Air Pollution and Emission Reductions over the Po-Valley: Air Quality Modelling and Integrated Assessment

The Po-valley located in northern Italy at the footstep of the Alps is characterized by a high density of anthropogenic emissions (inhab) and by the frequent occurrence of stagnant meteorological conditions. The area has therefore been identified as one hot spot place where pollutant levels will remain problematic in spite of application of the current European legislation devoted to air pollution control. By 2020, health impact on population and effects on ecosystems by ozone and eutrophication are indeed calculated to be amongst the highest in Europe and anthropogenic fine particulate matter levels are expected to be responsible for a loss of ten months of life expectancy. In general, long-range transported air pollution in the Po-Valley represents only a fraction of 30-40%, stressing the importance of local control measures in the area to efficiently reduce the impact of air pollution. In the frame of a collaboration agreement between the JRC (Joint Research Centre of the European Commission) and the government of the Lombardy region, a Model Inter-comparison exercise over the PO-valley (POMI) is organised to explore the changes in urban air-quality predicted by different air quality models in response to changes in emissions in the Po-Valley. POMI focuses on ambient levels of ozone and PM. Current Legislation (CLE) and Maximum Technically Feasible Reduction (MTFR) Emission scenarios are analysed at different spatial scales together with a set of ¿in-between¿ emission reductions corresponding to the application of regional air-quality plans over the Po-Valley and in particular over the Lombardy region. In parallel to this model inter-comparison exercise, an integrated assessment tool is being developed to design and assess the effectiveness of regional abatement policies. This tool is planed to make use of information available at the local/regional scale (technological costs, emission factors¿) and to allow investigating the efficiency of both technical and non-technical abatement measures. POMI is expected to provide information useful for the development of sectoral regional source relationships and for better accounting of the different sources of model-related uncertainties (emissions, meteorology¿) in the assessment of efficient strategies. In this work, an overview of the structure of the regional integrated assessment tool will be provided and its links with the POMI modelling exercise discussed.JRC.DDG.H.4-Transport and air qualit

Methods for Regional Integrated Assessment: High resolution gridded emission distribution in the LUISA Platform

This report illustrates the progresses made towards the inclusion of air quality related issues in the Land Use-based Integrated Sustainability Assessment (LUISA) platform. It focuses on the description of the methodology to derive high-resolution gridded-emission spatially geo-referenced layers from outputs and datasets integrated in LUISA. In the framework of the integration of the Regional Integrated Assessment Tool (RIAT model) and the Land Use Modelling Integrated Sustainability Assessment (LUISA) platform, we implemented the downscaling of atmospheric emission data from national level to very high spatial resolution (100m). The GAINS model (IIASA) provides the input emission data for different scenarios, up to year 2030, which are disaggregated based on 34 different surrogates. Each surrogate is calculated by means of the integration of several proxies derived by statistical datasets, ancillary models and GIS layers in the framework of the LUISA platform. The preliminary results for NOx, PM10 and NH3 (year 2010) are presented in this report together with their first assessment, based on existing emission maps at 7 and 10 Km resolution. Future steps for further refinements are also discussed.JRC.H.8-Sustainability Assessmen

Source apportionment to support air quality management practices: A fitness-for-purpose guide (V 3.1)

Information on the origin of pollution constitutes an essential step of air quality management as it helps identifying measures to control air pollution. In this document, we review the most widely used source-apportionment methods for air quality management. Using simple theoretical examples we highlight the differences among these methods and explain why and under which circunstances they lead to different results and therefore different conclusions in the context of air quality management. These differences are a consequence of the intrinsic assumptions that underpin the different methodologies and determine/limit their range of applicability. We show that ignoring their underlying assumptions is a risk for efficient/successful air quality management as these methods are sometimes used beyond their scope and range of applicability. The simplest approach based on increments, contributions obtained through receptor models or tagging approaches built in air quality models as well impacts obtained via “brute-force” methods are discussed. The guide is organised as follows: the different source apportionment approaches and their associated properties are presented in Part I, simple examples are introduced in Part II to illustrate the main differences in terms of results while Part III focuses on the fitness-for-purpose aspects of the different methods. Finally Part IV lists and briefly discusses a series of open issues.JRC.C.5-Air and Climat

A novel approach to screen and compare emission inventories

A methodology is proposed to support the evaluation and comparison of different types of emission inventories, and more specifically the comparison of bottom-up versus top-down approaches. The strengths and weaknesses of the methodology are presented and discussed based on an example. The approach results in a “diamond” diagram useful to flag out anomalous behaviors in the emission inventories and to get insight on possible explanations. In particular, the “diamond” diagram is shown to provide meaningful information in terms of: discrepancies between the total emissions reported by macro-sector and pollutant, contribution of each macro-sector to the total amount of emissions released by pollutant, and the identification and quantification of the different factors causing the discrepancies between total emissions. Its main strength as an indicator is to allow investigating the relative contribution of activity and weighted emission factors. A practical example in Barcelona is used for testing and to provide relevant information for the analyzed emission datasets. The tests show the capability of the proposed methodology to flag inconsistencies in the existing inventories. The proposed methodology system may be useful for regional and urban inventory developers as an initial evaluation of the consistency of their inventories.JRC.H.2-Air and Climat

Comparing air quality model performance for planning applications

The current policy making needs for emission abatement of air pollutants in Europe call for having simple yet robust tools that allow evaluating the effect of measures and sorting those that produce the most significant effects. As a result, the FAIRMODE Planning Working Group (WG4) seeks to develop a consistent framework for streamlining the understanding of models in order to identify more efficiently the relationship between changes in emissions and their effect in ambient concentration through a series of indicators or potencies. The comparison of sector-specific potencies was carried out using the Delta Tool for the AERIS integrated assessment model for the Iberian Peninsula and the SERCA modelling system, on which it is based. Air quality observations from 11 monitoring stations located in Spain and Portugal were used as independent comparison dataset, focusing on a winter and summer month (January and August), as well as on an annual basis. The comparison revealed that the main difference between AERIS and SERCA is the description of the non-linear relationship between changes in emissions and the formation of secondary pollutants (e.g. secondary particles, ground-level ozone). This is a consequence of the linear simplification that was used to construct AERIS, as opposed to the deterministic formulation that is contained in SERCA and is basically composed of the WRF-CMAQ ensemble. The comparison also suggested differences in the ability to reproduce seasonal variations of pollutants, something which is a consequence of the annual character of AERIS. However, AERIS is able to reproduce its parent air quality model (SERCA) and complies with the general modelling performance requirements stipulated under FAIRMODE. Moreover, its simplified approach, as evidenced by the values of the potencies allows identifying the interactions between emissions and concentrations, facilitating choosing mitigation measures depending on the abatement needs. Additionally, the ability of AERIS to reproduce ambient concentrations under a simplified approach makes it a robust alternative to SERCA for informing policy making and planning in Spain

Emissions of Carbonaceous Particulate Matter and Ultrafine Particles from Vehicles-A Scientific Review in a Cross-Cutting Context of Air Pollution and Climate Change

Featured Application Key conclusions and recommendations are proposed to enlighten decision makers in view of the next regulations on vehicle emissions in Europe and worldwide through the synergistic contexts of air quality and climate change. Airborne particulate matter (PM) is a pollutant of concern not only because of its adverse effects on human health but also on visibility and the radiative budget of the atmosphere. PM can be considered as a sum of solid/liquid species covering a wide range of particle sizes with diverse chemical composition. Organic aerosols may be emitted (primary organic aerosols, POA), or formed in the atmosphere following reaction of volatile organic compounds (secondary organic aerosols, SOA), but some of these compounds may partition between the gas and aerosol phases depending upon ambient conditions. This review focuses on carbonaceous PM and gaseous precursors emitted by road traffic, including ultrafine particles (UFP) and polycyclic aromatic hydrocarbons (PAHs) that are clearly linked to the evolution and formation of carbonaceous species. Clearly, the solid fraction of PM has been reduced during the last two decades, with the implementation of after-treatment systems abating approximately 99% of primary solid particle mass concentrations. However, the role of brown carbon and its radiative effect on climate and the generation of ultrafine particles by nucleation of organic vapour during the dilution of the exhaust remain unclear phenomena and will need further investigation. The increasing role of gasoline vehicles on carbonaceous particle emissions and formation is also highlighted, particularly through the chemical and thermodynamic evolution of organic gases and their propensity to produce particles. The remaining carbon-containing particles from brakes, tyres and road wear will still be a problem even in a future of full electrification of the vehicle fleet. Some key conclusions and recommendations are also proposed to support the decision makers in view of the next regulations on vehicle emissions worldwide

A multi-pollutant and multi-sectorial approach to screening the consistency of emission inventories

Some studies show that significant uncertainties affect emission inventories, which may impeach conclusions based on air-quality model results. These uncertainties result from the need to compile a wide variety of information to estimate an emission inventory. In this work, we propose and discuss a screening method to compare two emission inventories, with the overall goal of improving the quality of emission inventories by feeding back the results of the screening to inventory compilers who can check the inconsistencies found and, where applicable, resolve errors. The method targets three different aspects: (1) the total emissions assigned to a series of large geographical areas, countries in our application; (2) the way these country total emissions are shared in terms of sector of activity; and (3) the way inventories spatially distribute emissions from countries to smaller areas, cities in our application. The first step of the screening approach consists of sorting the data and keeping only emission contributions that are relevant enough. In a second step, the method identifies, among those significant differences, the most important ones that provide evidence of methodological divergence and/or errors that can be found and resolved in at least one of the inventories. The approach has been used to compare two versions of the CAMS-REG European-scale inventory over 150 cities in Europe for selected activity sectors. Among the 4500 screened pollutant sectors, about 450 were kept as relevant, among which 46 showed inconsistencies. The analysis indicated that these inconsistencies arose almost equally from large-scale reporting and spatial distribution differences. They mostly affect SO2 and PM coarse emissions from the industrial and residential sectors. The screening approach is general and can be used for other types of applications related to emission inventories.Peer ReviewedPostprint (published version

Effect of Sea Breeze on Air Pollution in the Greater Athens Area. Part II: Analysis of Different Emission Scenarios

The Mediterranean Campaign of Photochemical Tracers–Transport and Chemical Evolution that took place in the greater Athens area from 20 August to 20 September 1994 has confirmed the role of sea-breeze circulation in photochemical smog episodes that had been suggested already by a number of experiments and numerical studies. The meteorological and photochemical modeling of this campaign were discussed in Part I. Part II focuses on the study of the 14 September photochemical smog event associated with a sea-breeze circulation. The objective of the study is to identify and to understand better the nonlinear processes that produce high ozone concentrations. In particular, the effect of land and sea breezes is investigated by isolating the effect of nighttime and daytime emissions on ozone concentrations. The same principle then is used to isolate the effect on ozone concentrations of the two main sources of emissions in the greater Athens area: the industrial area around Elefsis and the Athens urban area. Last, the buildup of ozone from one day to another is investigated. From this study, it comes out that ozone production in the Athens area is mainly a 1-day phenomenon. The increased values of photochemical pollutant (up to 130 ppb at ground level) reached during summertime late afternoons on mountain slopes to the north and northeast of the city are related mainly to the current-day emissions. Nevertheless, the recirculation of old pollutants can have an important effect on ozone concentrations in downtown Athens, the southern part of the peninsula, and over the sea, especially near Aigina Island

Support to the review of the Thematic Strategy on Air Pollution: JRC’s contribution to the 2nd Stakeholder meeting January 2012

Although efforts of the EU to reduce air pollution have led to important reductions of emissions within the Member States, millions of people are still exposed to air pollutants at concentration levels that may endanger their health and air pollution is still causing relevant damage to crops and ecosystems. On this background, the European Commission has decided to review its Thematic Strategy for Air Pollution (TSAP) by 2013 at latest, and do this through a consultation process, led by DG ENV, with a broad group of stakeholders. The present report contains the presentations made by JRC staff at the second Stakeholder Meeting, held in January 2012JRC.H.2-Air and Climat