Scenarios of the cantonal climate model

The climate model is based on a windy weather in summer as a meteorological framework, as the climatic effects of settlements develop especially during windy weather conditions with low cloud cover in summer. Characteristic of this (high-pressure) weather is the local formation of cold air flows (river winds in flat position and cold air drains above the slopes), which are driven by the temperature gradient between cool open spaces and warmer residential areas and contribute to a reduction of the heat load in the development. This is less about staying outdoors but rather about reducing heat in the interior to improve the sleeping environment conditions. For this purpose, the meteorological parameters of ground-level air temperature, cold air production rate, the ground-level cold air flow field and the cold air volume flow rate were modelled for the night situation. The thermal load during the day outdoors is represented by the Physiologically Equivalent Temperature (PET). For the future scenario in 2060, an average summer temperature increase of 2.6 K is used (see Chapter 3.4.4 Explanatory Report). The different usage structures have an intensifying effect (surfaced spaces) or weakening (green spaces). In general, however, both the green areas and the settlement area are getting warmer. However, the green spaces will also provide cold air in the future. However, this – under the influence of climate change – is slightly warmer compared to the present, but still cooler than the settlement areas. The relative temperature differences between land use and air exchange as a whole remain similarly pronounced. [Explanatory report](https://geofiles.be.ch/geoportal/pub/lpi/KLIMAMODELL_BE_Bericht_DE.pdf). The simulated parameters form the basis for the derivation of the climate analysis and planning guidance maps.