The urban population continues to grow globally, which, in combination with hazards becoming more frequent due to climate change, increases the vulnerability against climate risks. Reducing greenhouse emissions are no longer enough to halt climate change impacts and there is a pressing need to adapt cities to a warming climate.

Cities have implemented a wide variety of different soft and hard adaptation measures, such as building flood defence walls, establishing green infrastructure and installing air conditioning. Unfortunately, many of these adaptation measures themselves result in an increase in consumption of materials and resources, ultimately increasing greenhouse gas emissions. As cities continue to respond to the many challenges imposed by climate change, this complex coupling between mitigation and adaptation is likely to increase.

In its national strategy for climate change adaptation, the Swedish government highlights, among other things, that adaptation measures should aim to support mitigation efforts and vice versa. Despite these efforts, the coupling between mitigation and adaptation continues to exist. Can circularity possibly bridge mitigation and adaptation?

The role of the circular economy in climate mitigation

A circular economy makes use of various strategies such as reducing, reusing and recycling that together eliminate waste, lower material and resource consumption and reduce greenhouse gas emissions. There is a link between the circular economy and climate mitigation and transitioning to a circular economy can arguably mitigate carbon dioxide emissions that emerge from extractive industries, manufacturing, construction, transportation and other sectors. In the building sector alone, circular economy actions are estimated to cut emissions by up to 61%. The Swedish government recognizes this potential and has consequently added the circular economy as a key priority in its climate policy action plan. At the more local level, the Hammarby Sjöstad area in Stockholm is one example that has managed to reduce greenhouse gas emissions by aiming to close its energy loop through various strategies, such as generating electricity from household waste and transforming water treatment sludge to biogas.

Can climate change adaptation be circular?

Climate change adaptation can also be circular. In the context of cities, urban planning offers great opportunities for both circularity and adaptation. A notable example is nature-based solutions that entail integrating green infrastructure and ecosystem services into the built environment to further boost resilience. The city of Stockholm has integrated trees and green areas into city planning in order to reduce the impact of heatwaves, while also managing surface water and biodiversity as well as enhancing social values in the built environment. Nature-based solutions can be circular if they use renewable resources, reuse or repurpose other resource streams and avoid unwanted by-products. Nature-based solutions also make adaptation measures circular and smarter by promoting multifunctional areas in cities. For example, green spaces in Stockholm are used for both heatwave protection and recreational activities. 

Adapting the built environment in cities can even be a circular strategy in itself, as it can reduce future resource consumption. As recently highlighted in an op-ed in the Swedish newspaper Expressen, climate-induced disasters can cause significant damage to buildings and infrastructure, resulting in construction and the consumption of new materials, thus causing additional greenhouse gas emissions. Like the rest of Europe, Sweden was plagued by cloudbursts in the summer of 2021. Gävle was particularly affected, with over 700 reports of damage valued at almost SEK 500 million, indicating an increase in construction and consumption.

Circularity plays an important role in building resilient cities

It is crucial to take a holistic approach when addressing climate risks in order to avoid actions that increase vulnerability rather than decreasing it. Cities can serve as a catalyst, leading the way in applying circular economy principles in their work with mitigation and adaptation. Ultimately, the potential of circularity in mitigation and adaptation calls for further attention in working towards a more sustainable and resilient future in cities across the globe.