Bridging Gaps in Urban Climate Mapping: An Open-Source based Framework for Climatope Identification

Climate mainstreaming requires the planning sector to consider policies and directives to enhance climate-resilient urban planning. In several cities of Germany and Austria, urban climate maps (UCM) provide substantial scientific information for city administration, containing two key components: an urban climatic analysis map (UC-AnMap) and a planning recommendation map (UC-ReMap). While based on the VDI (Association of German Engineers) directive 3787, many existing methodologies suffer from significant limitations: (1) lack of standards and comparability, (2) high development costs, and (3) insufficient trust in the provided data and maps for planning decisions due to poor documentation or lack of understanding of approaches and results applied.

The research project "OSCAR - Objectifying and Standardizing Urban Climate Analyses for Climate-Resilient Urban Planning" (funded by the Climate and Energy Fund and carried out under the program "Austrian Climate Research Programme (ACRP)") addresses critical challenges and aims to provide solutions through a comprehensive approach. By engaging stakeholders including urban climate modeling experts, consulting agencies, and city representatives through expert interviews and workshop formats, the research unites a theoretical foundation with practice-oriented expertise.

A central objective is the creation of an objectified model for UC-AnMaps to (i) accelerate urban climate condition assessments, (ii) enable quantifiable climate adaptation measures, (iii) facilitate comparative urban climate analyses and (iv) provide robust climate analyses for planning recommendations. The proposed methodology leverages publicly available data and open-source software, utilizing weighting of static input data sources (e.g. imperviousness density), a rudimentary cold air flow algorithm, logical spatial data combinations and subsequent assignment of climatopes.

The approach focuses on a VDI-conformal, transparent method for mapping urban climatic conditions. Preliminary findings demonstrate promising potential for scaling and expediting UC-AnMap developments. Importantly, stakeholder-engagement emphasizes that while the method provides crucial quantified urban climate information, it should complement—not replace—consultative processes in developing planning recommendations.