Numerical modelling of the urban climate as an integrated part of environmental assessments

The starting point of our study is the Environmental Impact Assessment (EIA) Directive 2014/52/EU, which has strengthened the consideration of climate change and “catastrophic events” in environmental assessments, which includes adaptation-relevant local impacts of climate change on projects due to climate change and also the project's impacts on the global as well as local (urban) climate. This article shows to what extent small-scale simulations of the urban climate can be applied and used within the framework of the environmental assessment of a project. We investigate so called “reasonable planning alternatives” in terms of urban design variants and compare them with their bioclimatic effects (human health as a protection good). The investigated area is located in the City of Bottrop (Germany). The procedure was coordinated with those responsible in the city's administration within the framework of a Living Lab, so that the results can be incorporated into the planning decision-making process which underlines its scientific validity and applicability. By its unique methodological approach, this article brings numerical urban climate modelling together with the legal requirements of European Framework Directives and shows that urban climate studies of reasonable planning alternatives can meet the current legal requirements for environmental assessments. [Display omitted] •Climate change and extreme events have various impacts on human health.•Small-scale simulations of the urban climate can help to identify climate impacts.•Investigation of climatic effects of different development variants of a planning.•The models are regarded as analysis tools within an environmental assessment.