Jökull - 01.01.2012, Side 101

Post-Little Ice Age volume loss of the Kotárjökull glacier,
Figure 2. Oblique arieal photograph of Öræfajökull and Kotárjökull. The maximum LIA glacier extent is
marked with a dotted line. Traces of the terminus in Kotárgil are obscure, especially east of Slaga, hence two
possible extensions are presented. Photo. SG 17th of August 2006. – Flugmynd af Kotárjökli og Rótarfjalls-
jökli, tekin 17. ágúst 2006 (SG). Punktalínur marka útbreiðslu jökulsins við hámark litlu ísaldar. Ummerki um
stöðu sporðsins eru óljós neðst í Kotárgili og því eru tveir möguleikar sýndir.
imated from the surface slope of the glacier (Magn-
ússon et al., 2012). The glacier plateau receives the
highest amounts of annual precipitation in Iceland,
5700–7800 mm w.e., almost entirely falling as snow
(Björnsson et al., 1998; Guðmundsson, 2000). Com-
parison with observed precipitation from the nearest
lowland meteorological station Kvísker (Figure 1),
implies that the precipitation on the ice cap, is twice
as high as on the lowlands to the southeast of Öræfa-
jökull (Guðmundsson, 2000).
Kotárjökull covers at present about 11.5 km2, with
an average slope of 20◦, and the equilibrium line lies
around 1100–1200 m. Heading from an elevation of
1800 m, inside the caldera, the glacier is split into two
branches by Rótarfjall mountain (946 m): the main
branch terminating in 300–400 m wide gorge (Fig-
ures 1 and 2), and the eastern branch, Rótarfjallsjök-
ull. These glaciers surrounded Rótarfjall, and merged
together in Kotárgil, at the end of the 19th century
(Thoroddsen, 1896). Parts of the terminal moraine
northwest of Slaga mountain are obscure and may be
remnants of an older stage. No dead ice is observed
in the glacier’s marginal area.
JÖKULL No. 62, 2012 99