Acceleration of deglaciation rate; Arctic; GIS; Recession rate; Svalbard
Polish Polar Research, Vol. 39, iss. 1 (2018), s. 77-98
This paper reports on a morphometric analysis of land-terminating glaciers on southern and western Spitsbergen in the years 1936–2014. An attempt was made to estimate the deglaciation rate and the scale of its acceleration in the 21st century in the conditions of Arctic amplification. Satellite scenes and topographic map sheets were used for the study and were analyzed by means of remote sensing and GIS methods. The study covered 2000–2014 years and concluded that surface recession accelerated on average by a factor of 2.75 compared to the 1936–2000 period, while linear recession was 2.2 times faster. The greatest increase in the deglaciation rate can be observed in the case of glaciers faced to N and W sectors. The deglaciation process is the most advanced in the central part of the island, where small, compact mountain glaciers predominate. In recent years, a slowdown in the deglaciation processes in these glaciers was observed. The studies demonstrate that the deglaciation rate was mainly influenced by the basin relief determining the glacier geometry. The resultant fractal nature of the ice cover makes it highly vulnerable to the disintegration of complex glacial systems into smaller ones due to glacier thinning and the separation of outlets. The acceleration of the deglaciation rate in turn is modified by the climate factor, especially the impact of warming air masses from the N and W sectors where seas are becoming increasingly ice-free and, consequently, have an increasing heat capacity.