Copernicus to mitigate the urban heat islands in Prague
Heatwaves are among the most intense consequences of climate change, with record-high temperatures occurring more frequently. Extreme heat is a particular concern in urban areas, where the “urban heat island” effect causes city centers to be significantly warmer than surrounding rural areas – on average 4-6 degrees warmer, and with peaks up to 10 degrees above neighbouring areas. Factors such as the lack of green spaces and waterways in cities coupled with sealed surface (e.g. roads which absorb heat during the day, releasing it at night), the low ventilation and high density of people contribute to increased heat in city environments. In Prague, this phenomenon is intensified due to densely built-up areas and industrial infrastructure, making the city more vulnerable to extreme heat events.
To assess extreme heat vulnerability and identify ways actions to mitigate “urban heat island” effects on public transport users in Prague, researchers utilised Earth Observation data in addition to other data sources. A thermal exposure analysis was conducted using Landsat 8 satellite images from NASA, taken during the summers of 2015 to 2019. This data allowed researchers to identify the hottest areas in the city, particularly on days when temperatures exceeded 30°C.
In parallel, the city’s resilience to heat, or its “adaptive capacity,” was evaluated by mapping green spaces and water bodies near public transport stops. This analysis relied on data from the Copernicus satellite, specifically the Advanced Vegetation Index and the Normalised Differential Water Index.
By combining this information with data on average waiting times at transport stops, an urban heat vulnerability map for Prague was created. This map allowed city officials to pinpoint the most at-risk areas. As a result, public transport stops were upgraded with heat mitigation measures, including green roofs, misting devices, and water fountains at the most affected stops.
This project showcases how Earth Observation data, such as those from the Copernicus program, can be used effectively to combat the urban heat island effect and protect public transport users from the growing impacts of climate change.
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