Regional Mountain Conference

The Tyrolean Inn Valley is a climatically sensitive area due to its function as an alpine trough valley with a high settlement density. Approximately half of Tyrol’s population lives along this central valley axis between the Northern Limestone Alps and the Central Alps. Over recent decades, a clear warming trend has been observed, expressed by an increasing number of hot days and heat waves. In general, the Alpine region is particularly affected by climate change. Against this background, climatic stress conditions and compensatory processes in the Inn Valley between Landeck and Kufstein were analysed.

The analysis is based on high-resolution simulations using the numerical, physically based climate model FITNAH-3D, a mesoscale wind field model specifically designed for simulations in complex terrain. Simulated parameters include air temperature, Physiologically Equivalent Temperature (PET), as well as indicators of cold air production and cold air dynamics. For the first time in Austria, spatially continuous results for a region of this extent are available at a spatial resolution of 5 × 5 m, allowing the representation of small-scale climatic differences and processes.

The results indicate pronounced thermal stress in densely built-up and highly sealed areas of the valley floor. High heat loads during the day combined with limited cooling at night indicate a pronounced urban heat island effect. At night, cold air processes can contribute substantially to thermal relief in settlement areas, particularly during radiation nights with low atmospheric exchange.

Based on defined limit and threshold values, climatic hotspots within settlement areas were identified, allowing the prioritisation of adaptation measures. The analysis of cold air drainage pathways enabled the identification of climatically effective open spaces and slope areas as well as settlement edges sensitive to cold air processes. The preservation and consideration of these areas is essential for maintaining the functionality of cold air formation and drainage. The results therefore provide a technical basis for future land-use and development decisions in the Inn Valley.

Based on the analysis, measures for heat mitigation and for safeguarding climatic compensation processes were derived. Further integration with spatial planning and sociodemographic data will allow a more detailed assessment in the future. In view of increasing land-use conflicts, the analysis highlights the need to integrate climatic aspects early and systematically into planning and development processes in the Alpine region.