Heat hazard indicators in the metropolitan area of Turin, Italy

Heat waves are becoming more frequent and intense due to climate change, posing significant threats to urban environments. The Urban Heat Island (UHI) and Urban Dry Island (UDI) effects exacerbate these impacts by increasing local temperatures and decreasing moisture compared to surrounding rural areas. This study focuses on the metropolitan area of Turin, Italy, leveraging observational data to characterise the UHI and UDI phenomena and identify urban areas most at risk from extreme heat events.

20 years of hourly data coming from the ground network of ARPA Piemonte are analysed to map thermal and moisture patterns within the city. The analysis reveals intra-urban areas where the combination of population density, urban morphology, and temperature or moist anomalies heightens vulnerability to heat waves.

This work aims to support climate change adaptation strategies by providing essential information for risk assessment and urban planning. Identifying heat-vulnerable areas enables the design of targeted interventions, such as creating green infrastructure, urban cooling strategies, and implementing heat alert systems. The results underscore the importance of observational data in developing climate services tailored to urban environments, where localised phenomena like UHI and UDI require precise monitoring and targeted solutions.

The findings provide valuable insights for policymakers and urban planners to enhance climate resilience in urban areas. The proposed approach serves as a replicable model for other cities facing similar challenges, fostering proactive adaptation to the rising hazard of extreme heat.

This research is conducted within the framework of RETURN (Multi-Risk Science for Resilient Communities under a Changing Climate) project, funded under the Italian PNRR (Piano Nazionale Ripresa e Resilienza - National Recovery and Resilience Plan), as part of the Spoke 8 DS - Science Underpinning Climate Services for Risk Mitigation and Adaptation.