Sensitivity of Folgefonna ice cap to anthropogenic climate change

Glaciers in Norway are retreating, following the global trend caused by climate change. Future mass loss is projected to increase and cause the majority of Norwegian glaciers to disappear by the end of the century. This alters runoff and downstream hydrology, thus affecting available water resources for local communities. Quantifying this future change is essential to aid societal climate adaptation.

In this work, our aim is to assess both the rate of change and how trustworthy these estimates are given uncertainty in future climate and simulation tools. We organize the study around the Folgefonna ice cap in Western Norway, a prime example of a maritime ice cap. For the people living in its vicinity, the ice cap is important as it acts as a reservoir for both hydropower generation and drinking water. Despite this, little is known about how it will change in the future.

Using the model BESSI (The Bergen Snow Simulator), we simulate the surface mass balance of Folgefonna at a high spatial resolution. Recent developments of BESSI have made it a suitable option for small-scale glacier studies. These model alterations are presented here as well as results of past and future surface mass balance for the ice cap. We quantify how sensitive Folgefonna is to climate change and discuss limitations to the tools available for future glacier projections.