Viennese heat islands: new solutions for cooling required!

Viennese heat islands: new solutions for cooling required!

A research team from the Boku University deals with the effects of longer heat waves in the Vienna area in his project. The study in particular illuminates the problem of urban heat island, which leads to higher temperatures in densely built -up areas, especially at night. The causes of this are varied: dense buildings, sealed areas, the lack of vegetation and additional heat sources such as traffic, air conditioning systems and industry contribute to overheating. This restricted nightly cooling is a significant challenge for the human organism, since it affects the necessary recovery, how [Oekonews] (https://www2.oekonews.at/boku- research project- show-and-limits-staedtischer-Abkuehung-Begruung-Bewaessenung-und-Photovoltaic-on+2400+128115) reports.

The environmental protection department of the city of Vienna has dealt with urban climate issues since 2001 to promote climate change -adapted city designs and increased summer comfort. A large number of measures to combat urban heat islands was developed to improve the city climate. This includes the analysis of weather data and the evaluation of urban projects in order to better understand heat-related emissions and their effects on the micro and urban climate, according to the city of Vienna on its website.

research approaches and tried and tested measures

The research team has examined various temperature reduction measures. This includes targeted irrigation of green roofs, parks and agricultural areas to optimize the evaporation cooling. The approach shows promising results: Targeted irrigation in the Marchfeld could reduce local temperatures by up to 3 ° C, while the cooling in the urban area is only about 0.2 ° C. But it also becomes clear that a considerable water requirement of 630,000 m³ per day would be necessary, while the high source lines can only provide 375,000 m³. It is recommended to develop sustainable irrigation concepts that use rainwater or Danube water, for example, to effectively support the greening of the city.

In addition, the use of photovoltaics on green roofs could not only reduce fossil electricity imports, but also reduce heat emissions. The maximum implementation of a solar strategy on the roofs could favor a cooling of up to 1.5 ° C. Such measures are part of a necessary mix of measures from urban planning, energy policy and resource conservation to make cities in Heatfit.

innovative greening concepts and their goals

Another innovative project to improve the city climate in Vienna are edible balcony gardens that include retrofitting balconies and integrated vertical gardens. These concepts aim at an increase in quality of life, biodiversity and adaptation to climate change. For example, organic buns made of sewage sludge in the Greenchar project are also used to give rooftops a better microclimate and reduce the urban heat islands. The Streetree project is also examined to plant city trees in heavily built -up areas with many underground lines. The aim of these measures is to expand the quality of stay and biodiversity of the city, as shown in detail on the BOKU website.