Six municipalities join forces to combat increasing heat in cities

Since summer 2023, six municipalities from Germany, Kenya, Egypt, Morocco, and Ukraine have been working together on solutions to better protect their populations from heat and reduce the increasing heat islands in their cities.

The participants of the Deep Dive in Heidelberg | Photo: Philipp Rothe

From 3 to 6 June 2024, the group came together in Heidelberg as part of the “Connective Cities Deep Dive” to substantiate their pilot projects and learn from the experiences of other cities.

Although the six cities have to adapt to increasing heat in different ways, they have two principles in common, as became clear during their exchange in Heidelberg. If you want to do something strategically and in the long term to combat heat in cities, you need a plan. This is just as true for Aswan in Egypt, where temperatures can reach 50 degrees Celsius in summer, as it is for Lüdenscheid, which is located in the cooler, densely wooded Sauerland region of Germany. They also strongly believe in the approach of initially testing innovative heat solutions in small pilot projects before implementing them on a larger scale.

There are many ways for cities to reduce the negative heat effects on the population: creating more green spaces, planting shade-providing trees, greening building facades, creating cooling corridors, for example through watercourses, raising public awareness and much more. To do this, it is first important to know where the heat builds up in a city.


Pilot projects: From new trees to the framework plan

During the workshop in Heidelberg, the participants developed action plans for their strategies and pilot projects. The goal is to have their pilot projects implemented by the end of the year. In Nairobi, Kenya air temperatures are measured in various schools. Based on this data, shade-providing fruit trees will then be planted at selected schools and staff will be made aware of the issue of heat. In Lviv, Ukraine the population is to make suggestions for the creation and design of mini-parks to reduce the heat, which the city will then implement in public spaces. Here, too, the temperature is to be measured over a longer period of time in order to obtain data on the cooling effects of the measures implemented. To accomplish their long-term goal of developing a heat action plan for their cities, Lüdenscheid (Germany) and Aswan (Egypt) have identified the necessary steps of 1) establishing a core working group with the most relevant departments to be involved in the process, and 2) developing the general framework and selecting a zone for piloting respectively. Similarly, participants from Mombasa have developed an action plan for their pilot that aims at raising awareness among stakeholders and citizen on urban heat islands and its effect as well as to mapping urban heat island hotspots in the city.

Host City of Heidelberg presented its work

The presentation of the Heidelberg Heat Action Plan was of particular interest. With this plan, the city aims to protect vulnerable population groups from the negative effects of rising temperatures in the city in the short and long term. Dr. Raino Winkler from the City of Heidelberg reported on the “Mediterraneanization” of the climate, which would result in more tropical nights, among other aspects. Part of the heat action plan was the creation of a "cool map", said Winkler. It shows cool places and free drinking water points on the city's website. During a visit to Bahnstadt in Heidelberg, a new district with around 3,700 new “passive houses”, Winkler explained to the group how public spaces there have been designed and planted with greenery to reduce the heat load on the population in summer. As part of this visit, the participants have met Dr. Katrin Foshag who is leading the TdLab Georgraphy at Heidelberg university. A project conducted by a Master student was presented, which focuses on assessing the perception of thermal comfort by the users of public spaces compared to actual thermal measurements collected via sensors.

The participants received expert input from Prof. Dr. Jürgen P. Kropp from the Potsdam Institute for Climate Impact Research (PIK), who is providing long-term scientific support for the Deep Dive. He pointed out that a lot of weather and climate data is freely available worldwide. Although their resolution is not ideal, it is often sufficient as a basis for developing measures to combat heat and heat islands.

Benefits of the Deep Dive process clear at the halfway point

This workshop was the seventh meeting of the group and the third in person, following events in Bonn and Lüdenscheid at the end of 2023 and in Nairobi in March 2024. The next workshop is planned for January 2025 in Aswan. The final step of the Deep Dive will then involve evaluating, improving and scaling up the pilot projects implemented up to that point.

The six municipalities are taking part in the almost two-year deep dive because they can learn a lot from each other despite their different starting points. For example, all participants in Heidelberg enthusiastically embraced the idea of involving universities, which often have more comprehensive climate and weather data, more closely in their own work and initiating university cooperation in this field. It also became clear that anyone developing a municipal heat strategy does not have to start from scratch. There are many examples from other cities that can provide inspiration and ideas. Finally, the participants realized that they all need to find ways to convince other administrative departments and politicians that measures to combat heat are becoming increasingly important. The strategies for doing this are similar around the world. Sharing good experiences in one place can prevent mistakes in another.

The cities of Lüdenscheid and Heidelberg (Germany) as well as Aswan (Egypt), Nairobi (Kenya), Lviv (Ukraine) and Benguerir (Morocco) are taking part in the Deep Dive. The delegation from Benguerir (Morocco) was unfortunately unable to attend the event in Heidelberg.

-> More about Deep-Dive „Heat in the City”

Ayan Huseynova, Connective Cities