Adapting cities to climate change: a systemic modelling approach

To answer the climate change challenge, all states have to reduce their greenhouse gas emissions, but also to adopt adaptation measures to limit the negative impacts of global warming on the population, the economy and the environment. The question arises especially for cities. Because of complex interactions between climate change, the evolution of cities and its inhabitants, studying adaptation strategies for cities requires a strong interdisciplinary approach: urban planners, architects, meteorologists, building engineers, economists, social sciences. Our four-step methodology consists firstly of defining interdisciplinary scenarios; secondly of simulating long term city evolution based on socio-economic and land-use models; thirdly of calculating impacts with physical models (such as TEB), and finally of calculating the indicators quantifying the adaptation strategies. Both city evolution and climate change influence the energy consumption evolution. This depends on which impact we focus on. Another finding is that the UHI is important to accurately reproduce the energy consumption in cities. The UHI should then be taken into account in operational estimation of building energy demands. Finally, the major finding of this work is that it is possible to perform interdisciplinary systemic modelling in order to evaluate several adaptation strategies for a very broad range of topics.