There is a strong link between the urban climate conditions and the land use structures of cities.
Dense concentrations of impervious artificial surfaces, such as buildings, roads, pavements etc. – typical of urban landscapes – generate higher atmospheric and surface temperatures, creating ‘urban heat islands’, i.e. urban areas with significantly higher temperatures than in the surrounding rural areas.
However, the presence of green areas, pervious surfaces and water bodies can in contrast influence the climate conditions of the city very positively. The presence of green areas, such as parks or trees, in the city has a strong cooling effect on the local climate – thanks to the evapotranspiration process, vegetation absorbs heat, increases local humidity and it also provides a shade, which is very desirable during hot summer days in the city.
Therefore, effective and environmentally friendly urban planning and decision-making play a key role in the mitigation of urban heat islands.
City authorities are aware of this correlation and are making considerable efforts to mitigate urban heat through sound urban planning. Many cities are already preparing their climate change adaptation strategies.
To ensure environmentally friendly urban planning decisions, there is a need for high-quality and reliable scientific information about the impacts of urban planning decisions on the urban climate. However, such information is still missing in many cities.
The Climate-fit.city urban planning sectoral service will make this information available to decision-makers. An interactive climate service will be developed, which will enable city decision-makers to assess the impacts of different urban land use development scenarios, reflecting on the consequences of various urban planning strategies on the climate conditions in their cities.
The benefits of using the service is being demonstrated in three cities in the Czech Republic: Prague, Ostrava, and Hodonin.
The city of Prague, a large capital city with more than one million inhabitants, is searching for scientific support for their climate change adaptation strategy. The impact of the urban development strategies, as they are currently being prepared by the city administration, on the city’s climatic conditions will be explored and assessed. First, modeling will be applied at the level of the entire city, second, a high resolution climate model will be prepared for a selected smaller area inside the city, in which substantial urban development is expected in the near feature.
The situation is similar for the city of Ostrava, which also has a climate change adaptation strategy in preparation. Most of all, Ostrava needs to model the effect of three large ‘heat heaps’, located in the city centre, on local climate. These heaps are the residuals of former mining activity and are still burning inside, emitting gases like methane and sulphur dioxide and with inner temperature reaching over 1000 °C.
The third city, Hodonin, will help to demonstrate the potential of the urban planning service for smaller cities, for which maximum level of spatial detail is crucial. The Hodonin city is developing its local climate adaptation strategy and to support this process scientifically, the urban planning service will model the impact of changes planned in a small area in the city, where significant development of the urban structure is about to occur.
The Climate-fit.city’s urban planning service provides a unique combination of the urban climate model UrbClim, developed by Belgian research and technology organisation VITO, and an interactive web-based map tool developed by the Czech geoinformation company GISAT.
The web tool will serve as an online presentation and communication platform, enabling stakeholders to explore, analyse or even modify the temperature maps in time series, generated by the UrbClim model, in an interactive and user-friendly way.
The temperature maps displayed in a multi-temporal map window will be accompanied by synchronised charts and tables, which will facilitate highly interactive user-driven analysis of climate conditions in the cities and their development.
In addition, the platform will provide the user with a possibility to re-calculate the temperature maps, through modification of the land use structure of the city. This will enable the user to play with different scenarios of the city development in the future, which can correspond to various urban planning strategies.
The Copernicus Urban Atlas is used as the main source of information about the urban land use structure, which secures full comparability of the results across European cities. This harmonised land use database is currently available for most of EU28 and EFTA cities with over 50,000 inhabitants.