Speaking: Bethan Davies, Newcastle University
Landscapes Live is a weekly online seminar series freely accessible to the international scientific community interested in various aspects of geomorphology.
Abstract
Large icefields and ice caps in high latitude regions are currently contributing significantly to global sea level rise, with Alaska leading contributions from glaciers. This contribution is likely to accelerate since icefield topography drives a non-linear response to climate change. Here we show that icefield area and volume loss from Juneau Icefield has accelerated exponentially over the last few decades, with catastrophic losses reaching -5.91 ± 0.80 km3 a-1 from 2010-2020. Thinning is now pervasive across the icefield plateau, resulting in glacier fragmentation, especially rapidly after 2005. This glaciological threshold response to a warming climate is underlain by the plateau hypsometry. The non-linear behavior is concerning for the future viability of this icefield and for plateau icefields and ice caps globally, with implications for future projections of sea-level contributions.