1. Department of Computational and Data Sciences, George Mason University, Fairfax, VA 22030, USA
2. Tellus Institute, Quincy, MA 02171, USA
3. Environmental Systems Analysis Group, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands
4. Munk School of Global Affairs and Public Policy, University of Toronto, Toronto, ON M52 3K7, Canada
5. Independent Researcher, 1210 Vienna, Austria
6. Korbel School of International Studies, University of Denver, Denver, CO 80208, USA
7. Department of Geography and the Environment, University of Denver, Denver, CO 80208, USA