On the expression and distribution of glacial trimlines: a case study of Little Ice Age trimlines on Svalbard

Abstract

Glacial trimlines are important features for constraining 3-dimensional palaeoglaciological reconstructions, but relatively little is known about the processes of their formation and preservation. A new classification scheme for the expression of glacial trimlines was presented by Rootes and Clark (2020), with the aim to encourage further research into the processes of formation and preservation for trimlines. Here we present the first application of the trimline classification scheme to a case study location in central western Spitsbergen, Svalbard. Little Ice Age trimlines were mapped using remotely sensed imagery and the classification scheme applied. These data are presented and used to examine the factors that may influence the distribution and expression of trimlines in order to explore controls on their formation and preservation. Preliminary analysis suggests that the type of glacier, and geology, particularly the bedrock erodibility, may have an influence over the location and expression of glacial trimlines in Svalbard. These findings open the potential for trimlines to be used as part of diagnostic landsystems for specific types of glacier, such as marine-terminating tidewater glaciers, terrestrial glaciers or surge-type glaciers, and indicates that further research into glacial trimlines may enable these landforms to yield additional information about palaeo-ice masses than has previously been the case.