1. Norwegian Polar Institute, N-9005 Trorns, Norway;
2. SINTEF Civil and Environmental Engineering, N-7034 Trurrdheinr, Norway;
3. The University Courses on Svalbard, P.O. Bo.r 156, N-9170 Longyearbyen, Norway;
4. Department of Hydraulic and Environmental Engineering, Norwegian University of Science and Technology, N-7034 Trotidheim, Norway