Multidecadal analysis of paraglacial landscape changes in the foreland
of Gåsbreen - Sørkapp Land, Svalbard
Abstract
The change in the structure of the polar landscape since the termination
of the Little Ice Age (ca. 1900) is expressed by widespread retreat of
glaciers, progressive exposure of glacial landforms at ice margins and
opening ice marginal zones to increasing paraglacial and periglacial
processes operating synchronously in adjacent areas. This study provides
insights into the rate of post-LIA deglaciation and associated
paraglacial transformation in foreland of Gåsbreen, a glacier situated
in north-western Sørkapp Land, region characterized by one of fastest
deglaciation rates in the entire Svalbard Archipelago. During the
investigated period, 1938-2020, Gåsbreen was in a recession that
accelerated after 1990 and as a result the area of its marginal zone
almost tripled from 2.2 km² to 5.8 km². This process had a significant
impact on the development of the relief in glacier foreland. The
dynamics of landscape transformation in the glacier marginal zone
manifested in degradation in the surface of ice-cored moraines and the
forms that are underlain by dead-ice. Mass movements and debris flow on
ice-cored moraines and fluvioglacial processes had a great influence on
this transformation. Larger volume of proglacial waters intensified
denudation, transport and accumulation of sediments, which resulted, in:
an increase in the surface of sandurs and proglacial riverbeds, an
increase in the area of lakes, extending and changing of the course of
rivers in marginal zone.