Fulfilling the requirements of the EU’s Nature Restoration Law in urban areas will require not only planning and administrative action but also citizen engagement. The paper at hand analyzes citizens’ willingness to change the urban environment in a study consisting of a pan-European survey with an integrated choice experiment. The majority of the 7045 respondents would support a rapid urban greening process and are willing to contribute to its financing. The latent class analysis reveals four different classes with different interests and willingness to engage: Class 1 supports the development of green areas and nature-based solutions in general and under nearly any conditions; Class 2 is sensitive to costs and accessibility disruption. For Class 3, participation will increase their interest and willingness to pay. Only Class 4 (8.6% of sample respondents) is against or disinterested in the development of urban greening. The findings demonstrate that the European goals are strongly supported by the majority of urban residents and highlight a significant interest in their implementation, to which they are also willing to contribute. These findings should encourage local initiatives and the local administration to implement the process of urban greening and the goals of the nature restauration law in a more ambitious manner.

Nature-based solutions are part of climate adaptation plans in many European cities. In recent years much research has been conducted supporting the effectiveness of urban nature-based solutions, however previous studies also have shown that multifaceted aims are difficult to achieve. Potential environmental benefits have to be balanced with related costs and spatial requirements environmental. These trade-offs underline that planning urban nature-based solutions involves choices. Therefore, this research builds upon a discrete choice experiment (DCE) which was conducted in 6 European countries focusing on cities with more than 20,000 inhabitants. The presented study, which was based on research as part of the UPSURGE project (Horizon 2020), sought to understand European urban residents’ preferences for urban nature-based solutions. The survey presented trade-offs such as the type of green area, the effectiveness in terms of air-quality, temperature reduction and biodiversity as well as monetary and time payments to participants. In total 5,990 residents from Greece, Poland, Hungary, Slovenia, the UK and the Netherlands participated in the survey. The results show generally similar patterns of preferences across citizens from all 6 countries regarding type of nature-based solutions and their effectiveness. Yet, different exposures to the impacts of climate change are reflected in the preference for effectiveness of the green areas for instance regarding temperature reduction. Furthermore, differences in preferences regarding the willingness to pay, biodiversity enhancement and participation are evident between the countries. Transferring the obtained results in a decision support tool, allows for the configurations of nature-based solutions which will be accepted by the majority of population in European countries. Overall, the results emphasize the need for customization of nature-based solutions to the local context and importance of communicating the expected benefits. Incorporating the results in public participation processes, enables the definition of priorities and the design governance mechanism to guarantee long-term success of nature-based solutions.

Towards the end of the 19th century, dense and urbanized European capitals were developed under the Austro-Hungarian empire. Most of the historically built-up areas are important for cultural heritage, they are now a challenge for heat reduction and urban planning. In Vienna and Budapest, the local populations are facing growing climate change impacts in the form of heatwaves and tropical nights. Nature-based solutions (NBS) are being eyed as measures to tackle urban heat islands and address the unequal distribution of green areas.The cities of Budapest and Vienna are comparable in terms of geographical area, population and climate zones. The urban morphology of the cities is understood by using Local climate zones to understand the thermal zones formed in the city. Vienna has a higher percentage of compact urban form as compared to Budapest in the city centre. The composition of urban morphology is combined with the results of thermal remote sensing analysis for Urban Heat Island (UHI) using Ecostress and the survey results of an integrated discrete choice experiment for NBS. This study delineated the geographically vulnerable areas and how the most vulnerable people perceive their affectedness. In both Budapest and Vienna, heat is felt more intensely and impacts health to a greater extent in low-income neighborhoods with limited access to and poor-quality green areas. However, residents of Budapest stated to have more experience with heat waves and respondents indicated much higher rates of heat negatively affecting them. Budapest reports higher UHI intensity than Vienna - meaning that the difference between perceived heat and actual temperatures is higher in Vienna. Budapest 18th district has been deploying NBS to address extreme heat and flooding. The learnings from the deployment in Budapest and the choice experiment results in terms of preference of NBS feed into suggesting optimum NBS solutions for Vienna.

Dense and urbanized European capitals under the Austro-Hungarian empire were developed at the end of the 19th century. In both Vienna (Austria) and Budapest (Hungary), the historic city defense structures were developed into dense, prestigious housing areas with at least four stories. While important cultural heritage, many historically built-up areas are now a challenge for heat reduction and urban planning. In Central Europe, nature-based solutions are being eyed as measures to tackle urban heat islands and the unequal distribution of green areas across cities. In Vienna and Budapest, the local populations are facing growing climate change impacts in the form of heatwaves and tropical nights, which are expected to negatively affect health and wellbeing. Combining the results of urban heat modelling with the results of a survey with an integrated discrete choice experiment conducted in Budapest and Vienna, this study investigated which geographical parts of the cities are more affected than others, which citizens are the most vulnerable and how they perceive their own affectedness. By combining data on actual and perceived impacts of the temperature, urban areas are identified which are in greater need of nature-based solutions. By identifying the residents of these areas, vulnerable social groups requiring city administration’s attention and support are identified and policy recommendations are given. In both Budapest and Vienna heat is felt more intensely and impacts health to a greater extent in neighborhoods with limited access to and poor-quality green areas, while neighborhoods with ample access to public and private green areas are not as strongly impacted by high temperatures. However, residents of Budapest stated to have more experience with heat waves and respondents indicated much higher rates of heat negatively effecting both their wellbeing and their health. This feeling was not confirmed by the heat models – meaning that the difference between perceived heat and actual temperatures is higher in Budapest. For urban planners the results of this study translate into setting clear planning priorities and goals specific to their residents’ needs: To gain the greatest possible benefits for residents and reduce urban heat island effects, nature-based solutions targeting heat reduction should be placed in neighborhoods which demonstrate high heat perception based on social analysis and heat modeling. By using this approach, planners will address both climate change and its impacts on the population in urban environments.