Environment Vol. 47, Issue 8, Pages 10-25 October 2005 HKS Authors See citation below for complete author information. William Clark Harvey Brooks Research Professor of International Science, Public Policy and Human Development Citation Schellnhuber, Hans Joachim, Paul J. Crutzen, William C. Clark, and Julian Hunt. "Earth Systems Analysis for Sustainability." Environment 47.8 (October 2005): 10-25.