Co-design is a core component of how climate information becomes actionable. The C3S Climate Hazard Screening and Exploration Tool is a climate service for the financial sector. The tool will enable users to screen multiple climate hazards across project locations and identify where a robust climate change signal flags the need for climate adaptation planning or further climate risk assessment.
The design challenge was translating rigorous and complex climate science –including model uncertainty– into a format that supports decision-making in fast-paced professional environments where time and cognitive bandwidth are limited.
Through an iterative co-design process with end users, we demonstrate how UX and information design support clarity without oversimplifying scientific nuances.
Key design principles results include:
1. progressive discovery, allowing users to access only the minimum information required for rapid decisions while enabling deeper exploration when needed;
2. clear information hierarchy that enhances information scannability through layout, size, typography, and colour;
3. intentional iconographic choices for the flagging system, recognising that symbols such as warnings, flags, or prohibition marks can carry different meanings across professional communities;
4. curated semantics of colour, given the strong cultural associations attached to colours such as red, orange, and yellow in signalling urgency, risk, or caution.
The work shows that effective climate service design requires more than scientifically robust data visualisation. It also requires meaningful stakeholder engagement, testing, and simplification of visual encoding to enable confident and fast decision-making while preserving access to the underlying scientific depth and complexity.