Ross A Woods, University of Bristol, Bristol, BS8, United Kingdom, Joshua R. Larsen, University of Birmingham, School of Geography, Earth and Environmental Sciences, Birmingham, United Kingdom, Bettina Schaefli, Institute of Earth Surface Dynamics, Faculty of Geosciences and Environment, University of Lausanne, Lausanne, Switzerland and Natalie C Ceperley, EPFL ENAC EFLUM, Lausanne, Switzerland