1. Research Associate, CRYOS, Laboratory of Cryospheric Sciences, Institute of Environmental Engineering, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Station 2, CH-1015 Lausanne, Switzerland (corresponding author).
2. Professor and Chair of Environmental Engineering, Institute for Infrastructure and Environment, School of Engineering, Univ. of Edinburgh, Edinburgh EH8 9YL, U.K.