1. David and Lucile Packard Foundation, Los Altos, CA 94022, USA.
2. International Council for Science (ICSU), 75116 Paris, France.
3. International Social Science Council (ISSC), 75732 Paris, France.
4. National Research Foundation of South Africa, Pretoria, 0001, South Africa.
5. Indiana University, Bloomington, IN 47408, USA.
6. Stockholm Environment Institute, SE-106 91 Stockholm, Sweden.
7. Potsdam Institute for Climate Impact Research, 14473 Potsdam, Germany.
8. Environment and Natural Resources, International Development Research Centre, Ottawa K1G 3H9, Canada.