More grass instead of stone

Viennese cemeteries could cool the city climate

Vienna's cemeteries could become the city's air conditioning systems.(Bild: APA/MAX SLOVENCIK)

With green graves instead of granite slabs or perhaps even forest cemetery areas, the final resting places in Vienna could provide a more pleasant climate all around, explained meteorologist Marianne Bügelmayer-Blaschek on the fringes of the Climate Day Congress in Vienna. According to the meteorologist, the residents of the surrounding streets would experience a reduction in temperature of up to one and a half degrees as a result of the gravesites. At the suggestion of the Vienna cemeteries, she determined their cooling potential.

The researcher from the Austrian Institute of Technology (AIT) took a closer look at two very different burial grounds in Vienna: The cemetery in Meidling, which has many green areas and trees, where hamsters live and people not only find their final resting place but also seek relaxation, and the cemetery in Sievering, where larger areas are sealed by asphalt paths and gravestone slabs, for example. Using mathematical models and microclimate simulations, she calculated how much the conditions in the cemeteries influence the temperatures there and in the surrounding area.

Up to one and a half degrees cooler
According to Bügelmayer-Blaschek, the Meidling cemetery has shown that it can cool the surrounding areas by up to one and a half degrees Celsius. Even an average cooling of around one degree Celsius shortens heatwaves by around one day, reduces the number of tropical nights, ensures a better quality of sleep for residents and lowers the heat-related summer mortality rate, according to her project report. A forest cemetery could also be built in the Meidling area. According to the model calculations, it would then be three degrees cooler in the afternoons than the surrounding area.

The Sievering cemetery, on the other hand, currently even contributes to a warming of the surroundings, said the researcher: "This effect can be reduced or even reversed by unsealing and greening." Then this resting place would also contribute to cooling the environment. The cemetery administration also provides financial incentives to encourage Viennese to choose green graves instead of granite-sealed graves. "You have to pay a little more for a stone slab," reported Bügelmayer-Blaschek.