Climate Impact Diagrams

Figure 8: Example of an impact diagram Photo by CAS. 

Tool description

Climate impact diagrams aim to build a shared understanding among all city stakeholders on the opportunities and risks of climate change for the different city sectors. It is a first step to start the conversation about climate change adaptation and work towards a joint approach for taking climate measures, identifying co-benefits and offering ideas for action. Impact diagrams present a simplified, visual summary of current scientific knowledge of climate effects and climate consequences in a city. The diagrams help to gain more insight into opportunities and risks and can kickstart the search for additional knowledge or collaboration partners.


Would you like to know which tools are complementary? Click here.

The impact diagrams workshop can be organised by cities on their own, but for a more thorough approach, it is necessary to bring climate science expertise to the workshop (e.g., from the national meteorological service).

Benefits of using the tool

The impact diagrams are a decision support tool that are appealing for policymakers. They visualise possible outcomes for those making climate investment decisions and enhance dialogue between science and policy.

They offer a visual summary of the climate change impacts by sector (economic, social and natural) in order to contribute to the development of adaptation plans.

Impact diagrams can help cities and city staff to gain insight into the opportunities and risks of climate change for their own field of work, and can enable focussed discussion between stakeholders about adaptation options and priorities.

Triple-A phases

The tool can be used in the following Triple-A phases:

Analysis phase:

• Identifying sector-based climate impacts for a city.
• Prioritising climate impacts.
• Assessing the key climate risks for a city.


For a practical guide on how to develop impact diagrams and organize a workshop, please refer to the Climate impact diagrams & risk workshop guide.


Climate Adaptation Services (CAS)

Felix van Veldhoven
Sophie van der Horst
Timo Kelder


More information at

The tool begins with a city specific analysis of climate trends, based on models and observations. All REACHOUT tools that are able to describe such trends work well with the development of climate impact diagrams. These include for example the Thermal Assessment Tool (Tecnalia), Community Flood Resilience Support System (Deltares) and Pluvial flood hazard and risk assessment (CMCC).

The climate story of Gdynia​

Short summary: A story about Jan and Maria during extreme precipitation.

Theme: Flooding

End user: Citizens

Link to the story: under construction