scholarly journals Exploring the inconsistent variations in atmospheric primary and secondary pollutants during the 2016 G20 summit in Hangzhou, China: implications from observations and models

2020 ◽  
Vol 20 (9) ◽  
pp. 5391-5403
Author(s):  
Gen Zhang ◽  
Honghui Xu ◽  
Hongli Wang ◽  
Likun Xue ◽  
Jianjun He ◽  
...  
Keyword(s):  
Eastern China ◽  
Fuel Combustion ◽  
Control Measures ◽  
The Other ◽  
Pollutant Emissions ◽  
Solar Irradiation ◽  
Biogenic Emissions ◽  
Total Production ◽  
Photochemical Pollution ◽  
Emission Controls

Abstract. Complex aerosol and photochemical pollution (ozone and peroxyacetyl nitrate, PAN) frequently occur in eastern China, and mitigation strategies to effectively alleviate both kinds of pollution are urgently needed. Although the effectiveness of powerful control measures implemented by the Chinese State Council has been comprehensively evaluated in terms of reducing atmospheric primary pollutants, the effectiveness in mitigating photochemical pollution is less assessed and therefore the underlying mechanisms are still poorly understood. The stringent emission controls implemented from 24 August to 6 September 2016 during the summit for the Group of Twenty (G20) provide us a unique opportunity to address this issue. Surface concentrations of atmospheric O3, PAN, and their precursors including volatile organic compounds (VOCs) and nitrogen dioxides (NOx), in addition to the other trace gases and particulate matter, were measured at the National Reference Climatological Station (NRCS) (30.22∘ N, 120.17∘ E, 41.7 m a.s.l) in urban Hangzhou. We found significant decreases in atmospheric PAN, NOx, total VOCs, PM2.5, and sulfur dioxide (SO2) under the unfavorable meteorological conditions during G20 (DG20) relative to the adjacent period before and after G20 (BG20 and AG20), indicating that the powerful control measures were effective in reducing the pollutant emissions in Hangzhou. Unlike with the other pollutants, daily maximum 8 h average (DMA8) O3 exhibited a slight increase and then decrease from BG20 to AG20, which was mainly attributed to the variation in the solar irradiation intensity and regional transport in addition to the contribution from the implementation of stringent control measures. Results from an observation-based chemical model (OBM) indicated that acetaldehyde and methylglyoxal (MGLY) were the most important second-generation precursors of PAN, accounting for 37.3 %–51.6 % and 22.8 %–29.5 % of the total production rates including the reactions of OVOCs, propagation of other radicals, and other minor sources. Moreover, we confirmed the production of PAN and O3 was sensitive to VOCs throughout the whole period, specifically dominated by aromatics in BG20 and DG20 but by alkenes in AG20. These findings suggested that reducing emissions of aromatics, alkenes, and alkanes would mitigate photochemical pollution including PAN and O3. Source appointment results attributed the reductions of VOC source and ozone formation potentials (OFPs) during G20 to the effective emission controls on traffic (vehicle exhaust) and industrial processes (solvent utilization and industrial manufacturing). However, fuel combustion and biogenic emissions both weakened such an effect with a sizable contribution to the VOC mixing ratios (18.8 % and 20.9 %) and OFPs (25.6 % and 17.8 %), especially during the latter part of G20 (G20 II) when anthropogenic VOCs were substantially reduced. This study highlights the effectiveness of stringent emission controls in relation to traffic and industrial sources, but a coordinated program related to controlling fuel combustion and biogenic emissions is also required to address secondary pollution.

scholarly journals Exploring the inconsistent variations in atmospheric primary and secondary pollutants during the G20 2016 Summit in Hangzhou, China: implications from observation and model

2020 ◽  
Author(s):  
Gen Zhang ◽  
Honghui Xu ◽  
Hongli Wang ◽  
Likun Xue ◽  
Jianjun He ◽  
...  
Keyword(s):  
Eastern China ◽  
Meteorological Condition ◽  
Fuel Combustion ◽  
Mitigation Strategies ◽  
Control Measures ◽  
The Other ◽  
Solar Irradiation ◽  
Total Production ◽  
Photochemical Pollution ◽  
Emission Controls

Abstract. Complex aerosol and photochemical pollution (ozone and peroxyacetyl nitrate (PAN)) frequently occur in eastern China and mitigation strategies to effectively alleviate both kinds of pollution are urgently needed. Although the effectiveness of powerful control measures implemented by the Chinese State Council has been comprehensively evaluated on reducing atmospheric primary pollutants, the effectiveness on mitigating photochemical pollution is less assessed and therein the underlying mechanisms are still poorly understood. The stringent emission controls implemented from 24 August to 6 September 2016 during the summit for Group of Twenty Finance Ministers and Central Bank Governors (G20) provides us a unique opportunity to address this issue. Surface concentrations of atmospheric O3, PAN, and their precursors including volatile organic compounds (VOCs) and nitrogen dioxides (NOx), in addition to the other trace gases and particulate matter were measured at the National Reference Climatological Station (NRCS) (30.22° N, 120.17° E, 41.7 m a.s.l.) in urban Hangzhou. We found significant decreases in atmospheric PAN, NOx, the total VOCs, PM2.5, and sulfur dioxide (SO2) under the unfavorable meteorological condition during G20 (DG20) relative to the adjacent period before and after G20 (BG20 and AG20), indicating that the powerful control measures have taken into effect on reducing the pollutants emissions in Hangzhou. Unlike with the other pollutants, daily maximum average-8 h (DMA8) O3 exhibited a slight increase and then decrease from BG20 to AG20, which was mainly attributed to the variation in the solar irradiation intensity and regional transport besides the contribution from the implement of stringent control measures. Results from observation-based chemical model (OBM) indicated that acetaldehyde and methyl glyoxal (MGLY) were the most important second-generation precursors of PAN, accounting for 37.3–51.6 % and 22.8 %–29.5 % of the total production rates including the reactions of OVOCs, propagation of other radicals, and the other minor sources. Moreover, we confirmed the productions of PAN and O3 were both sensitive to VOCs throughout the whole period, specifically dominated by aromatics in BG20 and DG20 but alkenes in AG20. These findings suggested that reducing emissions of aromatics, alkenes, and alkanes would mitigate photochemical pollution including PAN and O3. Source appointment results attribute the reductions of VOCs source and ozone formation potentials (OFP) during G20 to the effective emission controls on traffic (vehicle exhaust) and industrial processes (solvent utilization and industrial manufacturing). However, fuel combustion and biogenic emission both weakened such effect with sizeable contribution on the VOCs mixing ratios (18.8 % and 20.9 %) and OFPs (25.6 % and 17.8 %), especially during the latter part of G20 (G20 II) when anthropogenic VOCs were substantially reduced. This study highlights the effectiveness of stringent emission controls in relation to traffic and industrial sources, but a coordinated program related with controlling fuel combustion and biogenic emissions is also required on addressing secondary pollution.

scholarly journals Changes in global air pollutant emissions during the COVID-19 pandemic: a dataset for atmospheric modeling

2021 ◽  
Vol 13 (8) ◽  
pp. 4191-4206 ◽  
Author(s):  
Thierno Doumbia ◽  
Claire Granier ◽  
Nellie Elguindi ◽  
Idir Bouarar ◽  
Sabine Darras ◽  
...  
Keyword(s):  
South America ◽  
Eastern China ◽  
Atmospheric Modeling ◽  
Air Pollutant ◽  
Control Measures ◽  
The Other ◽  
Atmospheric Pollutants ◽  
Pollutant Emissions ◽  
Adjustment Factors ◽  
The Impact

Abstract. In order to fight the spread of the global COVID-19 pandemic, most of the world's countries have taken control measures such as lockdowns during a few weeks to a few months. These lockdowns had significant impacts on economic and personal activities in many countries. Several studies using satellite and surface observations have reported important changes in the spatial and temporal distributions of atmospheric pollutants and greenhouse gases. Global and regional chemistry-transport model studies are being performed in order to analyze the impact of these lockdowns on the distribution of atmospheric compounds. These modeling studies aim at evaluating the impact of the regional lockdowns at the global scale. In order to provide input for the global and regional model simulations, a dataset providing adjustment factors (AFs) that can easily be applied to current global and regional emission inventories has been developed. This dataset provides, for the January–August 2020 period, gridded AFs at a 0.1×0.1 latitude–longitude degree resolution on a daily or monthly basis for the transportation (road, air and ship traffic), power generation, industry and residential sectors. The quantification of AFs is based on activity data collected from different databases and previously published studies. A range of AFs are provided at each grid point for model sensitivity studies. The emission AFs developed in this study are applied to the CAMS global inventory (CAMS-GLOB-ANT_v4.2_R1.1), and the changes in emissions of the main pollutants are discussed for different regions of the world and the first 6 months of 2020. Maximum decreases in the total emissions are found in February in eastern China, with an average reduction of 20 %–30 % in NOx, NMVOCs (non-methane volatile organic compounds) and SO2 relative to the reference emissions. In the other regions, the maximum changes occur in April, with average reductions of 20 %–30 % for NOx, NMVOCs and CO in Europe and North America and larger decreases (30 %–50 %) in South America. In India and African regions, NOx and NMVOC emissions are reduced on average by 15 %–30 %. For the other species, the maximum reductions are generally less than 15 %, except in South America, where large decreases in CO and BC (black carbon) are estimated. As discussed in the paper, reductions vary highly across regions and sectors due to the differences in the duration of the lockdowns before partial or complete recovery. The dataset providing a range of AFs (average and average ± standard deviation) is called CONFORM (COvid-19 adjustmeNt Factors fOR eMissions) (https://doi.org/10.25326/88; Doumbia et al., 2020). It is distributed by the Emissions of atmospheric Compounds and Compilation of Ancillary Data (ECCAD) database (https://eccad.aeris-data.fr/, last access: 23 August 2021).

scholarly journals Changes in global air pollutant emissions during the COVID-19 pandemic: a dataset for atmospheric chemistry modeling

2021 ◽  
Author(s):  
Thierno Doumbia ◽  
Claire Granier ◽  
Nellie Elguindi ◽  
Idir Bouarar ◽  
Sabine Darras ◽  
...  
Keyword(s):  
South America ◽  
Atmospheric Chemistry ◽  
Transport Model ◽  
Eastern China ◽  
Air Pollutant ◽  
Control Measures ◽  
Atmospheric Pollutants ◽  
Pollutant Emissions ◽  
The World ◽  
The Impact

Abstract. In order to fight the spread of the global COVID-19 pandemic, most of the world countries have taken control measures such as lockdowns during a few weeks to a few months. These lockdowns had significant impacts on economic and personal activities in many countries. Several studies using satellite and surface observations have reported important changes in the spatial and temporal distributions of atmospheric pollutants and greenhouse gases. Global and regional chemistry-transport model studies are being performed in order to analyze the impact of these lockdowns on the distribution of atmospheric compounds. These modeling studies aim at evaluating the impact of the regional lockdowns at the global scale. In order to provide input for the global and regional model simulations, a dataset providing adjustment factors (AFs) that can easily be applied to global and regional emission inventories has been developed. This dataset provides, for the January–August 2020 period, gridded AFs at a 0.1 × 0.1 latitude/longitude degree resolution, on a daily or monthly basis for the transportation (road, air and ship traffic), power generation, industry and residential sectors. The quantification of AFs is based on activity data collected from different databases and previously published studies. A range of AFs is provided at each grid point for model sensitivity studies. The emission AFs developed in this study are applied to the CAMS global inventory (CAMS-GLOB-ANT_v4.2_R1.1), and the changes in emissions of the main pollutants are discussed for different regions of the world and the first six months of 2020. Maximum decreases in the emissions are found in February in Eastern China, with an average reduction of 20–30 % in NOx, NMVOCs and SO2 relative to the reference emissions. In the other regions, the maximum changes occur in April, with average reductions of 20–30 % for NOx, NMVOCs and CO in Europe and North America and larger decreases (30–50 %) in South America. In India and African regions, NOx and NMVOCs emissions are reduced by 15–30 %. For the others species, the maximum reductions are generally less than 15 %, except in South America, where large decreases in CO and BC are estimated. As discussed in the paper, reductions vary highly across regions and sectors, due to the differences in the duration of the lockdowns before partial or complete recovery. The dataset providing a range of AFs (average and average ± standard deviation) is called CONFORM (COvid adjustmeNt Factor fOR eMissions) (https://doi.org/10.25326/88). It is distributed by the Emissions of atmospheric Compounds and Compilation of Ancillary Data (ECCAD) database (https://eccad.aeris-data.fr/).

Tolerance and Control. Developing a language policy for an EMI university in Uzbekistan

2020 ◽  
Vol 34 (1) ◽  
pp. 217-237
Author(s):  
Andrew Linn ◽  
Anastasiya Bezborodova ◽  
Saida Radjabzade
Keyword(s):  
Higher Education ◽  
Language Policy ◽  
Control Measures ◽  
The Other ◽  
Language Policies ◽  
Language Ecology ◽  
English Only ◽  
English Medium Instruction ◽  
The One ◽  
And Control

AbstractThis article presents a practical project to develop a language policy for an English-Medium-Instruction university in Uzbekistan. Although the university is de facto English-only, it presents a complex language ecology, which in turn has led to confusion and disagreement about language use on campus. The project team investigated the experience, views and attitudes of over a thousand people, including faculty, students, administrative and maintenance staff, in order to arrive at a proposed policy which would serve the whole community, based on the principle of tolerance and pragmatism. After outlining the relevant language and educational context and setting out the methods and approach of the underpinning research project, the article goes on to present the key findings. One of the striking findings was an appetite for control and regulation of language behaviours. Language policies in Higher Education invariably fall down at the implementation stage because of a lack of will to follow through on their principles and their specific guidelines. Language policy in international business on the other hand is characterised by a control stage invariably lacking in language planning in education. Uzbekistan is a polity used to control measures following from policy implementation. The article concludes by suggesting that Higher Education in Central Asia may stand a better chance of seeing through language policies around English-Medium Instruction than, for example, in northern Europe, based on the tension between tolerance on the one hand and control on the other.

scholarly journals The effects of energy paths and emission controls and standards on future trends in China's emissions of primary air pollutants

2014 ◽  
Vol 14 (17) ◽  
pp. 8849-8868 ◽  
Author(s):  
Y. Zhao ◽  
J. Zhang ◽  
C. P. Nielsen
Keyword(s):  
Air Pollutants ◽  
Control Strategies ◽  
Emission Control ◽  
Pollution Prevention ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Carbonaceous Aerosols ◽  
Emission Controls ◽  
Control Devices ◽  
Anthropogenic Pollutant

Abstract. To examine the efficacy of China's actions to control atmospheric pollution, three levels of growth of energy consumption and three levels of implementation of emission controls are estimated, generating a total of nine combined activity-emission control scenarios that are then used to estimate trends of national emissions of primary air pollutants through 2030. The emission control strategies are expected to have more effects than the energy paths on the future emission trends for all the concerned pollutants. As recently promulgated national action plans of air pollution prevention and control (NAPAPPC) are implemented, China's anthropogenic pollutant emissions should decline. For example, the emissions of SO2, NOx, total suspended particles (TSP), PM10, and PM2.5 are estimated to decline 7, 20, 41, 34, and 31% from 2010 to 2030, respectively, in the "best guess" scenario that includes national commitment of energy saving policy and implementation of NAPAPPC. Should the issued/proposed emission standards be fully achieved, a less likely scenario, annual emissions would be further reduced, ranging from 17 (for primary PM2.5) to 29% (for NOx) declines in 2015, and the analogue numbers would be 12 and 24% in 2030. The uncertainties of emission projections result mainly from the uncertain operational conditions of swiftly proliferating air pollutant control devices and lack of detailed information about emission control plans by region. The predicted emission trends by sector and chemical species raise concerns about current pollution control strategies: the potential for emissions abatement in key sectors may be declining due to the near saturation of emission control devices use; risks of ecosystem acidification could rise because emissions of alkaline base cations may be declining faster than those of SO2; and radiative forcing could rise because emissions of positive-forcing carbonaceous aerosols may decline more slowly than those of SO2 emissions and thereby concentrations of negative-forcing sulfate particles. Expanded control of emissions of fine particles and carbonaceous aerosols from small industrial and residential sources is recommended, and a more comprehensive emission control strategy targeting a wider range of pollutants (volatile organic compounds, NH3 and CO, etc.) and taking account of more diverse environmental impacts is also urgently needed.

scholarly journals Estimating the open biomass burning emissions in Central and Eastern China from 2003 to 2015 based on satellite observation

2018 ◽  
Author(s):  
Jian Wu ◽  
Shaofei Kong ◽  
Fangqi Wu ◽  
Yi Cheng ◽  
Shurui Zheng ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Annual Variation ◽  
Eastern China ◽  
Satellite Observation ◽  
Pollutant Emissions ◽  
Pollutant Emission ◽  
Burned Area ◽  
Management Policies ◽  
Straw Burning ◽  
Grassland Fire

Abstract. Open biomass burning (OBB) has significant impacts on air pollution, climate change and potential human health. OBB has raised wide attention but with few focus on the annual variation of pollutant emission. Central and Eastern China (CEC) is one of the most polluted regions in China. This study aims to provide a state-of the-art estimation of the pollutant emissions from OBB in CEC from 2003 to 2015, by adopting the satellite observation dataset (the burned area product (MCD64Al) and the active fire product (MCD14 ML)), local biomass data (updated biomass loading data and high-resolution vegetation data) and local emission factors. Monthly emissions of pollutants were estimated and allocated into a 1 × 1 km spatial grid for four types of OBB including grassland, shrubland, forest and cropland. From 2003 to 2015, the emissions from forest, shrubland and grassland fire burning had a minor annual variation whereas the emissions from crop straw burning steadily increased. The cumulative emissions of OC, EC, CH4, NOX, NMVOC, SO2, NH3, CO, CO2 and PM2.5 were 3.64 × 103, 2.87 × 102, 3.05 × 103, 1.82 × 103, 6.4 × 103, 2.12 × 102, 4.67 × 103, 4.59 × 104, 9.39 × 105 and 4.13 × 102 Gg in these years, respectively. For cropland, corn straw burning was the largest contributor for all pollutant emissions, by 84 %–96 %. Among the forest, shrubland, grassland fire burning, forest fire burning emissions contributed the most and emissions from grassland fire was negligible due to few grass coverage in this region. High pollutant emissions were populated in the connection area of Shandong, Henan, Jiangsu and Anhui, with emission intensity higher than 100 ton per pixel, which was related to the frequent agricultural activities in these regions. The monthly emission peak of pollutants occurred in summer and autumn harvest periods including May, June, September and October, at which period ~ 50 % of pollutants were emitted for OBB. This study highlights the importance in controlling the crops straw burning emission. From December to March of the next year, the crop residue burning emissions decreased, while the emissions from forest, shrubland and grassland exhibited their highest values, leading to another small peak emissions of pollutants. Obvious regional differences in seasonal variations of OBB were observed due to different local biomass types and environmental conditions. Rural population, agricultural output, local burning habits, anthropological activities and management policies are all influence factors for OBB emissions. The successful adoption of double satellite dataset for long term estimation of pollutants from OBB with a high spatial resolution can support the assessing of OBB on regional air-quality, especially for harvest periods or dry seasons. It is also useful to evaluate the effects of annual OBB management policies in different regions.

scholarly journals The Interdecadal Variations and Causes of the Relationship Between Autumn Precipitation Anomalies in Eastern China and SSTA Over the Southeastern Tropical Indian Ocean

2021 ◽  
Author(s):  
Liwei Huo ◽  
Zhaoyong Guan ◽  
Dachao Jin ◽  
Xi Liu ◽  
Xudong Wang ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Eastern China ◽  
Tropical Indian Ocean ◽  
The Other ◽  
Drought Event ◽  
Low Level ◽  
Rainfall Anomalies ◽  
Precipitation Anomalies ◽  
The Relationship ◽  
Southeastern Tropical Indian Ocean

Abstract Eastern China has a large population with rapid development of the economy, where is the important crop producing region. In this region, the spatial and temporal distribution of autumn rainfall in Eastern China is uneven, which has important societal impact. Using the NCEP–NCAR reanalysis and other observational datasets, it is found that the spatial distribution of the first EOF mode of autumn rainfall anomalies in eastern China is consistent across the region, with significant interannual variabilities. Pronounced interdecadal variations are presented in the relationship between autumn rainfall anomalies in eastern China and sea-surface temperature anomalies (SSTA) over the southeastern tropical Indian Ocean (SETIO). The interdecadal changes have been analyzed by considering two epochs: one during 1979-2004 and the other during 2005-2019. It shows weak and insignificant correlations between the autumn rainfall anomalies in eastern China and SSTA over SETIO during the first epoch. On the other hand, they are remarkable and positively correlated with each other during the second epoch. The inter-decadal changes of the above relationship are related to the warming of SST over SETIO during the second epoch. It causes stronger low-level convergence and ascending motion over SETIO, with the co-occurrence of enhanced western Pacific subtropical high and anomalous abundant moisture over eastern China carried by a low-level southerly anomaly originating from the South China Sea. Simultaneously, the local Hadley circulation over eastern China becomes weak, corresponding to the anomalous ascending motion. The collaboration of anomalous water vapour transport and ascending motion strengthens the connection between the SETIO SSTA and the autumn precipitation anomalies in eastern China, and vice versa. In the boreal autumn of 2019, entire eastern China suffered extreme drought. It suggests that this drought event in eastern China is strongly affected by the negative SSTA over SETIO, which is consistent with the statistical results.

scholarly journals A Critical Assessment on the Indonesian Free Visa Policy: a Neorealist Perspective

2020 ◽  
Vol 22 (1) ◽  
pp. 54
Author(s):  
Andry Indrady
Keyword(s):  
Public Perception ◽  
Economic Benefits ◽  
Critical Assessment ◽  
The State ◽  
Control Measures ◽  
The Other ◽  
Immigration Control ◽  
Other Hand ◽  
Visa Policy ◽  
The Ideal

This paper discusses the implementation of free visa policy in Indonesia from a neorealist perspective. By utilizing the perspective of interdependence sovereignty and domestic sovereignty, this paper critically assesses the implementation of the free visa policy in Indonesia. From the interdependence sovereignty perspective, which elaborates the economic benefits, reciprocal and security approaches the paper finds that the free visa policy in Indonesia has yet to formulate a rational and objective policy that would lead to potential security – order threat. On the other hand, from the domestic sovereignty perspective the paper finds that although the state performs its immigration control capabilities effectively, however the said immigration control measures are implemented at a rather repressive level, instead of at the ideal prevention level. In the end, the paper suggests further research that fills the gap from findings on the specific methods to enhance the state’s capability in managing challenges posed by the free visa policy in more detail, as well as providing a method to measure public perception on the performance of immigration control.

Sex and the Devil: Homosexuality, Satanism, and Moral Panic in Late Apartheid South Africa

2018 ◽  
Vol 22 (2) ◽  
pp. 273-293 ◽  
Author(s):  
Nicky Falkof
Keyword(s):  
South African ◽  
Moral Panic ◽  
White Male ◽  
White Men ◽  
Control Measures ◽  
The Other ◽  
Moral Panics ◽  
Sanitation And Hygiene ◽  
The Devil ◽  
Male Homosexuals

This article discusses the discursive and narrative intersections between two moral panics that appeared in the white South African press in the last years of apartheid: the first around the claimed danger posed by white male homosexuals, the second around the alleged incursion of a criminal cult of white Satanists. This connection was sometimes implicit, when the rhetoric attached to one was repeated with reference to the other, and sometimes explicit, when journalists and moral entrepreneurs conflated the two in public dialogue. Both Satanists and gay white men were characterized as indulging in abnormal practices that were dangerous to the health of the nation, using a long-standing colonial metaphor of sanitation and hygiene. I argue that fears of homosexuality and beliefs in Satanism operated as social control measures for disciplining potentially unruly groups whose sexual or personal practices were not admissible within apartheid’s injunctions on homogenous conformity among whites. The connection between homosexuality and Satanism, like the connection between homosexuality and communism, served to pathologize whites whose disobedient bodies and beliefs were considered treacherous.

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