Contemporary dynamics of glacial lakes: comparison between selected systems developing in northern, central and southern regions in Spitsbergen

Abstract

The study investigates glacial lakes in Svalbard, examining examples from the forelands of Gåsbreen, Crammerbreen, Knivseggbreen, Neppebreen and Ragnarbreen, each representing different classifications of glacial lakes, including ice-dammed, frontal moraine-dammed and medial moraine-dammed. These lakes serve as key indicators of ongoing climate change and the effects of deglaciation processes in polar landscapes. Quantitative analyses reveal notable differences among the selected glacial lakes. For instance, Goësvatnet experienced cyclical glacial lake outburst floods (GLOFs), with a recorded volume of 666,389 m3 during one event. Conversely, the lake on the Ragnarbreen foreland, while stable, has not encountered any GLOFs, indicating a distinct response to deglaciation compared with other examples. Hydrographic and surface analyses, conducted using digital elevation models (DEMs) and remote sensing data, provide insights into the morphological characteristics and dynamics of the glacial lakes and surrounding landscapes. Longitudinal profiles of glaciers show varied terrains, with Ragnarbreen exhibiting the least variability due to its source zone on the ice cap, while Crammerbreen presents diverse features, including tectonic faults resulting in icefalls with slopes >35°. By including multiple glacial lakes across different locations and classifications, this study offers a comprehensive understanding of the diverse responses of glacial lakes to deglaciation processes in Svalbard, shedding light on the complex interactions between glaciers, lakes and changing environmental conditions in the Arctic region.