What can northern cities do to combat increasing heat?

Estonia's capital city Tallinn is grappling with a new challenge - rising temperatures and more frequent heatwaves. While not known for extreme heat, climate change is bringing new weather patterns that are pushing the city to adapt. ?Heatwaves will become more frequent, longer and more intensive", explains Airi Andresson from Tallinn's Strategic Management Office. She notes that in recent years, temperatures around 30°C, once rare, are occurring more often.

Adaptation comes in tiny steps

For Tallinn, that already turns out to become a problem. Temperatures above 27 or even 30 degrees were seldom the case in the past. Now that heat is on the rise, the existing infrastructure from cooler periods is proving inadequate. Apartment blocks and streets are not constructed forever prolonging heat waves. Something hard to change in a few years says Andresson: ?We already did a pilot project, to plant larger trees where new streets are constructed. They provide shade instantly.“ But already existing streets are not adapted as easily. The same counts for renovations of apartments. If a renovation is done, the ventilation has to be considered, too. But the renovation rate of cities in Europe seldom exceeds 2 percent. So adaption comes in tiny steps.

The most essential problem for Tallinn is the lack of data: "We don't have a sensor network of the whole city“, says Andresson. The city management can therefore not plan according to the microclimate in the city: ?This is something that we need to work on“, says Andresson. The good thing, though, is that Tallinn introduced a digital twin a few years ago. "If we can generate more data, it is possible to put it on the digital twin so that in the future, we will know the microclimate around planned projects.“

Building green and blue infrastructure

Another idea, which comes from places with a longer history of heat are so-called cooling centers: "If it's extreme heat and certain people who aren't able to stay indoors in their apartments, they would have a place for free where they could go, where there would be water available and maybe even some medical aid. A pilot project with three cooling centres will be available as of 29th of July and they will prepare a crisis management plan for extreme heat by next year. With the new crisis plan, we will create a preparedness for more cooling centres."

Of course, there is not that magic one solution that will fix all of Tallinn's problems but the increased green and blue infrastructure poses a very important step towards a cooler and more livable city: "Basically what we're hoping to achieve is, that there would be a green area accessible within a certain distance,“ says Andresson. Green areas should then also be connected to make green paths in the city possible.?

How KNOWING can support Tallinn's adaptation to heatwaves

The KNOWING project can help cities like Tallinn adapt to the challenges posed by rising temperatures. By developing a comprehensive modeling framework, KNOWING assists in understanding and quantifying the interactions between climate change impacts, mitigation pathways, and adaptation strategies. For Tallinn, this could mean using the KNOWING knowledge database and pathways to find the best ways to handle heat waves and strengthen infrastructure.