Accelerating retreat and high-elevation thinning of glaciers in central Spitsbergen

Jakub Małecki

doi:10.5194/tc-10-1317-2016

Abstract

Abstract. Svalbard is a heavily glacier-covered archipelago in the Arctic. Dickson Land (DL), in the central part of the largest island, Spitsbergen, is relatively arid and, as a result, glaciers there are relatively small and restricted mostly to valleys and cirques. This study presents a comprehensive analysis of glacier changes in DL based on inventories compiled from topographic maps and digital elevation models for the Little Ice Age (LIA) maximum, the 1960s, 1990, and 2009/2011. Total glacier area has decreased by ∼ 38 % since the LIA maximum, and front retreat increased over the study period. Recently, most of the local glaciers have been consistently thinning in all elevation bands, in contrast to larger Svalbard ice masses which remain closer to balance. The mean 1990–2009/2011 geodetic mass balance of glaciers in DL is among the most negative from the Svalbard regional means known from the literature.

Highlights

Small glaciers are natural indicators of climate, as they record even slight oscillations via changes of their thickness, length, and area (Oerlemans, 2005)
This paper presents an inventory of the ice masses in Dickson Land (DL) and quantifies changes of their geometry since Little Ice Age (LIA) termination
In the most recent 2009/2011 inventory 152 ice masses were catalogued in DL, all terminating on land and covering a total of 207.4 ± 4.6 km2 (14 % of the region). 110 ice masses (72 % of the population) have areas < 1 km2 and 86 of these are smaller than 0.5 km2

Summary

Introduction

Small glaciers are natural indicators of climate, as they record even slight oscillations via changes of their thickness, length, and area (Oerlemans, 2005). Twentieth century climate warming caused a volume loss of ice masses on a global scale (IPCC, 2013), contributing to about half of the recent rates of sea-level rise. The climate record suggests a sharp air temperature increase on Svalbard in the early 20th century, terminating the Little Ice Age (LIA) period around the 1920s (Hagen et al, 2003). Climate warming led to volume loss of the Svalbard glaciers ( with large spatial variability), after 1990 (Hagen et al, 2003; Kohler et al, 2007; Sobota, 2007; Nuth et al, 2007, 2010, 2013; Moholdt et al, 2010; James et al, 2012)

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Conclusion