Already in my early years, I was fascinated by cold mountains with snow and ice. Today, my research and consulting focuses on impacts from global warming on glaciers and permafrost as related to natural hazards and environmental evolution through time.

I am professor emeritus at the Geography Department, University of Zurich, Switzerland.

I obtained my PhD on alpine permafrost in 1974 at the University of Basel and my habilitation in glaciology and geomorphology in 1985 at ETH Zurich, where I was head of the Glaciology Section at the Laboratory of Hydraulics, Hydrology and Glaciology from 1989 to 1995. From 1995 to 2013, I was full professor of Physical Geography at the University of Zurich, and from 1986 to 2010 director of the World Glacier Monitoring Service (WGMS).

From 1996 to 2009 I was involved with the integration of glaciers and permafrost as Essential Climate Variables into the terrestrial part of the Global Climate Observing System (GCOS) of the United Nations Environment Programme (UNEP) and the International Council of Science (ICSU).

Over many years, I have been actively involved in various functions with the IPCC assessment reports. Together with Colin Whiteman, I edited the book on „Snow and Ice-Related Hazards, Risks, and Desasters“, which was first published in 2015 and as a second updated edition in 2021.