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Recent transformations in the high-Arctic glacier landsystem, Ragnarbreen, Svalbard

Glacial and paraglacial environments

Auteur(s) et Affiliation(s)

Fac. of Geographical and Geological Sciences, Adam Mickiewicz Univ., Poznań, Pologne
Dept. of Geography , Univ., Durham, Royaume-Uni
KNIGHT, J.
School of Geography, Archaeology and Environmental Studies, Univ. of Witwatersrand, Johannesburg, Afrique du Sud
HARRISON, S.
College of Life and Environmental Sciences, Univ., Exeter, Royaume-Uni


Description :
Ragnarbreen is a small glacier located in the central part of Spitsbergen Island. Glacier recession and landforms' development in the foreland of Ragnarbreen are quantified using time-series orthophotos and digital elevation models, which were generated based on aerial photographs from 1961 (black and white frame camera), 1990 (false infrared frame camera) and 2009 (colour digital camera), obtained from the Norsk Polar Institute. Receding from its maximum Little Ice Age extent, attained in the period 1900/1920-2013, the glacier margin retreated by 1658 m while the extent of the area of ice decreased by 26%. In terms of landscape alteration between 1961 and 2009, the most important was the creation of a terminoglacial lake, which acted as a sedimentary trap and at the same time probably accelerated glacier retreat. The second most active component was the lateral moraines whose transformations were divided into 4 phases, with various magnitudes of debris flow and backwasting activity that changed with time. The end moraine complex was the most stable component, affected mainly by dead-ice downwasting and to a lesser extent by sporadic debris flows.


Type de document :
Article de monographie

Source :
Geografiska annaler. Series A. Physical geography, issn : 0435-3676, 2014, vol. 96, n°. 3, p. 265-285, nombre de pages : 21, Références bibliographiques : 52 ref.

Date :
2014

Editeur :
Pays édition : Suede, Stockholm, Svenska sällskapet för antropologi och geografi

Langue :
Anglais
Droits :
Tous droits réservés © Prodig - Bibliographie Géographique Internationale (BGI)