Strategies for adaptation to and mitigation of climate change: Key performance indicators to assess nature-based solutions performances

Climate change is affecting both natural and urban environments with serious consequences on their balance and ecosystems. The introduction of nature-based solutions (NBS) in cities can help to manage its effects, both in terms of mitigation and adaptation and in parallel, it can also support ecosystem service provision. In order to quantify the performances of NBS in terms of benefits for humans and climate change effect reduction, Key Performance Indicators (KPIs) can be used. This paper presents a literature review focused on the identification of KPIs for climate change adaptation and mitigation measures and on the possible role of NBS in this context. More in detail, the main steps of the review are the following: identification of the most common climate change drivers and relative effects, definition of a set of KPIs to measure performance in relation to the specific effects of climate change, identification of the relative Sustainable Development Goals (SDGs) and Ecosystem Services (ES), and finally, identification of possible NBS for adaptation to and/or mitigation of climate change. The results highlight the potentiality of NBS both at the building and at the district and urban scale in managing the challenges posed by climate change, in particular in terms of adaptation. Furthermore, the review shows that KPIs are widely used in environmental assessment tools, and they can be a useful tool to measure NBS performances.