This finding was recently presented in Journal of Glaciology by Tron Laumann and Atle Nesje. The researchers used a flow-line model, coupled with a surface mass-balance model forced by climate data from Bergen, to simulate future frontal changes of Briksdalsbreen under various future climate scenarios. Briksdalsbreen is a western outlet glacier from Jostedalsbreen in western Norway
Frontal time lag and response time
The model was used to calculate the time lag of frontal response to a sudden and short change in the mass-balance. According to the model, the front has a time lag for maximum advance rate of 4-5 years, in close agreement with previous studies. The response time for Briksdalsbreen was calculated by running the model for 200 years with different mass-balance perturbations. For mass-balance perturbations of +0.30 m and +0.6 m water equivalents, the model yields response times of 52 and 60 years, respectively.
Future frontal retreat
The researchers ran the model from 1963 to 2007 with measured mass-balance data, and from 2007 to 2085 using calculated mass balances from 12 different climate scenarios. The model predicts frontal retreat up the steep valley from the lake inlet, with a total retreat of 2.5-5 km by 2085. A spectacular icefall, which today is one of the main tourist attractions in western Norway, may thus disappear and the glacier may become a plateau glacier that gradually will melt down.