After a month of June of record heat and an unprecedented heatwave suffocating the whole of Europe - with temperatures reaching 46 °C in Southern Spain - it’s clearer than ever that addressing extreme temperatures in our cities is an urgent matter. Rising heat stress is putting increasing pressure on our cities and towns, who suffer the most due to urban heat islands trapping and intensifying heat in urban areas.
At local level, extreme heat threatens public health, deepens social inequalities, makes our cities unliveable, and harms their economic vitality. Within the Covenant community, half of signatories in Europe have developed dedicated adaptation plans. Of these plans, an overwhelming majority – 86% to be exact – have identified “urban heat variation” as a specific hazard experienced in their plans.
Our latest #CitiesRefresh campaign aims to shed light not only on the risks of extreme heat for cities, but also on the possible solutions and the actions that many are already taking. The campaign encourages cities to “hit refresh” and reinvent themselves in the face of extreme heat – restoring healthy environments, improving quality of life, and redesigning cities so they remain safe and dynamic for everyone in a warming world.
Through the Covenant of Mayors, municipalities take an integrated approach to climate planning – dealing with mitigation, adaptation and energy poverty together. In this spirit, the campaign promotes a cross-cutting response to heat, integrating nature-based solutions with energy efficiency standards, energy poverty measures and public health policies.
Find guidance and tools on all these solutions in our recently launched Refresh Kit.
Refreshing Cities with Nature-Based Solutions
While each city brings its own context and challenges, one solution to heat emerges across the board: nature-based solutions. Many of our campaign cities’ actions to combat heat focus on integrating more vegetation and water into public spaces and city infrastructure.
In the Mediterranean and highly urbanised city of Marseille, streets and squares are being transformed with increased vegetation, turning hard, heat-absorbing surfaces into shaded, cooler zones. The city is also mapping cool itineraries – green and shaded pathways that allow residents to navigate the city more comfortably during periods of extreme heat.
Nature based-solutions & Cool Zones Map © Ville de Marseille
Cities like Guimarães are investing in connecting green spaces to create green belts throughout the city. This is also an approach used in cities globally, championed by Medellín’s green corridors, where they have developed 30 green corridors to expand the city’s canopy cover and cool the city while improving air quality.
To learn more on how to green your city for more shade, check out useful resources from our Refresh Kit on expanding your city’s tree canopy cover.
Meanwhile, Reggio Emilia has focused on improving the quality of their green spaces, to turn nature into a real ally faced with climate hazards. Their approach has been to reimagine its parks, creating a new model focused on biodiversity and climate-positive vegetation. So far, 12 parks have embraced this innovative approach.
Biagi Park: example of an adaptive park. 2023 © Municipality of Reggio Emilia
Another area that local governments can transform to be more resilient are municipal schools – especially important considering that children are amongst the most vulnerable to heat. Paris has reimagined school yards through its "cours oasis" program, greening 165 school yards since 2017, with the added benefit of opening them to the public during summer holidays—an approach echoed by Lille Metropole.
For more tips on nature-based solutions to green your city’s public spaces, check out this guidance on effective street tree and grass designs to cool European neighbourhoods.
Across many cities, water is also being thoughtfully reintroduced into public spaces as a passive cooling element, softening urban heat islands and revitalising community spaces. A Swimmable Cities Alliance was launched at the end of the 2024 Paris Olympics, including cities like Paris and Rotterdam, reclaiming urban waterways and restoring them to become healthy areas for citizens to refresh.
Maribor's main square on a hot summer evening. © Gordana Kolesarič
Refreshing Cities with Heat-Resilient Urban Design
Beyond public greening, cities are embedding passive cooling and shading into the core of urban design. Seville, facing some of Europe's hottest summers, is redesigning streets and public spaces using both modern techniques and traditional wisdom to improve environmental comfort and promote social life regardless of temperature. In Rethymno, Greece, bioclimatic design is being implemented in public spaces, incorporating the use of compressed soils, cool pavement and reflective road paint.
Rethinking our buildings – often not fit for hot temperatures – is key to making our cities more liveable and protecting citizens, especially in vulnerable neighbourhoods. For this reason, Getafe is placing summer thermal comfort at the heart of its building renovation strategy, part of their Hogares Saludables (“healthy homes”) programme. This includes improved insulation, green infrastructure, and passive cooling, particularly in low-income neighbourhoods and vulnerable populations.
© EMSV Getafe - Getafe City Council
For more on making buildings heat-resilient, dive into the European Commission’s Technical Guidance on Adapting Buildings to Climate Change, part of our Refresh Kit.
To cool down buildings, cities are also incentivising the integration of nature-based solutions within building and infrastructure design through dedicated strategies, financial incentives and building codes.
Madrid – with average temperature above 30 degrees and regular highs in the 40s in the summer – has just passed a plan to turn disused rooftops into lush gardens. Similar approaches are already underway in Rotterdam, which has had a green roof strategy – in line with their adaptation strategy – since 2008. Financial incentives have been put in place to encourage developers to invest in green roofs and transform the rooftops of the city into key areas of resilience.
The city of Hamburg has a similar strategy, with the goal to install a total of 100 hectares of green roof surface in the metropolitan area. The city subsidises 30 to 60% of the costs of voluntary greening measures and intends to make green roofs and green façades compulsory by law for all suitable buildings. Vienna is experimenting with integrating greenery into the very fabric of its infrastructure, from green islands to shaded bus stops, improving residents’ comfort as they move around the city in times of heat.
A completed climate-adapted bus stop with a green, vibrant roof, also supporting biodiversity © Wiener Linien
For guidance on cool roofs and buildings, check out this practical guide in our Refresh Kit.
Refreshing Cities with Smart Local Governance
While long-term urban redesign is crucial, many cities are also prioritising more immediate measures to protect vulnerable populations during heatwaves. Governance is evolving to include tools like heat mapping, heat health plans, and targeted diagnostics to identify the most exposed areas like the ones developed in the Slovenian city of Maribor.
To prepare your heat map and a heat action plan, check out this Thermal Assessment Tool and resources from the Atlantic Council’s Heat Action Platform.
Getafe, again, leads in tackling summer energy poverty with a dedicated strategy, leading to targeted interventions that make the most vulnerable households more resilient to heat. In Valencia, a network of climate shelters – usually cooled municipal buildings open to the public, such as libraries and the city’s energy offices – has been established to provide safe spaces during extreme heat.
Example of Climate Shelter on the Climate Change Observatory © Valencia Clima I Energia, 2025.
For more resources on summer energy poverty, check out Cool2Rise's Policy Recommendations.
Public awareness is central to a city’s preparedness to respond to heat. Athens – which also suffers from extremely hot summers with many days around 40 degrees – has been a pioneer in this area, being the first to appoint a Chief Heat Officer to spearhead efforts to promote heat-safe behaviour and protect citizens in case of a heat wave.
They categorise heatwaves based on how dangerous they are and when run city-wide campaigns to disseminate safety tips, while also mobilising assistance for vulnerable populations. To sound the alarm around the dangers of heatwaves – and bring them to the level of other climate disaster in public consciousness – Seville was the first to name a heatwave with “Heatwave Zoe” in 2022.
For tips on communication and raising awareness around heat, check out C40’s Home Cooling Tips messaging toolkit.
In Rotterdam, a city relatively unaccustomed to heat, the use of Heat Action Day on 2 June to increase understanding of the dangers and risks of heat for everyone. They use this day as a magnet around which to mobilise communities, organisations and institutions – including the national government which, for the occasion, developed its first ever National Heat Approach – and spark action at neighbourhood level. As a result, districts have started to put in place heat protocols to protect communities in case of a heatwave.
National and regional level legislation is critical to support cities’ efforts. In Apulia, a regional emergency was declared in the wake of a 2022 heatwave and a law introduced to protect outdoor workers from the dangers of heat. Early warning systems are another critical tool to prepare the local level to respond to heat – yet only 21 of the 38 EEA countries currently report having them, prompting some cities and regions to develop their own local alert mechanisms.
Refreshing Cities with Community-Driven Solutions
Finally, community engagement has proven essential in the climate adaptation process. As highlighted above, public awareness around the risks of heat is crucial to enhance cities’ preparedness in the face of heat. Meaningful public engagement can boost this awareness, extend help networks to those in need, and accelerate the necessary transformations to make cities more liveable and safer.
Cities like Getafe are establishing one-stop-shops to streamline home renovations as part of their Healthy Homes programme and running workshops in the neighbourhoods where regeneration efforts are taking place in the buildings and public spaces. In Lviv, Ukraine, and many other campaign cities, communities have been at the centre of greening efforts – mobilising communities to transform their own public spaces.
© The City of Lviv
The city of Worms is running workshops on what to do when temperatures rise tailored to children and outdoor workers – two groups especially vulnerable to heat. In many cities, local organisations are being mobilised to map out vulnerable citizens and provide on-the-ground support, like in Strasbourg, ensuring no one is left behind in times of heat.
Studies have shown that robust social infrastructure – relying on a neighbourhood’s existing community networks and shelter, like churches or mosques, health organisations and local businesses – can make the difference between life and death when a heatwave hits.
Ready to hit refresh in your city? Explore our Refresh Kit to get started!
To guide you in finding the right solutions for heat in your city, we've put together a Refresh Kit that’ll help you navigate the existing resources out there. Whether you're just starting or refining your approach, you'll discover practical guidance, inspiring stories, essential tools, insightful publications, and much more.
Dive into the Refresh Kit.
Üksikasjad
- Avaldamiskuupäev
- 30 June 2025