Report describing strategy on communicating level of confidence

Work Package 33 of the EUPORIAS project has been undertaken to identify good practice in the communication of confidence and uncertainty in climate predictions. In this report we draw on the findings of a user needs survey, online decision lab, and the ongoing work taking place in four of the EUPORIAS prototypes to make the following recommendations:

  • Tailor (where possible)
    Even within the same sector users of climate information can vary considerably in expertise, information requirements, and preferences for receiving information about confidence and uncertainty. Tailored communications produced in collaboration with specific stakeholders are likely to be the most useful and best understood formats of communication.
  • Layer information
    When it is not possible to provide highly tailored communications, a tiered provision of information may help to address the needs of users differing in information requirements. Here, documents and tools may be layered so that users can easily access either a simple overview or more detailed and complex information about the forecast.
  • Provide a framework for understanding forecast performance
    Measures of ‘skill’ represent the extent to which forecasts perform better or worse than historical data (‘climatology’) when it comes to predicting future conditions. However, even for users with statistical expertise raw skill scores can be difficult use without guidance as to “what they mean”. It is therefore recommended that providers give users a framework for understanding skill. This may take the form of labelled categories (e.g. No skill, Low skill, Medium skill, High skill), visual cues (e.g. colour or opacity), or simple numeric categories (e.g. a score of 1-4 on a “performance index”)
  • Test communications
    When developing strategies for communicating confidence and uncertainty it is not always immediately obvious where misinterpretations and usability issues may arise. It is vital that communications be tested with their intended users, and if necessary revised, to ensure that they are both usable and well understood.