Many European cities are experiencing extremely high temperatures this summer – a trend that municipalities are accepting will continue. According to findings by RAMSES researchers, there will be 10 times more heat wave days from 2081-2100, reaching nearly 30 heat wave days per year on average.
A study by RAMSES related to the 2003 heat wave in France found that while heat waves coincided with an increase in deaths in small towns, Paris, as a major city, suffered nearly three times the number of additional deaths during heat waves.
Why do cities tend to be warmer than their rural surroundings? Firstly, there are more buildings and soil sealing: buildings store heat during the day and release them at night. Walls cause additional radiation as they reflect the sun’s rays and reduce ventilation in narrow streets. Secondly, cities cool less due to less vegetation in city centres causing lower evaporation levels. Thirdly, humans create additional heat, such as through vehicle exhaust. The maps produced following a study in Antwerp and 101 other European cities show where in cities the highest temperatures are occurring and which areas should be prioritised for adaptation measures.
The project found that a typical western European city has a mean temperature difference at midnight of around 4oC . City temperatures on hot summer nights are 8oC -10oC higher than rural areas, as a result of less ventilation and higher populations. The RAMSES project is now completing its fifth year working with cities to promote adaptation, mitigation and sustainable development. The project is currently holding a series of free webinars, which will continue on 13 July.
For more information and to register, click here.