The influence of the fluctuations of the surge type outlets, constituting most of W-Vatnajökull area and a good part of N-

• Main Authors: Helgi Björnsson A, Jørgen Dall B, Finnur Pálsson A
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2005
• Subjects: glacier changes; SAR; PolSAR; terminal morainesThe 20th century retreat of ice caps in Iceland derived from airborne SAR; W-Vatnajökull and N-Mýrdalsjökull; glacier; Iceland
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.591.1030; http://www.raunvis.hi.is/~eyjolfm/EPL_em_et_al.pdf

(F. Pálsson).Mýrdalsjökull area, is minimal, since they had all recently surged in 1998 as was presumably the case when the outermost moraines were formed. The major contributor to the area decrease is therefore climate changes in the 20th century even though the glacier retreat has been interrupted by short-lived surges. Moraines associated with most of the surges in W-Vatnajökull in the 20th century are observed in the SAR data including the most recent surges in the 1990s. Interestingly no push moraines were observed in front of the surge advance, but the moraines appear when the glaciers start retreating. We estimate that the collective decrease of the outlets of western Vatnajökull since maximum Neoglacial extent of each outlet, is 109 km2 (6.7%) corresponding to an average retreat of 850 m over a 130 km long margin. In the same period the outlet Sléttjökull, in N-Mýrdalsjökull, has decreased by 33 km2 (20%) corresponding to an average retreat of 1500 m over a 20 km long margin.