When it comes to measuring the challenges of the 'human dimensions' of climate change, it seems social scientists will be taking centre stage. That was a key opening message from the International Human Dimensions Programme on Global Environmental Change Open Meeting in Bonn, Germany, 26–30 April, reports Anna Barnett on the blog Climate Feedback (http://tinyurl.com/ceekvx).

Barnett, assistant editor of Nature Reports: Climate Change, caught up with one of the keynote speakers, physicist Hans Joachim Schellnhuber, at a coffee break. He told her that physicists can describe climate threats increasingly vividly, but that it's up to social scientists to figure out how we bring about massive economic and social transformation.

For example, the technical problems with transferring solar power from the Sahara to Europe are already solved. It's the lack of legal frameworks, intergovernmental agreements and international will that stands in the way, Schellnhuber said. He urged social scientists to take the lead and to rethink their research scales from the local case study to globe-spanning projects.