Supporting Climate Adaptation Measures in Small- to Medium-Sized Austrian Cities Using Climate Modelling

This study outlines the results of current climate conditions for the city of Mödling, Klagenfurt and Salzburg located in Austria. Furthermore, it will analyse specific measures regarding climate adaptation, which are potentially realizable. To characterize the current climate conditions with the average number of summer days per year (SD y−1), we use the microscale urban climate model MUKLIMO_3, in combination with a trilinear interpolation method. For the reference model simulation, we use atmospheric observations from 1981 to 2010 provided by one weather station located in a rural site near each city. We combined different land use data sets with various spatial resolutions to evaluate precise properties for the land use classification. Furthermore, we compared changes in SD y−1 to the reference simulation to evaluate the effectiveness of the here proposed adaptation strategies. Specifically, we consider two types of adaptation measures: (i) an increase in the shortwave reflectivity of impervious and sealed areas and (ii) an increased number of low-vegetated areas (i.e. lawns on streets and at roof level) and high-vegetated areas (i.e. bushes and trees). The results of the individual simulations indicate a substantially decreased SD y−1 by up to − 7.3 (− 10.9%) for the case of highly reflective roofs and up to − 7.7 (− 22.7%) for the case of an increased number of trees. A combination of both pathways leads to a decrease in SD y−1 by up to − 19.4 (− 29.3%), indicating a clear potential to mitigate the heat burden in each city