LARGE-SCALE AIR POLLUTION MODELING IN EUROPE UNDER DIFFERENT CLIMATIC SCENARIOS

2019 ◽  
Vol 01 (02) ◽  
pp. 1950009 ◽  
Author(s):  
ZAHARI ZLATEV ◽  
IVAN DIMOV ◽  
ISTVÁN FARAGÓ ◽  
KRASSIMIR GEORGIEV ◽  
ÁGNES HAVASI

The treatment of large-scale air pollution models is not only important for modern society, but also an extremely difficult task. Five important physical and chemical processes: (1) horizontal advection, (2) horizontal diffusion, (3) vertical exchange, (4) emission of different pollutants and (5) dry and wet deposition have to be united and handled together. This leads to huge computational problems which have to be treated on modern high-speed parallel architectures by using advanced numerical methods. The computational difficulties are vastly increased when such models are used in the investigation of the impact of climatic changes on high pollution levels that are often exceeding certain critical concentrations and, therefore, are becoming harmful for plants, animals and human beings. There are two major reasons for the great increase in computational difficulties: (a) it is necessary to run the discretized data on fine spatial grid models over very long time-periods consisting of many consecutive years and (b) different scenarios are to be used in order to investigate the sensitivity of the pollution levels to systematic variations of several carefully selected key parameters. How the major difficulties can be resolved is explained here. Furthermore, many results are presented in order to demonstrate the ability of the model to handle successfully the huge computational tasks by using fine space and time discretization and by applying a chemical scheme with many chemical species participating in several hundred chemical reactions. Our results indicate that the climatic changes will often lead to some increases in the pollution levels.

2021 ◽  
Author(s):  
Zixuan Jia ◽  
Ruth Doherty ◽  
Carlos Ordóñez ◽  
Chaofan Li ◽  
Oliver Wild ◽  
...  

Abstract. The influence of large-scale circulation on daily PM2.5 variability through its direct effect on key regional meteorological variables is examined over three major populated regions of China: Beijing–Tianjin–Hebei (BTH), the Yangtze River Delta (YRD), and the Pearl River Delta (PRD). In BTH, a shallow East Asian trough curbs northerly cold and dry air from the Siberian High, enhancing PM2.5 pollution levels. Weak southerly winds in eastern and southern China, associated with a weakened Siberian High, suppress horizontal dispersion, contributing to air pollution accumulation over YRD. In PRD, weak southerly winds and precipitation deficits over southern China are conducive to high PM2.5 pollution levels. To account for these dominant large-scale circulation – PM2.5 relationships, we propose three new circulation-based indices for predicting different levels of air pollution based on regional PM2.5 concentrations in each region: a 500 hPa geopotential height-based index for BTH, a sea level pressure-based index for YRD and an 850 hPa meridional wind-based index for PRD. These three indices can effectively distinguish clean days from heavily polluted days in these regions, assuming variation is solely due to meteorology. We also find that including the most important regional meteorological variable in each region improves the performance of the circulation-based indices in predicting daily PM2.5 concentrations on the regional scale. These results are beneficial to understanding and forecasting the occurrence of heavily polluted PM2.5 days in BTH, YRD and PRD from a large-scale perspective.


2007 ◽  
Vol 23 (suppl 4) ◽  
pp. S529-S536 ◽  
Author(s):  
Izabel Marcilio ◽  
Nelson Gouveia

This study aimed to quantify air pollution impact on morbidity and mortality in the Brazilian urban population using locally generated impact factors. Concentration-response coefficients were used to estimate the number of hospitalizations and deaths attributable to air pollution in seven Brazilian cities. Poisson regression coefficients (beta) were obtained from time-series studies conducted in Brazil. The study included individuals 65 years old and over and children under five. More than 600 deaths a year from respiratory causes in the elderly and 47 in children were attributable to mean air pollution levels, corresponding to 4.9% and 5.5% of all deaths from respiratory causes in these age groups. More than 4,000 hospital admissions for respiratory conditions were also attributable to air pollution. These results quantitatively demonstrate the currently observed contribution of air pollution to mortality and hospitalizations in Brazilian cities. Such assessment is thought to help support the planning of surveillance and control activities for air pollution in these and similar areas.


2010 ◽  
Vol 10 (14) ◽  
pp. 6645-6660 ◽  
Author(s):  
P. Huszar ◽  
D. Cariolle ◽  
R. Paoli ◽  
T. Halenka ◽  
M. Belda ◽  
...  

Abstract. In general, regional and global chemistry transport models apply instantaneous mixing of emissions into the model's finest resolved scale. In case of a concentrated source, this could result in erroneous calculation of the evolution of both primary and secondary chemical species. Several studies discussed this issue in connection with emissions from ships and aircraft. In this study, we present an approach to deal with the non-linear effects during dispersion of NOx emissions from ships. It represents an adaptation of the original approach developed for aircraft NOx emissions, which uses an exhaust tracer to trace the amount of the emitted species in the plume and applies an effective reaction rate for the ozone production/destruction during the plume's dilution into the background air. In accordance with previous studies examining the impact of international shipping on the composition of the troposphere, we found that the contribution of ship induced surface NOx to the total reaches 90% over remote ocean and makes 10–30% near coastal regions. Due to ship emissions, surface ozone increases by up to 4–6 ppbv making 10% contribution to the surface ozone budget. When applying the ship plume parameterization, we show that the large scale NOx decreases and the ship NOx contribution is reduced by up to 20–25%. A similar decrease was found in the case of O3. The plume parameterization suppressed the ship induced ozone production by 15–30% over large areas of the studied region. To evaluate the presented parameterization, nitrogen monoxide measurements over the English Channel were compared with modeled values and it was found that after activating the parameterization the model accuracy increases.


2020 ◽  
Vol 1 (2) ◽  
pp. 120-131
Author(s):  
Indra Budi Jaya

Islam as a religion wants its people to always maintain a balance between religiosity (al din) and worldly problems (al dunya). The relationship between the two describes something that is separate but inseparable (harmony). However, for modern society, this condition often creates contradictions, this condition was seen at the time of the Covid 19 pandemic. The implementation of Large-Scale Social Restrictions by the government in an effort to overcome the spread of the impact of Covid 19 to the community by limiting activities in mosques and allowing activities in the market to continue in fact responded by the community differently. The methodology used is qualitative by using social policy analysis. This paper tries to examine social policies towards the application of large-scale social restrictions on mosques and markets. In this paper, the sociology of law theory is used, namely Law is a social engineering tool which emphasizes that law becomes the commander who must bring change to society. The results obtained in the research are that the community responds to the large-scale social restriction policy differently, where the purpose of the policy is for the community to be expected to make changes by complying with the rules that have been set by the government, the conditions for rejection and various responses are caused by disharmony between implementation of policies with public awareness of the law.Keyword : Policy, large-Scale Restrictions and the sociology of law. AbstrakIslam sebagai agama mengkhendaki umatnya agar senantiasa menjaga keseimbangan antara religiusitas (al din) dan masalah keduniaan (al dunia). Hubungan keduanya menggambarkan sesuatu yang terpisah namun tidak bisa dipisahkan (harmoni). Namun bagi masyarakat modern kondisi tersebut seringkali justru menimbulkan pertentangan, kondisi tersebut nampak pada saat terjadinya pandemi Covid 19. Penerapan Pembatasan Sosial Berskala Besar oleh pemerintah dalam upaya penanggulangan penyebaran dampak Covid 19 kepada masyarakat dengan membatasi aktivitas di masjid dan membiarkan kegiatan di pasar tetap berjalan nyatanya direspon oleh masyarakat secara berbeda. Metodologi yang digunakan adalah kualitatif dengan menggunakan analisis kebijakan sosial, Tulisan ini mencoba menelaah kebijakan sosial terhadap penerapan pembatasan sosial berskala besar terhadap masjid dan pasar. Dalam penulisan ini dipergunakan teori sosiologi hukum yaitu Law is a tool social engineering yang menegaskan bahwa hukum menjadi panglima yang harus membawa perubahan terhadap masyarakat. Hasil yang diperoleh dalam penelitian adalah Masyarakat merespon kebijakan pembatasan sosial berskala besar tersebut secara berbeda, dimana tujuan kebijakan tersebut adalah untuk masyarakat diharapkan dapat melakukan perubahan dengan mematuhi aturan yang telah di tetapkan oleh pemerintah, kondisi penolakan dan respon beragam tersebut di sebabkan oleh ketidak harmonisannya antara penerapan kebijakan dengan kesadaran masyarakat terhadap hukum.Kata Kunci : Kebijakan,  Pembatasan Sosial Berskala Besar dan Sosiologi Hukum


2021 ◽  
pp. 1-34
Author(s):  
YONGBO GE ◽  
YUEXIAO ZHU ◽  
WENQIANG ZHANG ◽  
XIAORAN KONG

We investigate the impact of the construction of large-scale high-speed railways (HSRs) on regional multidimensional poverty in China. We find that the opening of HSRs can reduce this poverty indicator. This association is robust to a series of checks. Regarding the mechanisms, the opening of HSRs can improve regional accessibility, enhance local tourism, increase labor mobility and promote human capital accumulation, which alleviates multidimensional poverty. Further research indicates the regional heterogeneity of the effect. This research supplements poverty alleviation theory from the perspective of public infrastructure and offers insight into how multidimensional poverty arises and how it can be alleviated.


Author(s):  
Ting Yu ◽  
Tushar Chaitanya

MV (Medium Voltage) controller lineup electrical protection is crucial in protecting the equipment from large scale damage upon the occurrence of an electrical fault, reducing the time to restore power, thereby minimizing the impact to liquids pipelines operation. The paper discusses typical electrical failure modes that may occur in MV controller lineups, and demonstrates practical relaying engineering techniques that enable fast and effective fault clearing. Electrical faults in the MV controller lineup are often arcing type, commonly involve ground. Mitigating arc hazards in MV Class E2 controller lineups has traditionally been challenging without sacrificing the protection selectivity. As the paper demonstrates, a relaying scheme with the combined use of high-speed light-sensing and overcurrent detection will effectively mitigate the incident energy, while maintaining the protection selectivity for non-arcing overcurrent events. For new MV controller lineups, in addition to the “high-speed light detection and fault interruption”, zone-selective interlocking (ZSI) can also be a practical solution in improving relay protection speed, thus reduce the chance of severe arc flash occurrences. ZSI is particularly effective for fault occurrences on the line side of the phase CTs, busways or main incoming circuits. The ZSI scheme can be implemented on both Class E2 and circuit breaker (VCB) type MV controller lineups, however, with slightly different trip logic due to the limited fault clearing capability of the contactor. Although there are multiple contributing factors, the direct causes of electrical failures in MV controller lineup are commonly related to improper power cable installation and handling, potentially leading to premature insulation breakdown due mainly to the proximity effect and/or partial discharge. Inadequate cable separation and prolonged fault trip delay can increase the possibility of arcing fault occurrence. This can usually be mitigated through appropriate cable spacing, adequate conductor insulation, and optimized fault detection schemes. The paper provides overviews of the mechanisms of proximity effect and partial discharge propagation, and the modern relaying approaches for accurate fault type discrimination and facilitating fast fault interruption. Two case studies are provided in the paper as an aid in understanding the electrical fault mechanism originated from cable insulation failure, demonstrating the incident energy reduction before and after the implementation of high-speed light detection and fault interruption solutions on an existing MV controller lineup.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Jing Zuo ◽  
Jianwu Dang ◽  
Min Lyu

In large-scale high-speed rail networks (HSRNs), the occurrence of occasional malfunctions or accidents is unavoidable. The key issue considered in this study is the optimal allocation of the maintenance costs, based on the stochastic risk assessment for HSRNs. Inspired by the theoretical risk evaluation methods in the complex network, three major factors, including the local effects, global effects, and component self-effects are considered in the process of assessing the impact on the network components (nodes or lines). By introducing the component failure occurrence probability, which is considered to be an exponential function changing with the component maintenance costs, a feasible stochastic risk assessment model of the HSRNs together with the component impact assessment is proposed that can better unify the impact assessment of both the high-speed rail stations and railways. An optimal allocation algorithm based on a Lagrangian relaxation approach is designed. Correspondingly, the optimal cost allocation scheme can be determined using the algorithm to eliminate the various HSRN risks under the given costs. Furthermore, a real-world case study of the HSRNs in eastern China is illustrated. Compared with the genetic algorithm, the simulation shows that the approach can solve the optimal cost allocation problem to more effectively reduce the risks of large-scale HSRNs in practice.


2012 ◽  
Vol 12 (19) ◽  
pp. 9335-9353 ◽  
Author(s):  
H. G. Ouwersloot ◽  
J. Vilà-Guerau de Arellano ◽  
A. C. Nölscher ◽  
M. C. Krol ◽  
L. N. Ganzeveld ◽  
...  

Abstract. We studied the atmospheric boundary layer (ABL) dynamics and the impact on atmospheric chemistry during the HUMPPA-COPEC-2010 campaign. We used vertical profiles of potential temperature and specific moisture, obtained from 132 radio soundings, to determine the main boundary layer characteristics during the campaign. We propose a classification according to several main ABL prototypes. Further, we performed a case study of a single day, focusing on the convective boundary layer, to analyse the influence of the dynamics on the chemical evolution of the ABL. We used a mixed layer model, initialized and constrained by observations. In particular, we investigated the role of large scale atmospheric dynamics (subsidence and advection) on the ABL development and the evolution of chemical species concentrations. We find that, if the large scale forcings are taken into account, the ABL dynamics are represented satisfactorily. Subsequently, we studied the impact of mixing with a residual layer aloft during the morning transition on atmospheric chemistry. The time evolution of NOx and O3 concentrations, including morning peaks, can be explained and accurately simulated by incorporating the transition of the ABL dynamics from night to day. We demonstrate the importance of the ABL height evolution for the representation of atmospheric chemistry. Our findings underscore the need to couple the dynamics and chemistry at different spatial scales (from turbulence to mesoscale) in chemistry-transport models and in the interpretation of observational data.


2020 ◽  
Author(s):  
Elie Dhivert ◽  
François Gibon ◽  
Karine Hochart ◽  
Bertrand Devillers

<p>In application of the EU Water Framework Directive, many actions have been undertaken in order to reduce pollution levels in river systems. However, for certain catchments, the resilience process is not occurring as expected. In the Bienne River basin, metals discharge has plummeted since the 1990s, following the implementation of a better industrial waste management, as well as an important industrial restructuring. Nevertheless, this river has been regularly affected by massive fish mortality over the 2012-2019 period. This phenomenon, never identified before, is becoming recurrent. Organic tissues sampled in dead fish contained high concentrations of metals in association with other toxics. In this context, this study introduces a transdisciplinary approach in order to: (i) analyse spatial and temporal evolutions of pollutions in the Bienne River, (ii) evaluate potential ecotoxicological impacts associated, (iii) identify interactions with local hydro-climatic changes. Metallic and organic pollutants were analysed over different stations and at multi-temporal scales, associating sedimentary archives, suspended matters and passive water samplers. These analyses highlight the impact on the river quality of both current and legacy pollutions, particularly during prolonged low-water periods and high discharge events. Ecotoxicological analyses emphasize a severe risk level in the case of polluted sediments remobilization, especially because of heavy metals and PAH contamination. Geochemical evidence of such remobilization events has been recorded over the last decade in a sedimentary core sampled in the downstream part of the Bienne River. Hydrological data recorded in the Bienne River gauging stations since 1971 attests of an important year-to-year variability, although changes in the river discharge distribution are ongoing. Data has shown a higher frequency of both the lowest and the highest outflows over the 2012-2019 period compared to the rest of the hydrological recording. Hydro-climatic variables coming from in-situ measurements and satellite data (GPM-IMERG6) has also shown significant modifications in the rainfall regime over this period, especially in the augmentation of dry spells and heavy rainfall episodes. Those modifications agree well with the discharge change observations. This study brings out knock-on impacts of combined geochemical, ecotoxicological and hydro-sedimentary issues on the fate of aquatic ecosystems, especially under the influence of local hydro-climatic changes and their implications on hydrological regimes. Those results aim at reducing uncertainties concerning the evolution of the river quality by highlighting such a tipping point for environmental conditions. In addition, such a study helps us to grasp the complexity of local stakes regarding the multiple interests of a wide range of stakeholders and policy makers involved on the field.</p>


2017 ◽  
Vol 2634 (1) ◽  
pp. 101-109 ◽  
Author(s):  
Weibo Li ◽  
Maria Kamargianni

A modal shift from motorized to nonmotorized vehicles is imperative to reduce air pollution in developing countries. Nevertheless, whether better air quality will improve the willingness to use nonmotorized transport remains unclear. If such a reciprocal effect could be identified, a sort of virtuous circle could be created (i.e., better air quality could result in higher nonmotorized transport demand, which in turn could further reduce air pollution). Developing countries may, therefore, be more incentivized to work on air pollution reduction from other sources to exploit the extra gains in urban transport. This study investigated the impact of air pollution on mode choices and whether nonmotorized transport was preferred when air quality was better. Revealed preference data about the mode choice behavior of the same individuals was collected during two seasons (summer and winter) with different air pollution levels. Two discrete mode choice models were developed (one for each season) to quantify and compare the impacts of different air pollution levels on mode choices. Trip and socioeconomic characteristics also were included in the model to identify changes in their impacts across seasons. Taiyuan, a Chinese city that operates a successful bikesharing scheme, was selected for a case study. The study results showed that air quality improvement had a significant, positive impact on nonmotorized transport use, which suggested that improvements in air quality and promotion of nonmotorized transport must be undertaken simultaneously because of their interdependence. The results of the study could act as a harbinger to policy makers and encourage them to design measures and policies that lead to sustainable travel behavior.


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