CIRCLE 2 policy brief: Communicate uncertainties- design climate adaptation measures to be flexible and robust

This policy brief is directed towards funders and managers of climate change impacts and adaptation research programmes as well as policy makers in this area. It notes various challenges in addressing uncertainties in climate change research and policy and provides suggestions on how to address them. Projections of future climate change and associated impacts are riddled with uncertainties – a great challenge at all levels of policy- and decision-making. There is uncertainty about observed climate changes and its past effects on natural and human systems. There is uncertainty about the current state of the environment and its resilience to changes. And there is even larger uncertainty about future changes in the climate system and their potential consequences for the environment and human societies. Planning for climate change adaptation (e.g. developing political strategies or deciding on the implementation of adaptation measures) is a relatively new challenge for national and local decision makers. Planners and managers across sectors have to take decisions now about future strategies, measures and investments that are expected to protect their systems against potential climate vulnerabilities. This means taking into consideration an immense and yet growing amount knowledge and data about climate change projections, socio-economic scenarios, and methods for assessing impacts and vulnerabilities. In order to account for national and local decision makers’ perspectives and support better informed decisions, knowledge about the climate system and impacts has to be communicated in a clear and meaningful way taking proper account of associated uncertainties. New focused research is required to advance the knowledge and understanding of how to present uncertainty so that it can inform policy and decision makers most effectively. At the same time, training should be provided to the current and next generation of researchers to communicate effectively on these complex issues. Policy makers should be supported to appreciate and interpret the uncertainty information that science is providing