911±¬ÁÏÍø

70% of global carbon dioxide emissions are generated in cities. For almost three decades, densifying the urban structure along public transport routes has been seen as the most important land use policy method for curbing urban emissions.

In recent years, however, understanding of the importance of urban nature has increased. The EU's recently adopted Nature Restoration Law also highlights the importance of urban green space cover both in combating climate change and its impacts and in promoting biodiversity. 

Cooperation between cities and regions is important for finding solutions for sustainable development. Excellent examples of this are the CO-CARBON and SMARTLAND projects funded by the Strategic Research Council of Finland. In a recent study, researchers at 911±¬ÁÏÍø investigated how densification and greening are negotiated in the climate plans of Finland's six largest cities – Helsinki, Espoo, Tampere, Vantaa, Oulu and Turku.

'Cities play a significant role in climate work, and large Finnish cities in particular have been pioneers in climate work even before the legislative obligation,' says Professor Ranja Hautamäki.

The researchers found that even though the importance of urban green is growing, densification of the urban structure is still the focus of climate work. 

'It has become self-evident and a fact that is not questioned – even though it is always a question of political decisions,' Postdoctoral Researcher Tuulia Puustinen emphasizes. 

"Interestingly, the contradictions between compaction and greening were hardly highlighted in the plans."

In the climate plans, urban green was present mainly in three ways. The most traditional way is based on nature conservation: nature is protected as a counterbalance to densification, and urban green and built cities are seen as separate entities. This approach was strongly reflected in the climate plans of Tampere, Turku and Vantaa.

Another way is to see urban green as an adaptation method harnessed for densification, which helps, for example, in stormwater management. In their climate action plans, Helsinki, Espoo and Oulu emphasized adaptation in particular.

To the delight of researchers, the climate plans also included a third approach which does not rely on densification and in which urban green is seen as a complementary and even alternative strategy for densification. In this approach, urban nature is an integral part of urban development and, in addition to climate change mitigation and adaptation, highlights the many benefits of green for biodiversity and the well-being of city residents. In their climate action plans, multi-benefits were highlighted especially by Vantaa, Tampere and Turku.

Protection and sprinkling green is not enough

Urbanisation is a global megatrend that is also strongly visible in Finland. A third of Finns already live in the six largest cities, and the population of all the six is also projected to grow in the future. This further underlines the importance of urban climate actions, the researchers emphasize. 

Simply sprinkling the green here and there or protecting the green on the outskirts of the city is not sufficient for managing stormwater, cooling effects of vegetation or effectively sequestering carbon. In order to guarantee local climate benefits, tree canopy cover should be 30 per cent throughout the city, but in some districts of Helsinki, for example, it remains as low as 4 per cent.

Urban climate action plans have not previously been studied much in Finland. The researchers emphasize the importance of climate plans as a cross-administrative tool that reconciles the objectives of different sectors and takes into account the climate benefits of urban green and its significance for biodiversity. For cities, such an integrated approach requires thinking that recognizes potentially conflicting climate policy objectives and trade-offs and synergies in setting targets across policy sectors and the traditional mitigation-adaptation divide. 

The future of climate action plans is uncertain as the Finnish government has removed the obligation to draft municipal climate action plans, which was included in the Climate Act. Researchers hope that despite this, cities continue their ambitious climate work and further develop climate plan as a key tool to steer their climate actions. 

(sciencedirect.com)