High resolution modelling of the urban heat island of 100 European cities

In urban areas across Europe, high air temperatures and urban heat islands (UHIs) greatly affect public health, with climate change further increasing the mortality risks. This study presents a validated high resolution (100 m) hourly air temperature dataset for 100 European cities for a 10-year period (2008–2017) that is made available for urban climate research. The data is used to analyse the UHI (as defined in this study) of these 100 cities, using a dedicated indicator that is suitable for comparison across Europe. The UHI indicator is found to be correlated to both meteorological and urban characteristics. Using a statistical model, the current and potential cooling of green infrastructure and soil unsealing in the 100 cities is quantified. The Europe-wide current impact of these climate adaptation measures on the UHI indicator is found to range between 0.03 and 1.82 °C (with an average value of 0.45 °C), which is significant compared to the UHI indicator values ranging between 0.57 and 2.54 °C (with an average value of 1.43 °C). Nevertheless, a large potential for extra cooling from such measures is found to remain in many cities, ranging between 0 and 1 °C, with the Europe-wide average value being 0.49 °C, slightly higher than the estimated current cooling.