Jökull - 01.06.2000, Page 17

Ice-thickness measurements on Sólheimajökull
CONCLUSIONS
1. Sólheimajökull was found to occupy an over-
deepened parabolic trough, ranging from one to two
kilometres in width and reaching a maximum depth
of 430 m. The glacier was thicker and had a grea-
ter extent in 1996 than as shown on the DMA map.
This reflects the glacial advance of 482 m that occur-
red between 1970 and 1995.
2. Sólheimajökull has the characteristics of an acti-
ve glacier that flows regularly, is very sensitive to
climatic change, and responds quickly. The current
advance is likely to reflect recent changes in mass bal-
ance. No evidence of surge-type behaviour could be
found.
ACKNOWLEDGEMENTS
We thank the National Geographic Society, the Car-
negie Trust for Universities of Scotland and the
NABO programme (National Science Foundation
of America) who supported various aspects of this
project. Dan Millington and Ágúst Bjartmarsson
of Björgunarsveitin Víkverji provided field assist-
ance. Andrew Mackintosh is grateful for the supp-
ort of an ORS Award and a University of Edinburgh
Geography Department Studentship. We also thank
the two anonymous referees whose valuable comm-
ents improved the manuscript.
ÁGRIP
ÍSSJÁRMÆLINGAR Á SÓLHEIMAJÖKLI
Issjármælingar með punktíssjá sýna að Sólheimajök-
ull er allt að 433 m þykkur og liggur í 10 km löngum,
U-laga dal sem nær niður undir sjávarmál á u.þ.b. 3,5
km kafla innan við núverandi jökulsporð. Þarna hef-
ur því sennilegast verið fjörður við hærri sjávarstöðu
snemma á nútíma (Holocene). Jökullinn er um 200 m
þykkur við jaðar Kötluöskjunnar en að meðaltali um
tvöfalt þykkari neðan hennar. Lögun jökulsins gefur
til kynna að hann sé næmur fyrir veðurfarsbreyting-
um. Framskriðið á árunum 1970-1995 stafar líkleg-
ast frá aukinni ákomu ofarlega á jöklinum undanfarna
áratugi.
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