Supporting site selection for a meteorological monitoring network in the City of Linz (Austria)

The City of Linz identified heat stress as a strong climate hazard for its inhabitants. To improve knowledge about local characteristics of heat stress, potential measures, and its consequences, a meteorological monitoring network, focusing on the parameter air temperature is to be implemented. The network will consist of approx. 50 monitoring stations optimally placed with respect to several requirements: (1) representative measurements for similar regions within the city area, (2) show the variety of urban microclimate conditions, (3) include strategically reasonable sites, (4) use available mountable infrastructure (masts, public buildings) and (5) represent extreme conditions within each similar region.

An innovative research design identified a set of well-suited locations for the monitoring stations, incorporating established methods and approaches in urban climate research. It considers the following elements: (i) calculation of an urban climate simulation with PALM for a typical summer day with a spatial resolution of 10 m providing the data about heat stress conditions in the city, (ii) application of the concept of Local Climate Zones (LCZ) to define similar regions in the city, (iii) consideration of locations for potential mountable infrastructure, (iv) definition of a set of criteria for sites in each LCZ (e.g. low nighttime air temperature, sun exposure).

Performing aforementioned steps confirms that PALM is well-suited for simulating entire city areas to depict local meteorological characteristics. Further, combining the concept of LCZ with PALM output provides valuable insights into the effect of small-scale difference within the same urban typology. Incorporating the local knowledge of the participating department of urban climatology and environment ensured the applicability of the gained results. The study provides an illustrative example of how city-scale urban climate simulations deliver valuable data to support practical challenges of city management, and further highlights opportunities and benefits of close cooperations between local decision-makers and research institutions.