The role of dead ice in transforming glacier forelands under the rapid climate warming of recent decades, OscarIILand, Svalbard

Abstract

The rapid climate changes of recent decades are causing rapid glacier recession in the high Arctic and the loss of large patches and blocks of dead ice. Their temporally differentiated melting is very significantly transforming the relief of marginal zones, creating dead‐ice landscapes. The article focuses on dead‐ice degradation processes in the forelands of two glaciers (Erikkabreen and Haakenbreen) on Oscar II Land in Spitsbergen. Detailed in‐field geomorphological mappings have been conducted twice (in 1989 and 2022) in the two glaciers' forelands. These were combined with analysis of available photogrammetry and Digital Elevation Models, allowing the authors to describe the dynamics of dead‐ice melting processes within various landforms and the effect of those processes on the forms' ultimate morphology. This provided a broad view of the trajectory of melt processes depending on local geomorphological and hydrological conditions. Particular attention was paid to the interactions between the evolution of permafrost and the course of melting of dead ice. In light of the highly dynamic thermokarst processes in the forelands of Svalbard glaciers, the term ‘dead‐ice‐rich permafrost’ is proposed. It was found that global climate changes are increasing the role of dead ice in transforming the relief of glacier forelands, thereby increasing the occurrence of dead‐ice landscapes. The conclusions confirmed those for other contemporary glaciation areas and may significantly help in interpreting the morphogenesis of glacial relief formed during past continental glaciations.