Heat stress in urban area: data fusion of observations, modeling and geospatial information

Cities have a direct impact on the local climate. The heating of surfaces and materials in urban area and the production of heat by traffic and human activity contribute to the Urban Heat Island (UHI) effect. This local climate will be even more dangerous with climate change. Climate projections for the world suggest elevated minimum and maximum temperatures and more frequent day with higher temperatures (heat wave). Hence, climate change is threatening human well being and health. Today, more than 50% of the world population lives in urban areas and humans spend more than 80% of their time in confined spaces. This can be affected negatively by indoors temperatures. Indoor temperatures are of special importance for well-being and health in general.Quantitative information about outdoor thermal comfort, on various temporal and spatial scales, is required to design better cities and mitigate heat problems not only for warm as well as temperate climates. The overall objective of this study is to explore the relation between indoor and outdoor temperature by urban features such as geometry (type of urban structure), housing areas, building arrangements and several other factors. We use the SURFEX model (that is implemented in several weather prediction models and can also be used alone) to estimate urban temperatures (in street canyons and inside buildings). Therefore, two questions arise: how to represent the outputs of the SURFEX model both spatially and temporally? This work is part of a study conducted in summer 2015 which gathered data from air temperature sensors in five apartments. So for our study, the information given by the model is completed by measures to study the influence of building characteristics and situation on temperatures. Furthermore, it highlights the importance of thermal comfort in climate scenarios to describe the combined effects of changes in multiple apartments and to more realistically measure its impact on humans