1. College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Sino−French Institute for Earth System Science, Peking University, Beijing 100871, P. R. China
2. School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30318, United States
3. Key Laboratory of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, P. R. China
4. The Bartlett School of Construction and Project Management, University College London, London WC1E 7HB, United Kingdom