Ice volume distribution and implications on runoff projections in a glacierized catchment

摘要

A dense network of helicopter-based ground-penetrating radar (GPR)measurements was used to determine the ice-thickness distribution in theMauvoisin region. The comprehensive set of ice-thickness measurements wascombined with an ice-thickness estimation approach for an accuratedetermination of the bedrock. A total ice volume of 3.69 ± 0.31 km3and a maximum ice thickness of 290 m were found. The ice-thickness valueswere then employed as input for a combined glacio-hydrological model forcedby most recent regional climate scenarios. This model provided glacierevolution and runoff projections for the period 2010–2100. Runoffprojections of the measured initial ice volume distribution show an increasein annual runoff of 4% in the next two decades, followed by a persistentrunoff decrease until 2100. Finally, we checked the influence of theice-thickness distribution on runoff projections. Our analyses revealed thatreliable estimates of the ice volume are essential for modelling futureglacier and runoff evolution. Wrong estimations of the total ice volume mighteven lead to deviations of the predicted general runoff trend.