Jökull - 01.01.2019, Blaðsíða 16

Terminus lakes on the south side of Vatnajökull
Figure 11. The development of terminus lakes by Virkisjökull/Falljökull. For explanations and credits see
Figures 3 and 7. – Þróun sporðlóna við Virkisjökul/Falljökul (sjá nánari skýringar við 3. mynd og 7. mynd).
terminus in 1944 (F. Björnsson, 1956; AMS 1951;
NLSI, aerial images 1964). Four small lakes can be
seen by the terminus in 1964 as well as a small lake,
a little less than ∼0.01 km2, by the lateral ice margin
at Staðarfjall (NLSI, aerial images 1964), (Figure 13).
The maximum depth of the southernmost lake in 1963
was at least 37 m (Eyþórsson, 1963).
The glacier advanced over two of the lakes in 1981
(NLSI, aerial images 1980, 1981) and the area of the
lakes was further reduced by the advancing glacier
and accumulation of sediments in the 1980s and 1990s
(Figure 13).
The glacier has retreated substantially since 2000
and lakes have formed in dead ice left by the advances
of the 1980s (NLSI, aerial images 1964, 1980, 1981,
1992, 1998; Landsat 5, 2000, 2003; ASTER, 2001).
There were two lakes in 2006 that merged in 2010.
They separated again after a short-lived advance of
the glacier tongue in 2013 and 2014 but remerged in
2015. The lakes in front of Kvíárjökull grew from
∼0.02 km2 in 2001 to ∼0.65 km2 in 2018 (Figure 16).
Further retreat of Kvíárjökull may lead to the forma-
tion of a ∼4 km2 lake in a subglacial trough between
the impressive lateral moraines of this outlet glacier
(Magnússon and others, 2012).
Hrútárjökull
A lake located in Ærfjall by Hrútárjökull (Figure 14)
was a source of jökulhlaups until the middle of the
20th century. It may have reached an area > 0.1 km2
at its largest. This lake was present around 1880 but it
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