Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 2
items per page: 25 50 75
Sort by:

Abstract

The results of a statistical analysis of the influence of the Hansbreen surface ablation relative to selectedmeteorological parameters (air temperature andsunshine duration) are presentedhere. Over the period1989 –2001 the lowest summer balance on the surface ablation of Hansbreen was recorded in 1994 (–0.56 m water equivalent). Concurrently, both the air temperature (mean seasonal ~2.3 °C) and the sunshine duration (seasonal sum ~278.9 h)were at their lowest. Owing to the relatively high sunshine duration (676.5 h),the highest values were in 1998 (–1.71 m w.e.); likewise,in 2001 (–1.84 m w.e.) when a high air temperature (mean of 3.6 °C) occurred. The statistical models erected on the basis of these data allow us to estimate fairly reliably the seasonal ablation of Hansbreen. The basis of these is the reasonably reliable relationship determinable between the seasonal sum of PDD (positive degree days) and the ablation intensity changes in respect of altitude above sea level. Sunshine duration is regarded here as being of very little significance in terms of increasing the accuracy of the models. The errors inherent in this models varies from 28% to as little as 7%. Shown models may eventually find application as a method of calculating the amount of water resulting from the decay of tidewater glaciers.
Go to article

Abstract

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.
Go to article

This page uses 'cookies'. Learn more