Urban challenge - green infrastructure and heat stress
As part of the project "Green City of the Future - Climate Resilient Neighbourhoods in a Growing City" (funded by the BMBF), we conducted extensive neighbourhood studies together with the Ludwig Maximilian University of Munich (LMU) and the Chair for Strategy and Management of Landscape Development at the Technical University of Munich (TUM).
The focus was on building and social density as well as inner-city greening as driving and mitigating factors for heat stress. By analysing satellite images and urban and European geoinformation data, the land use as well as the extent and quality of greening in two urban areas of Munich were investigated. The population density in these neighbourhoods was also determined.
Urban Green Infrastructure (UGI) and Urbanisation
Urban green infrastructure plays a crucial role for cities that want to meet the challenges of urbanisation and climate change. It has the potential to mitigate the negative impacts of urban density and the heat island effect, and to improve the environmental and social resilience of cities and their inhabitants.
The study identifies contextual, psychological and social factors that influence people's subjective evaluation of urban green infrastructure, density and heat stress. Planning recommendations for effective, context-specific and user-centred design are developed to enhance the social and health benefits of UGI in limited spaces. A mixed methods approach combining social surveys (LMU), GIS analysis (bifa) and microclimate modelling (TUM) was used.
Field studies in two contrasting districts of Munich
A densely built-up and barely vegetated inner-city neighbourhood and a neighbourhood on the outskirts of the city described as "green and compact" were considered. Both locations could be assessed on the basis of geostatistical data and mean radiant temperature modelling with regard to their supply of green infrastructure, building and population density, and summertime outdoor heat load. This assessment is compared with the subjective assessment of the residents from personal questionnaires and semi-standardised interviews.
The results indicate that the existence and the level of urban green inf-rastructure are not decisive for the perception of urban heat and density as well as for neighbourhood attractiveness. Rather, it is the perceived accessibility of green spaces and their design, quality and contextual factors such as traffic or the presence of other people that define their value for urban dwellers.