide and nitrogen oxides, which have seen major recent developments in regulations and control methods.

scholarly journals EURODELTA-Trends, a multi-model experiment of air quality hindcast in Europe over 1990–2010

2017 ◽  
Vol 10 (9) ◽  
pp. 3255-3276 ◽  
Author(s):  
Augustin Colette ◽  
Camilla Andersson ◽  
Astrid Manders ◽  
Kathleen Mar ◽  
Mihaela Mircea ◽  
...  
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Boundary Conditions ◽  
Radiative Forcing ◽  
Regional Scale ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Mitigation Measures ◽  
Modelling Experiment ◽  
Technical Features

Abstract. The EURODELTA-Trends multi-model chemistry-transport experiment has been designed to facilitate a better understanding of the evolution of air pollution and its drivers for the period 1990–2010 in Europe. The main objective of the experiment is to assess the efficiency of air pollutant emissions mitigation measures in improving regional-scale air quality. The present paper formulates the main scientific questions and policy issues being addressed by the EURODELTA-Trends modelling experiment with an emphasis on how the design and technical features of the modelling experiment answer these questions. The experiment is designed in three tiers, with increasing degrees of computational demand in order to facilitate the participation of as many modelling teams as possible. The basic experiment consists of simulations for the years 1990, 2000, and 2010. Sensitivity analysis for the same three years using various combinations of (i) anthropogenic emissions, (ii) chemical boundary conditions, and (iii) meteorology complements it. The most demanding tier consists of two complete time series from 1990 to 2010, simulated using either time-varying emissions for corresponding years or constant emissions. Eight chemistry-transport models have contributed with calculation results to at least one experiment tier, and five models have – to date – completed the full set of simulations (and 21-year trend calculations have been performed by four models). The modelling results are publicly available for further use by the scientific community. The main expected outcomes are (i) an evaluation of the models' performances for the three reference years, (ii) an evaluation of the skill of the models in capturing observed air pollution trends for the 1990–2010 time period, (iii) attribution analyses of the respective role of driving factors (e.g. emissions, boundary conditions, meteorology), (iv) a dataset based on a multi-model approach, to provide more robust model results for use in impact studies related to human health, ecosystem, and radiative forcing.

Sign in / Sign up

Export Citation Format

Share Document