Changes in urban design and traffic policy, demography, climate and associated adaptation and mitigation measures, and environmental policies, are likely to modify both outdoor and indoor air quality and therefore public health. The proposed project aims to improve our understanding of future exposure situations and their impact on health, from an interdisciplinary approach. This will be achieved by using various state-of-the-art atmospheric models and measurements and epidemiological studies and reviews. To assess population full exposure we will develop an integrated view accounting both for indoor and outdoor air pollution as well as for population time-activity data. Coupled modelling systems will be developed to assess the interaction between climate and urbanization. We will estimate new dose-response functions between health outcomes and air pollution as well as temperature in order to better estimate the effects on the foetus and young children. Ultimately we will simulate scenarios of future urban climate and air quality, combine future exposure scenarios, population scenarios and exposure-response functions to describe the effects of different trends and relevant policies on relative risk and burden of illness attributed to urban pollutants, especially particles and ozone, and their interactions with extreme temperatures.
This project will in particular address the issue of the mitigation strategies that can be used to reduce urbanization and climate change effects on the local urban meteorology and air quality. The accurate determination of the impact of such scenarios is hindered, at the large-scale end by the change in global climate and at the small-scale end by the difficulty in modelling details of surface and emissions. One of the main objectives of the project is to bridge processes across these scales using a suite of state-of-the-art atmospheric model from global to local (i.e. urban). With applications in several large European cities including Paris, Stockholm and Brussels we will study the impact of several alternative adaptation scenarios on urban air-quality and human health to a mid-century horizon (2030-2060) accounting for the effects of changing urban climate. To account for increased heating over urban areas (heat island effect) and atypical mixing processes induced by the three-dimensional structure of the city and artificial material (e.g. buildings, street canyons, urban vegetation, green roofs etc.) we will run dedicated flux models over the city (Town Energy Budget models). Future emission projections will be developed in collaboration with local agencies of each city based on available scenarios on local policies, urban planning, traffic management, vehicle fleet, economic growth etc. State-of-the-art chemistry transport models (MATCH and CHIMERE) will be used to assess concentrations at urban scale under the aforementioned adaptation scenarios. Novel subgrid scale approaches will be developed to describe air pollutant concentrations within the intra-urban area with special attention to street concentrations. We will also evaluate the impact of the implementation of Low Emission Zones (LEZ) in several European cities in Germany, France and Sweden on traffic-related air pollutants levels.
Due to the overwhelming amount of time spent indoor (homes, workplaces, transport) by the population of the urban centres of the industrial countries personal exposures are driven by indoor air-quality. Not accounting for exposure indoors leads to exposure misclassification and is bound to modify epidemiological results. Therefore, to link air quality modelling activities with epidemiological models it is necessary to account for indoor/outdoor relationships. Several approaches will be followed in this project including indoor air-quality measurements, numerical models for air transfer from outdoors indoors, personal exposure measurements and integrating modelling systems combining air-quality data, indoor/outdoor relationships and human activity patterns. With these activities we study further how indoor/outdoor relationships depend on building characteristics (building envelope, ventilation and energetic systems), meteorological conditions, the proximity to outdoor air-pollution sources (e.g. busy roads) or the type of area (urban, suburban, rural).
Epidemiological studies within this project will focus on vulnerable groups. More specifically, we will study early life exposures before birth and in the first year of life both as chronic exposures and as triggers. Birth cohorts and large birth register cohorts will be used to construct exposure-response functions between pregnancy outcomes (e.g. birth weight and risk of preterm birth) and air pollution (PM from different sources, pollen and ozone) as well as temperature. In addition to measured concentrations we will improve exposure data using output data from the air-quality and exposure modelling activities described above.
In the final phase, scenario-based health impact assessments will combine exposure information from climate models, emission scenarios, policy evaluation studies and concentration calculations with exposure-response functions from epidemiological studies of vulnerable groups within the project and previously published functions for mortality and hospital admissions. We will discuss effects of socioeconomic and demographic trends, describe the predicted health impacts and the benefits associated with different interventions and policies such as LEZ and other urban changes such as residential density, urban vegetation, energy saving buildings etc.
The study will benefit from a large consortium with an interdisciplinary mix of experts involved in many projects (meteorology, air quality modelling, exposure measurements, epidemiology, environmental management, health impact assessment) and with large experience of interaction with policy-makers and stakeholders. There will be many partners in each WP and staff visiting and working in other partner organizations. We plan to produce novel scientific papers, policy-relevant end-user reports and arrange a final seminar for policy makers.