ADAPT-UHI

Urban Climate Change Adaptation for Austrian Cities: Urban Heat Islands.

Increased temperatures in urban areas due to high amounts of impervious surfaces, a lack of vegetation and concentrated urban structures is called the Urban Heat Island (UHI) effect, which in combination with heat waves, can negatively impact human health and well-being. To address the UHI effect and extreme heat in cities, urban planners need support in developing strategies for climate change adaptation. Urban planners in small- to medium-sized cities in Austria need support, which was the overall aim of the ADAPT-UHI project.

Three pilot cities participated in the project: Mödling, Klagenfurt am Wörthersee (hereafter Klagenfurt) and Salzburg. Initial workshops were held with each city to understand their needs in terms of climate change adaptation and to obtain city-specific data for input to an urban climate model. This was used to run various scenarios to determine the effects of implementing different adaptation measures including white measures (i.e., those that increase the reflectivity of roofs, walls and road surfaces – collectively referred to as the White City), green measures (i.e., those that increase the cooling of the ambient air temperature by adding vegetation such as green roofs, increasing the number of trees and greenspace, etc. – collectively referred to as the Green City) and the combination of both sets of measures (Combined scenario). A cost-benefit analysis of these scenarios was then undertaken, considering heat-reduction related benefits as well as ecosystem service benefits. Subsequent workshops were held with each city to present the results, tailor the adaptation scenarios and to present recommendations based on the modelling results and best practices.

The project also developed other tools to guide urban planning for climate change adaptation. The first was a UHI Risk Index for Austria, produced at a 100 m resolution, which is based on a combination of meteorological indicators, land cover, settlement data and demographic indicators, including the population most at risk. The second was the development of Urban Climate Quality Maps for each pilot city, which provide information on the areas of the city that have the largest evaporative cooling from vegetation and water and where there is shading from buildings and vegetation, which also contributes to cooling. Both tools can be used by urban planners to guide the implementation of planning interventions in the future.