An open-data based framework for identifying spatial patterns of heat stress by synthetizing climatopes and local climate zones

The urban climate map (UCMap) and Local Climate Zone (LCZ) are the most popular conceptual frameworks for urban climatic evaluation and application. The UCMap is a planning-oriented tool for visualizing climatic issues spatially and offering guidelines, while LCZ illustrates the correlation between urban geometric morphology and its climate characteristics. However, they differ in data sources, classification standards, and planning implementation. This study uses Guangzhou, a subtropical high-density city in southern China, as a case. Firstly, an open-data-based workflow is established for delineating the Climatope-map (a representative of UCMap) based on the German standard (VDI 3787-Part 1) and LCZs across the city in a resolution of 100 m. Then, a hybrid climatope-LCZ map is developed by synthesizing these two systems spatially. The resultant map reveals marked variations in both land surface temperature and apparent temperature across the zones after comparing with climatic datasets. Approximately 5.93 % of Guangzhou's total area is identified as having a high heat stress hazard. This hazard is predominantly concentrated in the city center, urban subcenters, and industrial clusters, characterized by high-rise urban morphology, namely LCZ in 1/2/3. Finally, a set of urban climatic planning recommendations for various synthesized zones is proposed according to the guidelines in VDI 3787-Part 1. This study not only offered a feasible workflow for developing a hybrid climatope-LCZ map in a data-poor region but also exhibited the capacity of the map for rapid and precise heat stress hazard assessment, which will be a valuable tool for supporting stakeholders in responding to the challenges from climate change.