Air Quality Research Using Remote Sensing

Air pollution is a worldwide environmental hazard that poses serious consequences not only for human health and the climate but also for agriculture, ecosystems, and cultural heritage, among other factors. According to the WHO, there are 8 million premature deaths every year as a result of exposure to ambient air pollution. In addition, more than 90% of the world’s population live in areas where the air quality is poor, exceeding the recommended limits. On the other hand, air pollution and the climate co-influence one another through complex physicochemical interactions in the atmosphere that alter the Earth’s energy balance and have implications for climate change and the air quality. It is important to measure specific atmospheric parameters and pollutant compound concentrations, monitor their variations, and analyze different scenarios with the aim of assessing the air pollution levels and developing early warning and forecast systems as a means of improving the air quality and safeguarding public health. Such measures can also form part of efforts to achieve a reduction in the number of air pollution casualties and mitigate climate change phenomena. This book contains contributions focusing on remote sensing techniques for evaluating air quality, including the use of in situ data, modeling approaches, and the synthesis of different instrumentations and techniques. The papers published in this book highlight the importance and relevance of air quality studies and the potential of remote sensing, particularly that conducted from Earth observation platforms, to shed light on this topic

Atmospheric modeling of natural hazards

Thesis (Ph.D.) University of Alaska Fairbanks, 2021Airborne hazards either in gaseous form or particulate matter can originate from a variety of sources. The most common natural airborne hazards are ash and SO₂ released during volcanic eruptions, smoke emitted caused by wildfires and dust storms. Once released into the atmosphere they can have a significant impact on different parts of the environment e.g. air quality, soil and water, as well as air traffic and ground transportation networks. This latter field is an important aspect of everyday life that is affected during hazardous events. Aviation is one of the most critical ways of transport in this century. Even short interruptions in flight schedules can lead to major economic damages. Volcanic eruptions comprise one of the most important airborne hazards to aviation. These are considered rare as compared to severe weather, but with an extremely high impact. This dissertation focusses on dispersion modeling tools and how they can support emergency response during different phases of volcanic eruption events. The impact of the volcanic ash cloud on the prediction of meteorological parameters and furthermore the dispersion of the ash is demonstrated by applying the Weather Research Forecasting (WRF) model with on-line integrated chemical transport (WRF-Chem) to simulate the 2010 Eyjafjallajökull eruption in Iceland. Comprehensive observational data sets have been collected to evaluate the model and to show the added value of integrating direct-feedback processes into the simulations. The case of the Eyjafjallajökull eruption showed the necessity to further develop the volcanic emission preprocessor of WRF-Chem which has been extended for flexible and complex ash and SO₂ source terms. Furthermore, the thesis describes how scientists could support operational centers to mitigate hazards during a large volcanic eruption event. The author of the dissertation coordinated a large exercise including experts across all Europe within a project funded by the European Union. The exercise aimed to develop and test new tools, models, and data to support real-time decision making in aviation flight planning during a volcanic crisis event. New state-of-the-art modeling applications were integrated into a flight planning software during a fictitious eruption of the Etna volcano in Italy with contributions from scientists, the military and the aviation community.Cooperative Institute for Alaska Research, National Oceanic and Atmospheric Administration cooperative agreement NA13OAR4320056 with the University of AlaskaChapter 1: Introduction --1.1 Airborne hazards and their impact on the environment and aviation -- 1.2 The volcanic risk mitigation system for aviation -- 1.3 Dispersion models support emergency response -- 1.4 Composition of the dissertation -- References. Chapter 2: The effects of simulating volcanic aerosol radiative feedbacks with WRF-Chem during the Eyjafjallajökull eruption, April and May 2010 -- Abstract -- 2.1 Introduction -- 2.2. Simulations setup -- 2.2.1. Model setup and case specifications -- 2.2.2. Volcanic emission preprocessor -- 2.3. Spatial and temporal evaluation of the location of the volcanic plume -- 2.4. Evaluation of meteorological parameters close to the surface -- 2.4.1. Meteorological observations -- 2.4.2. Average meteorological parameters at ground level -- 2.5. Aerosol radiative feedback effects in the model simulations -- 2.5.1. Radiative feedback effects close to the surface -- 2.5.2. Vertical profiles of wind speed and temperature -- 2.5.3. Influence of the radiative feedback effects on the atmospheric stability -- 2.6. The influence of considering the direct effect on the dispersion of the ash cloud -- 2.7. Summary and conclusions -- 2.8. Acknowledgments -- References. Chapter 3: Extension of the WRF-Chem volcanic emission preprocessor to integrate complex source terms and evaluation for different emission scenarios of the Grimsvötn 2011 eruption -- Abstract -- 3.1 Introduction -- 3.2 Extension of the volcanic preprocessor of the WRF-Chem model -- 3.3 WRF-Chem model simulations -- 3.3.1 Model setup -- 3.3.2 Volcanic emission scenarios -- 3.3.3 Model inter-comparison of predicted ash considering aviation regulation aspects -- 3.4 Evaluation of WRF-Chem simulations with observations -- 3.4.1. Comparison of volcanic ash and SO₂ with satellite data -- 3.4.2 Comparison with ground-based observations -- 3.4.2.1 Lidar profiles at selected stations -- 3.4.2.2 Comparison with PM10 observations at selected ground stations -- 3.5. Conclusions -- 3.6 Acknowledgements -- Glossary -- Appendix -- References. Chapter 4: A volcanic-hazard demonstration exercise to assess and mitigate the impacts of volcanic ash clouds on civil and military aviation -- Abstract -- 4.1 Introduction -- 4.2 International exercises -- 4.3 Overview of the EUNADICS-AV demonstration exercise set-up -- 4.3.1 General approach -- 4.3.1.1 The volcanic-eruption scenario -- 4.3.1.2 Data sharing and visualization -- 4.4 Data sets used for the demonstration exercise -- 4.4.1 Artificial observations -- 4.4.1.1 Simulations of the artificial plume evolution -- 4.4.1.2 Generation of artificial observations from SILAM simulations -- 4.4.2 The early-warning system (EWS) -- 4.4.2.1 Volcano observatory, Sicily -- 4.4.2.2 Synthetic ACTRIS EARLINET data -- 4.4.2.3 Synthetic satellite data simulated for IASI and MODIS -- 4.4.3 Model ensemble -- 4.5 The impact of the ash cloud on aviation for the Etna eruption scenario -- 4.5.1 Air navigation service provider -- 4.5.2 Austrian Armed Forces (AAF) -- 4.5.3 Rerouting of flights -- 4.6 Conclusion -- 4.7 Acknowledgements -- Glossary -- References. Chapter 5: Dissertation Summary and Conclusions -- 5.1 Extension and evaluation of the WRF-Chem model -- 5.2 Future perspectives -- References

Atmospheric Composition Observations

The composition of the atmosphere is a critical factor in understanding the nature and magnitude of processes associated with the planet’s energy balance, clouds and precipitation, biogeochemical cycling of nutrients, and public health and welfare. A detailed understanding of trace gases, aerosol particles, and hydrometeors is challenging due to the combination of their physicochemical complexity, variable lifetimes, and spatial inhomogeneity. Recent advances in instrumentation have resulted in improved measurements and an increased understanding of atmospheric composition. Laboratory and field in-situ measurement studies have benefited from such improvements, including improved spatial and temporal resolution, the ability to sample in challenging conditions (e.g., on airborne platforms, in clouds, at widely ranging pressure and temperature conditions), and the ability to measure a wider range of chemical species, and, in the case of aerosol particles, to detect smaller sizes. Remote sensing capabilities have increased in recent years, thus offering new views of atmospheric composition across broad spatiotemporal ranges. Manuscripts related to all aspects of atmospheric observations are included in this Special Issue, including advances in observational techniques and scientific insights into atmospheric composition

Characterising downwind particulate and sulfur dioxide air pollution from volcanic emissions

One of the hazards of volcanic eruptions is the emission of gas and aerosol into the atmosphere, which can cause damage to the environment and human health as well as impacting climate. Emissions from effusive volcanic eruptions and passively degassing volcanoes typically remain in the troposphere where they are advected by the wind and can cause deterioration to air quality across a downwind region. Of the emitted gases, sulfur dioxide (SO2) is often highly concentrated with respect to the background atmosphere and has important air quality and environmental consequences. Over time after emission from the volcanic source, SO2 may be converted to sulfate aerosols through atmospheric processes, leading to additional air quality concerns with an increase in fine particulate matter (PM). This thesis aims to characterise the SO2 and PM air quality in regions downwind of tropospheric volcanic emissions. Three study sites are examined; Kılauea volcano on the Island of Hawai‘i, Masaya volcano in Nicaragua and Fagradalsfjall volcano in Iceland. The SO2 and PM concentrations in the downwind regions are monitored using highly accurate reference-grade air quality instruments, and a variety of lower-cost miniaturised sensors. Low-cost sensors are increasingly used for air quality measurements, and in this thesis I investigate their effectiveness for monitoring in volcanic environments. Low-cost sensors are used at Masaya volcano as a first-attempt to establish an air quality monitoring network. At Kılauea volcano, a long time-series of SO2 and PM data is examined to determine air quality deterioration during a period of extremely heightened volcanic activity. At Fagradalsfjall volcano, the impact of a small eruption in proximity to densely-populated areas is examined and the population exposure to volcanic SO2 is estimated using a plume dispersion model. These studies increase the knowledge of SO2 and aerosol dispersal from volcanic sources, especially for those communities in the affected areas

Proceedings of Abstracts 10th International Conference on Air Quality Science and Application

This 10th International Conference in Air Quality - Science and Application is being held in the elegant and vibrant city of Milan, Italy. Our local hosts are ARIANET and ARPA Lombardia both of whom play a leading role in assessing and managing air pollution in the area. The meeting builds upon the series that began at the University of Hertfordshire, UK in July 1996. Subsequent meetings have been held at the Technical University of Madrid, Spain (1999), Loutraki, Greece (2001), Charles University, Prague, Czech Republic (2003), Valencia, Spain (2005), Cyprus (2007), Istanbul, Turkey (2009) Athens, Greece (2012) and Garmisch-Partenkirchen, Germany (2014). Over the last two decades controls to limit air pollution have increased but the problem of poor air quality persists in all cities of the world. Consequently, the issue of the quality of air that we breathe remains at the forefront of societal concerns and continues to demand the attention of scientists and policy makers to reduce health impacts and to achieve sustainable development. Although urbanisation is growing in terms of population, transport, energy consumption and utilities, science has shown that impact from air pollution in cities is not restricted to local scales but depends on contributions from regional and global scales including interactions with climate change. Despite improvements in technology, users still demand robust management and assessment tools to formulate effective control policies and strategies for reducing the health impact of air pollution. The topics of papers presented at the conference reflect the diversity of scales, processes and interactions affecting air pollution and its impact on health and the environment. As usual, the conference is stimulating cross-fertilisation of ideas and cooperation between the different air pollution science and user communities. In particular, there is greater involvement of city, regional and global air pollution, climate change, users and health communities at the meeting. This international conference brings together scientists, users and policy makers from across the globe to discuss the latest scientific advances in our understanding of air pollution and its impacts on our health and environment. In addition to the scientific advances, the conference will also seek to highlight applications and developments in management strategies and assessment tools for policy and decision makers. This volume presents a collection of abstracts of papers presented at the Conference. The main themes covered in the Conference include: Air quality and impact on regional to global scales Development/application/evaluation of air quality and related models Environmental and health impact resulting from air pollution Measurement of air pollutants and process studies Source apportionment and emission models/inventories Urban meteorology Special session: Air quality impacts of the increasing use of biomass fuels Special session: Air quality management for policy support and decisions Special session: Air pollution meteorology from local to global scales Special session: Climate change and human health Special Session: Modelling and measuring non-exhaust emissions from traffic Special session: Transport related air pollution - PM and its impact on cities and across EuropeFinal Published versio

Relación de las variables meteorológicas en la dispersión espacio temporal de los contaminantes atmosféricos (PM2.5, PM10, SO2, NO2, O3) del distrito de Pacocha, Moquegua, 2019 – 2020.

Los efectos sinérgicos de varios contaminantes del aire asociados con las variables meteorológicas aún no se han estudiado ampliamente ni se han comprendido completamente, especialmente en la costa sur del Perú. El objetivo principal de la presente tesis fue determinar la relación de las variables meteorológicas (temperatura, humedad relativa, velocidad del viento y la dirección del viento) en la dispersión espacio temporal de los contaminantes atmosféricos (NO2, O3, SO2, PM10 y PM2.5) en el distrito de Pacocha, provincia de Ilo, para los años 2019 y 2020. Los datos de las variables meteorológicas y los valores de contaminantes atmosféricos, fueron obtenidos de la estación de monitoreo de calidad del aire de la UNAM – Moquegua

Évaluation et application de MERRAero, une réanalyse des aérosols atmosphériques développée par la NASA

La Modern-Era Retrospective Analysis for Research and Application (MERRA) est une réanalyse développée par le Global Modeling and Assimilation Office (GMAO) à la National Aeronautics and Space Administration (NASA) aux États-Unis qui intègre des données observées et des données modélisées pour reproduire une base de données complète dans le temps et l'espace de plusieurs variables atmosphériques (température, vitesse et direction du vent, humidité, pressions, etc.) depuis 1979. Afin de reproduire une analyse intégrée du système terrestre, le GMAO effectue d'autres réanalyses en parallèle : une réanalyse des océans (MERRAOcean), une réanalyse de la surface solide de la Terre (MERRALand) et une réanalyse de la composition de l'atmosphère (MERRAero), cette dernière constituant le sujet central de cette thèse. La 1ère version de MERRAero intègre des données de la profondeur optique des aérosols (AOD) mesurée par MODIS-Terra et MODIS-Aqua, en orbite autour de la Terre depuis 2000 et 2002 respectivement, et les données d'un modèle de chimie atmosphérique qui simule la concentration de cinq espèces dominantes d'aérosols, soit les particules de sulfate, de carbone organique, de carbone noir, de poussière et de sel de mer. La réanalyse reproduit donc la concentration de ces cinq espèces d'aérosols partout sur la Terre, avec une résolution de 0,5º de latitude, 0,625º de longitude et 72 niveaux en altitude, à une fréquence horaire, en plus de leur contribution individuelle à l'AOD totale. Une reconstruction peut ensuite être appliquée pour obtenir la concentration totale des matières particulaires, un contaminant couramment pris en compte pour évaluer la qualité de l'air. MERRAero constitue une avancée importante dans l'étude de la composition atmosphérique à l'échelle globale. Elle met à la disposition de la communauté scientifique un outil novateur qui lui permet d'étudier une vaste gamme de problèmes liées à la pollution atmosphérique qu'aucun réseau de surveillance ne peut accomplir, particulièrement dans les régions dépourvues de toute surveillance fiable. MERRAero doit cependant traverser un processus d'évaluation rigoureux avant d'être jugée apte à accomplir ses fonctions. Certaines de ses capacités ont déjà été évaluées à certains endroits, notamment sa simulation de l'AOD au-dessus de certaines régions du monde et sa simulation de la concentration des oxydes de soufre aux États-Unis. L'objectif de cette thèse est de poursuivre les travaux d'évaluation avec une emphase sur la concentration des différentes espèces d'aérosols simulées à la surface par MERRAero dans plusieurs régions du monde. Une fois que l'évaluation ait été jugée favorable, MERRAero a ensuite été appliquée à une étude sur la pollution urbaine de l'air à l'échelle globale. La concentration de plusieurs espèces d'aérosols simulée par MERRAero à la surface depuis 2003 a été comparée à des données d'observations provenant de différents réseaux de surveillance autour du monde : le Interagency Monitoring of Protected Visual Environments (IMPROVE) aux États-Unis, le European Monitoring and Evaluation Programme (EMEP) en Europe, celui du Ministère de la protection environnementale en Israël et celui de l'Administration de la protection environnementale à Taïwan. Plusieurs indicateurs statistiques ont été calculés, et des analyses spatiales et temporelles ont été effectuées pour évaluer l'exactitude de MERRAero, identifier ses lacunes importantes et formuler des recommandations pour améliorer ses versions subséquentes. L'évaluation aux É.-U. et en Europe en milieu rural a démontré que MERRAero reproduit bien la concentration des particules de sulfate et de carbone d'origine anthropique. La concentration des particules de carbone d'origine naturelle, provenant notamment des feux de forêt, a cependant été largement surestimée, causant ainsi un biais important en été. MERRAero a surestimé aussi la concentration des particules de sable de sources lointaines, telles que le Sahara et les déserts en l'Asie de l'Est qui affectent légèrement la composition des aérosols aux É.-U. L'évaluation a reproduit des résultats favorables en milieu urbain malgré la résolution de MERRAero qui ne capture pas toutes les sources d'aérosols, causant ainsi des fluctuations saisonnières non conformes aux observations. L'évaluation a reproduit des résultats très favorables en Israël. Sa proximité au Sahara et aux déserts du Moyen-Orient suggère que MERRAero simule très bien la concentration des particules de sable d'origine locale. À Taïwan, MERRAero a reproduit la concentration des aérosols généralement bien à l'exception des mois d'hiver, lorsque Taïwan est le plus affecté par l'advection de pollution d'origine chinoise.Malgré les lacunes identifiées, dans l'ensemble, l'évaluation a reproduit des résultats jugés suffisamment favorables pour que MERRAero soit appliquée dans une multitude de problématiques, notamment à l'étude de la pollution urbaine de l'air à l'échelle globale. Cette analyse a démontré l'impact que les politiques environnementales et la récession économique des dernières années ont eu sur la pollution atmosphérique des villes d'Amérique du Nord, d'Europe et d'Asie de l'Est. Même l'air des villes chinoises, lesquelles sont aux prises avec de sérieux problèmes de pollution depuis plusieurs années, s'est amélioré grâce à une initiative du gouvernement à réduire les émissions de contaminants atmosphériques. Les villes de l'Inde et du Bangladesh sont les seules à avoir vu leur situation se détériorer, due à une forte urbanisation et industrialisation. La qualité de l'air des villes d'Amérique du Sud et d'Afrique subsaharienne s'est aussi améliorée par un ralentissement des activités de déforestation au cours des dix dernières années, particulièrement dans la forêt amazonienne

Wildland Fire Smoke in the United States

This open access book synthesizes current information on wildland fire smoke in the United States, providing a scientific foundation for addressing the production of smoke from wildland fires. This will be increasingly critical as smoke exposure and degraded air quality are expected to increase in extent and severity in a warmer climate. Accurate smoke information is a foundation for helping individuals and communities to effectively mitigate potential smoke impacts from wildfires and prescribed fires. The book documents our current understanding of smoke science for (1) primary physical, chemical, and biological issues related to wildfire and prescribed fire, (2) key social issues, including human health and economic impacts, and (3) current and anticipated management and regulatory issues. Each chapter provides a summary of priorities for future research that provide a roadmap for developing scientific information that can improve smoke and fire management over the next decade