some remarks about a community open source lagrangian pollutant transport and dispersion model

Nowadays fishes and mussels farming is very important, from an economical point of view, for the local social background of the Bay of Naples. Hence, the accurate forecast of marine pollution becomes crucial to have reliable evaluation of its adverse effects on coastal inhabitants' health. The use of connected smart devices for monitoring the sea water pollution is getting harder because of the saline environment, the network availability and the maintain and calibration costs2. To this purpose, we designed and implemented WaComM (Water Community Model), a community open source model for sea pollutants transport and dispersion. WaComM is a model component of a scientific workflow which allows to perform, on a dedicated computational infrastructure, numerical simulations providing spatial and temporal high-resolution predictions of weather and marine conditions of the Bay of Naples leveraging on the cloud based31FACE-IT workflow engine27. In this paper we present some remarks about the development of WaComM, using hierarchical parallelism which implies distributed memory, shared memory and GPGPUs. Some numerical details are also discussed. Peer-review under responsibility of the Conference Program Chairs

Atmospheric dispersion modelling of particulate and gaseous pollutants affecting the trans-Manche region

This thesis describes the development of a methodology to determine large-scale and meso-scale atmospheric dispersion patterns. The research is only concerned with outdoor exposure to atmospheric pollutants and aims to identify pollution sources using dispersion modelling with the assistance of ground level measurements from British, French and other monitoring stations and remote sensing technology. Lagrangian Particle Dispersion (LPD) models compute trajectories of a large number of notional particles and can be used to numerically simulate the dispersion of a pollutant (passive tracer) in the planetary boundary layer. Two widely used atmospheric dispersion models were employed: the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model by R. Draxler, and the model FLEXPART by Stohl et al. Both models possess forward tracking and inverse (or receptor-based) modes. Meteorological data output from the PSU/NCAR Mesoscale model (known as MM5), or datasets from the European Centre of Medium-range Weather Forecast (ECMWF) are used to drive the dispersion models. Linkage routines were developed to interpret the LPD codes with the required meteorological information. This study aims to determine whether current approaches and practice for atmospheric dispersion modelling are reliable, consistent and up-to-date. An intercomparison of the models FLEXPART and HYSPLIT is performed for known episodes to determine their accuracy, ease of use, effect of source specification and to investigate their sensitivity to input data and mesh resolution, and in particular the effect of different model formulations and assumptions followed by the models. The possibility of identifying emission sources in the near and far field is investigated, by modelling dispersion backwards in time, in particular the discrimination of multiple sources from receptor data is discussed. The effect of meteorological data resolution on the output of LPD models was evaluated and the most suitable methodology for better source definition was determined for different modelling scales, ranging from the intercontinental transport of airborne pollutants to simulating pollution episodes caused by local sources

Participatory Roles of Urban Trees in Regulating Environmental Quality

abstract: The world has been continuously urbanized and is currently accommodating more than half of the human population. Despite that cities cover only less than 3% of the Earth’s land surface area, they emerged as hotspots of anthropogenic activities. The drastic land use changes, complex three-dimensional urban terrain, and anthropogenic heat emissions alter the transport of mass, heat, and momentum, especially within the urban canopy layer. As a result, cities are confronting numerous environmental challenges such as exacerbated heat stress, frequent air pollution episodes, degraded water quality, increased energy consumption and water use, etc. Green infrastructure, in particular, the use of trees, has been proved as an effective means to improve urban environmental quality in existing research. However, quantitative evaluations of the efficacy of urban trees in regulating air quality and thermal environment are impeded by the limited temporal and spatial scales in field measurements and the deficiency in numerical models. This dissertation aims to advance the simulation of realistic functions of urban trees in both microscale and mesoscale numerical models, and to systematically evaluate the cooling capacity of urban trees under thermal extremes. A coupled large-eddy simulation–Lagrangian stochastic modeling framework is developed for the complex urban environment and is used to evaluate the impact of urban trees on traffic-emitted pollutants. Results show that the model is robust for capturing the dispersion of urban air pollutants and how strategically implemented urban trees can reduce vehicle-emitted pollution. To evaluate the impact of urban trees on the thermal environment, the radiative shading effect of trees are incorporated into the integrated Weather Research and Forecasting model. The mesoscale model is used to simulate shade trees over the contiguous United States, suggesting how the efficacy of urban trees depends on geographical and climatic conditions. The cooling capacity of urban trees and its response to thermal extremes are then quantified for major metropolitans in the United States based on remotely sensed data. It is found the nonlinear temperature dependence of the cooling capacity remarkably resembles the thermodynamic liquid-water–vapor equilibrium. The findings in this dissertation are informative to evaluating and implementing urban trees, and green infrastructure in large, as an important urban planning strategy to cope with emergent global environmental changes.Dissertation/ThesisDoctoral Dissertation Civil, Environmental and Sustainable Engineering 201

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

The Atmospheric Effects of Stratospheric Aircraft: a First Program Report

Studies have indicated that, with sufficient technology development, high speed civil transport aircraft could be economically competitive with long haul subsonic aircraft. However, uncertainty about atmospheric pollution, along with community noise and sonic boom, continues to be a major concern; and this is addressed in the planned 6 yr HSRP begun in 1990. Building on NASA's research in atmospheric science and emissions reduction, the AESA studies particularly emphasizing stratospheric ozone effects. Because it will not be possible to directly measure the impact of an HSCT aircraft fleet on the atmosphere, the only means of assessment will be prediction. The process of establishing credibility for the predicted effects will likely be complex and involve continued model development and testing against climatological patterns. Lab simulation of heterogeneous chemistry and other effects will continue to be used to improve the current models

Modelação multiescala de qualidade do ar urbana para cidades mais saudáveis

Ambient air pollution is nowadays a serious public health problem worldwide, especially in urban areas due to high population density and intense anthropogenic activity. Among the main urban air pollution sources, the road traffic sector is one of the major concerns and the largest contributor to nitrogen dioxide (NO2) concentrations, though regional background chemical conditions must also be considered. In this context, the use of modelling tools is crucial to understand atmospheric and social dynamics in multiple scales, as well as to support in defining the best air quality improvement strategies. The main objective of this thesis is to develop and apply a multiscale modelling system able to simulate air quality and health impacts in cities. For this purpose, the modair4health multiscale air quality and health risk modelling system was developed and operationalized. It includes the online model WRF-Chem, which provides air quality and meteorological fields from regional to urban scales, and the Computational Fluid Dynamics (CFD) model VADIS, which uses the urban WRF-Chem outputs to calculate flows and dispersion of traffic emissions-related air pollutants in urban built-up areas. A health module, based on linear and non-linear World Health Organization approaches, was also integrated in modair4health to assess the health impacts resulting from air quality changes, and the overall health damage costs are calculated based on economic studies. The application and assessment of the modair4health system allowed to identify the most appropriate configurations and input data, which were used to apply the system over the case study testing air quality improvement scenarios. One of the busiest road traffic areas of the city of Coimbra (Fernão de Magalhães Avenue) in Portugal was selected as case study. The application considered a 4 domains setup: three nested domains (25, 5 and 1 km2 resolutions) for the WRF-Chem, and the 4th domain (4 m2 resolution) over the target local study area and NO2 for the VADIS. WRF-Chem was applied along the year 2015 and VADIS was simulating two particular periods: one week in winter and another one in summer. Short-term health impacts were estimated and the non-linear approach led to lower health outcomes that seem better adjusted to the local reality. Finally, to assess the modair4health capabilities for decision-making support, two traffic management scenarios were tested over the case study: replacement of 50% of the vehicle fleet below EURO 4 by electric vehicles (ELEC), and introduction of a Low Emission Zone (LEZ). Air quality and health positive impacts were higher for the ELEC scenario. This study represents a scientific advance in multiscale air quality and health modelling. The modair4health system can be easily adapted and applied to other simulation domains, providing urban air pollution levels and subsequent health impacts for different case studies and supporting the assessment of air pollution control policies.A poluição atmosférica é atualmente um sério problema mundial de saúde pública, especialmente em áreas urbanas, devido à elevada densidade populacional e intensa atividade antropogénica. O setor dos transportes rodoviários é uma das principais preocupações e o que mais contribui para concentrações de dióxido de azoto (NO2) na atmosfera, embora as condições químicas de fundo regional devam também ser consideradas. Neste contexto, a utilização de ferramentas de modelação é crucial para compreender a dinâmica atmosférica e humana a diferentes escalas, e apoiar na definição das melhores estratégias para melhoria da qualidade do ar (EMQA). Esta tese tem como objetivo principal o desenvolvimento e aplicação de um sistema de modelação multiescala que permita simular qualidade do ar e impactos na saúde em cidades. Para isso, foi desenvolvido e operacionalizado o sistema modair4health - multiscale air quality and health risk modelling. Este sistema inclui o modelo online WRF-Chem, que fornece campos meteorológicos e de qualidade do ar da escala regional à urbana, e o modelo CFD VADIS, que utiliza os resultados do WRF-Chem para calcular o impacto das emissões do tráfego rodoviário no escoamento e dispersão de poluentes em áreas urbanas. Para avaliar os impactos na saúde humana, foi também integrado um módulo baseado nas abordagens linear e não-linear da Organização Mundial de Saúde (OMS), e os custos são calculados com base em estudos económicos. A aplicação e avaliação do sistema modair4health permitiram identificar as configurações e dados de entrada mais apropriados, que foram posteriormente utilizados para testar EMQA sobre o caso de estudo, que corresponde a uma das áreas de maior tráfego rodoviário da cidade de Coimbra (Avenida Fernão de Magalhães). O WRF-Chem foi configurado com 3 domínios aninhados (resoluções de 25, 5 e 1 km2), simulados para o ano 2015; enquanto que para o VADIS, foi definido um quarto domínio (resolução de 4 m2) sobre o caso de estudo para simular concentrações de NO2 em dois períodos específicos: uma semana no inverno e outra no verão. Para quantificar os impactos na saúde, as duas abordagens da OMS foram aplicadas ao caso de estudo para avaliar efeitos a curto-prazo. A abordagem não-linear apresentou resultados de saúde mais baixos que aparentemente estão melhor ajustados à realidade local. Por fim, foram avaliadas as potencialidades do sistema no apoio à tomada de decisão, testando dois cenários de gestão do tráfego rodoviário: substituição de 50% da frota de veículos abaixo de EURO 4 por veículos elétricos (ELEC), e introdução de uma Zona de Emissões Reduzidas (LEZ). O cenário ELEC potencia melhorias mais significativas na qualidade do ar e saúde. Este estudo representa um avanço científico na modelação multiescala da qualidade do ar e saúde. O sistema modair4health pode ser facilmente adaptado e aplicado a outros casos de estudo para avaliar a qualidade do ar urbana e impactos na saúde, bem como para testar medidas de controlo da poluição atmosférica.Programa Doutoral em Ciências e Engenharia do Ambient