1. Faculty of Civil and Environmental Engineering, School of Engineering and Natural Sciences, University of Iceland, 107 Reykjavík, Iceland
2. Department of Geography, Faculty of Mathematics and Natural Sciences, University of Bonn, 53115 Bonn, Germany
3. Department of Economics, Faculty of Law and Economics, University of Bonn, 53113 Bonn, Germany
4. Environment and Natural Resources, School of Engineering and Natural Sciences, University of Iceland, 107 Reykjavík, Iceland