There are a lot of glaciers on planet Earth – some estimate more than 100,000!  And since to measure the thickness of a glacier requires dragging instruments around on its surface, or flying over it in an aircraft, scientists and surveyors have only measured the thickness of a tiny fraction of them.  How then, are we to estimate how much ice is contained in glaciers in each mountain region, and how much sea-level rise could be generated if they were to melt?  Frank Paul and Andreas Linsbauer have an answer.  They have developed a method that used digital maps of glaciers, to extract just a few simple parameters to describe all the glaciers in a particular region.  Knowing the thickness of just a few of these glaciers allows them to calibrate a relationship between these simple parameters and the glacier volume.  Using a test site in the Bernina region of the Alps in Switzerland they’ve soon that the method works, and how much uncertainty remains.  The approach is, perhaps, not ideal, but for the present, this is definitely the best we can do, and it will allow Paul and his colleagues to provide ice2sea with a much better estimation of the volume of ice in various mountain regions; and more importantly, to quantify the remaining uncertainty.  Meanwhile, for those glaciologists still out there dragging those instruments around out on the glaciers – measure more, work harder!

Ice2sea Work Package:  WP3.3

Publication: (Paul and Linsbauer, 2009)