Marked long-term decline in ambient CO mixing ratio in SE England, 1997–2014:Evidence of policy success in improving air quality

Atmospheric CO at Egham in SE England has shown a marked and progressive decline since 1997, following adoption of strict controls on emissions. The Egham site is uniquely positioned to allow both assessment and comparison of ‘clean Atlantic background’ air and CO-enriched air downwind from the London conurbation. The decline is strongest (approximately 50ppb per year) in the 1997–2003 period but continues post 2003. A ‘local CO increment’ can be identified as the residual after subtraction of contemporary background Atlantic CO mixing ratios from measured values at Egham. This increment, which is primarily from regional sources (during anticyclonic or northerly winds) or from the European continent (with easterly air mass origins), has significant seasonality, but overall has declined steadily since 1997. On many days of the year CO measured at Egham is now not far above Atlantic background levels measured at Mace Head (Ireland). The results are consistent with MOPITT satellite observations and ‘bottom-up’ inventory results. Comparison with urban and regional background CO mixing ratios in Hong Kong demonstrates the importance of regional, as opposed to local reduction of CO emission. The Egham record implies that controls on emissions subsequent to legislation have been extremely successful in the UK

The influence of street layouts and viaduct settings on daily carbon monoxide exposure and intake fraction in idealized urban canyons

Environmental concerns have been raised on the adverse health effects of vehicle emissions in micro-scale traffic-crowded street canyons, especially for pedestrians and residents living in near-road buildings. Viaduct design is sometimes used to improve transportation efficiency but possibly affects urban airflow and the resultant exposure risk, which have been rarely investigated so far. The personal intake fraction (P_IF) is defined as the average fraction of total emissions that is inhaled by each person of a population (1ppm=1×10-6), and the daily carbon monoxide (CO ) pollutant exposure (Et) is estimated by multiplying the average concentration of a specific micro-environment within one day. As a novelty, by considering time activity patterns and breathing rates in various micro-environments for three age groups, this paper introduces IF and Et into computational fluid dynamic (CFD) simulation to quantify the impacts of street layouts (street width/ building height W/H=1, 1.5, 2), source location, viaduct settings and noise barriers on the source-exposure correlation when realistic CO sources are defined. Narrower streets experience larger P_IF (1.51-5.21 ppm) and CO exposure, and leeward-side buildings always attain higher vehicular pollutant exposure than windward-side. Cases with a viaduct experience smaller P_IF (3.25-1.46 ppm) than cases without a viaduct (P_IF=5.21-2.23 ppm) if the single ground-level CO source is elevated onto the viaduct. With two CO sources (both ground-level and viaduct-level), daily CO exposure rises 2.80-3.33 times but P_IF only change slightly. Noise barriers above a viaduct raise concentration between barriers, but slightly reduce vehicular exposure in near-road buildings. Because people spend most of their time indoors, vehicular pollutant exposure within near-road buildings can be 6-9 times that at pedestrian level. Although further studies are still required to provide practical guidelines, this paper provides effective methodologies to quantify the impacts of street/viaduct configurations on human exposure for urban design purpose

Air emissions from ships in port : Does regulation make a difference?

Vessel operations at port play a particular role in port-related air emissions. Hotelling, manoeuvring and cruising operations in the harbour areas generate a large share of local and global pollution, external costs and public health issues. Emission abatement demands effective regulation for vessel compliance and enforcement adequacy in despite of geographic differences in jurisdiction. A connecting relation between regulatory frameworks and atmospheric pollution from vessels operations at port is so far, missing in literature. This paper aims at filling in this gap by addressing exhaust gasses (NOx, SOx, CO, CO2) and particles (PM2.5) released from operative vessels in port with differing regulatory frameworks (Las Palmas, St. Petersburg, and Hong Kong). Estimations are based on the Ship Traffic Emission Assessment Model (STEAM) and AIS traffic information over a twelve-month timeframe. Contribution of this paper relates to revealing emission patterns of vessel operations in port and the assessment of current regulatory frameworks. Results and lower emission profiles shed light to sulphur regulation differences and the potential benefits in new policy measures (polluter pays principle, cold ironing and others) of accounting operative modes and shipping sub-sectors.Peer reviewe

Local air quality management and health impacts of air pollution in Thailand

Air quality in urban areas of Chiang Mai Province, Thailand has seriously deteriorated as a consequence of population growth and urbanization and due to a lack of effective air quality management (AQM). As a result, respiratory diseases among Chiang Mai residents have increased in these affected areas. The health status and experiences of air pollution of both children and adults in Chiang Mai was assessed and improvements recommended to the developing AQM scheme. Air quality modelling, using ADMS-Urban was used to identify probable air polluted and control sites for further study. The polluted sites were found to be located along major roads in the city. However, ADMS-Urban was unable to predict air pollutant concentrations accurately because it could not cope with the very low wind speeds and complex topography of Chiang Mai. As a result, the utility of other air pollution modelling programmes should be investigated. The results of a questionnaire survey conducted with adults showed that urban respondents had a higher percentage of respiratory diseases than suburban respondents. However, later investigations were unable to establish a statistical linkage between air pollution concentrations and respiratory diseases. An ISAAC study was conducted among children attending schools located in the selected sites to assess the potential impacts of air pollution on health. The results showed that the prevalence of asthma was similar in all of the schools (approximately 5%) but that the prevalence of rhinitis (24.3% vs. 15.7%) and atopic dermatitis (12.5% vs. 7.2%) was higher in the urban schools which were considered to be more polluted. Logistic regression analysis identified other factors which may be involved in addition to pollution, including some components of the diet and contact with animals. In order to investigate the adequacy of the AQM system in Thailand, a comparative study was conducted between Hong Kong and Thailand. Both countries were investigated with respect to conformance to Good Urban Governance. The comparison showed that there are significant differences between the two countries and the AQM system in Hong Kong was more highly developed. For example, in contrast to the system in Hong Kong, it was found that there was insufficient involvement of the population in the development and implementation of AQM systems in Thailand. In order to better understand the reasons why the AQM system in Thailand is poor at both the provincial and local levels in Chiang Mai, prioritisation of AQM was assessed for major national environmental policies and plans; at the provincial level, fund allocations to development projects were reviewed; and at the sub-district level; a questionnaire survey was conducted among local government officials. It was concluded that AQM was not given sufficiently high priority in national plans and was generally ineffective and that, due to the non-specific nature of guidelines and frameworks in these plans, it was difficult for government organizations at the lower levels to establish AQM action plans for effective implementation. A range of appropriate measures to improve air quality in Chiang Mai were recommended. These included a more effective management of air pollution, an identified need for training and major changes in the transport system in the city

Climate and more sustainable cities: climate information for improved planning and management of cities (producers/capabilities perspective)

In the last two decades substantial advances have been made in the understanding of the scientific basis of urban climates. These are reviewed here with attention to sustainability of cities, applications that use climate information, and scientific understanding in relation to measurements and modelling. Consideration is given from street (micro) scale to neighbourhood (local) to city and region (meso) scale. Those areas where improvements are needed in the next decade to ensure more sustainable cities are identified. High-priority recommendations are made in the following six strategic areas: observations, data, understanding, modelling, tools and education. These include the need for more operational urban measurement stations and networks; for an international data archive to aid translation of research findings into design tools, along with guidelines for different climate zones and land uses; to develop methods to analyse atmospheric data measured above complex urban surfaces; to improve short-range, high-resolution numerical prediction of weather, air quality and chemical dispersion through improved modelling of the biogeophysical features of the urban land surface; to improve education about urban meteorology; and to encourage communication across scientific disciplines at a range of spatial and temporal scales

Quantification of the effect of both technical and non-technical measures from road transport on Spain's emissions projections

Atmospheric emissions from road transport have increased all around the world since 1990 more rapidly than from other pollution sources. Moreover, they contribute to more than 25% of total emissions in the majority of the European Countries. This situation confirms the importance of road transport when complying with emission ceilings (e.g. Kyoto Protocol and National Emissions Ceilings Directive). A methodology has been developed to evaluate the effect of transport measures on atmospheric emissions (EmiTRANS). Its application to Spain in the horizon of 2020 allows the quantification of the effect of several measures on emission reductions. This quantification was done through scenario development. Several scenarios were calculated considering technical measures (e.g. vehicle scrapping systems, higher penetration of hybrid and electric vehicles, fuel substitution, etc.) and non-technical measures (mileage reduction, implementation of Low Emission Zones and/or Congestion Charges in main cities, reduction of average speeds, logistical improvements that affects heavy duty vehicle load factors, etc.). The scenarios show the effect of each measure on NOx, SO2, CO, PM10, PM2.5, VOC, CO2 and CH4 emissions. The main conclusion is the necessity to combine both technical and non-technical measures to increase global effectiveness. In the analysis of specific pollutants, there is a great dispersion on reductions effect: technical measures are more effective to reduce air pollutants while non-technical measures are better options to reduce greenhouse effect gases (even though they also reduce air pollutants in a less efficient way)

Estratégias de apoio para melhorar a qualidade do ar em áreas portuárias

Despite their key contribution to economic development, harbours pose environmental threat, affecting air quality, local climate, and human health, due to the release of several pollutants. Poor local air quality episodes are particularly concerning when harbours are located near densely populated urban areas, threatening inhabitants’ health. This Thesis was focused on the assessment of the impact of harbour emissions on the air quality over harbours and their surrounding urban areas, with a final goal of producing guidelines to support decision-making in the harbour sector and air quality management, using Port of Leixões as a case-study. After reviewing the state-of-the-art in this research field, a high-resolution emission inventory was developed, based on the two most used methodologies within the scientific community. Data about ship and cargo handling equipment were compiled, allowing the quantification of emissions and identification of their main sources. The comparison of the two methodologies indicates that a new harmonized methodology is recommended, besides the need of continuous update of emission factors and activity data. Having the detailed emission inventory, the community-scale webtool C-PORT was applied for the first time in European harbours to simulate the impact of the maritime emissions on local air quality. The comparison of modelled and observed values validated its application for the case study of Port of Leixões. The highest PM10 concentrations were found near the South Container Terminal of Port of Leixões, while NOx concentrations above 100 µg/m3 were also found near the highway. Land-based emission sources exhibited the highest contribution (around 80 %) to the PM10 concentrations in the study area, while 50 % of NOx concentration was due to docked ships. Mitigation measures were investigated and assessed to improve air quality in harbours and their surroundings. In a case-study, pollutant dispersion was addressed, aiming to control fugitive petcoke emissions and their impact on Port of Aveiro’s neighbour communities. Optimal structure, size and position of a physical barrier were defined based on numerical and physical modelling, achieving a maximum reduction in petcoke dust reaching the nearby residential area of 74 – 88 % for the most frequent/critical wind directions. The studied barrier has been implemented in the field and monitoring campaigns are currently being carried out to assess its effectiveness.Apesar do seu papel-chave no desenvolvimento económico, os portos marítimos constituem uma ameaça ambiental, com impactes na qualidade do ar, clima local, e saúde humana, devido à emissão de inúmeros poluentes. Episódios de má qualidade do ar a nível local são particularmente preocupantes no caso de portos localizados nas imediações de áreas urbanas densamente povoadas, pondo em risco a saúde dos habitantes locais. Esta Tese focou-se no impacte das emissões portuárias na qualidade do ar em portos e suas vizinhanças urbanas. O objetivo final foi a produção de recomendações de suporte à tomada de decisão no setor portuário e gestão da qualidade do ar, usando o Porto de Leixões como caso-de-estudo. Após uma revisão do estado-da-arte neste campo, foi desenvolvido um inventário de emissões de alta-resolução, aplicando as duas metodologias mais frequentemente usadas na comunidade científica. Foram compilados dados sobre navios e equipamentos portuários, permitindo a quantificação das emissões e identificação das suas fontes maioritárias. Deste procedimento resultaram recomendações sobre o desenvolvimento de uma nova metodologia harmonizada. Ficou ainda evidenciada a relevância da atualização dos fatores de emissão e dos dados disponíveis sobre as diferentes atividades portuárias. Dispondo deste inventário de emissões, o C-PORT, uma ferramenta web de escala comunitária, foi aplicado pela primeira vez em portos europeus, para simular o impacte das emissões marítimas na qualidade do ar local. A comparação dos valores modelados com medições de campo validou a aplicação desta ferramenta ao caso-de-estudo do Porto de Leixões. A concentração mais elevada de PM10 foi registada no Terminal de Contentores Sul, registando-se também elevada (> 100 µg/m3 ) concentração de NOx junto à autoestrada vizinha. A maior contribuição (cerca de 80 %) para a emissão global de PM10 na área de estudo adveio de fontes de emissão terrestres, enquanto os navios atracados contribuíram com cerca de 50 % das emissões de NOx. Esta Tese inclui a análise de medidas de mitigação capazes de melhorar a qualidade do ar em portos marítimos e sua vizinhança. O caso-de-estudo apresentado foca-se na dispersão de poluentes, com o intuito de controlar a emissão de partículas de petcoke do Porto de Aveiro, e o seu impacte nas comunidades vizinhas. Com esse objetivo, foi estudada, através de simulação física e numérica, a composição, dimensão e posicionamento de uma barreira física. A solução otimizada permitiu reduzir em 74 % – 88 % para as direções de vento mais frequentes/críticas nesta região, estando atualmente implementada no terreno.Programa Doutoral em Ciências e Engenharia do Ambient