Jökull - 01.01.2020, Side 24

Glacier extent in Iceland, 1890–2019
Figure 9: The extent of Snæfellsjökull ice cap at several times since the LIA maximum in ∼1890. – Útlínur Snæfellsjökuls
á mismunandi tímum frá því um 1890.
the average surface lowering was approximately 15 m
(Jóhannesson et al., 2011), and Snæfellsjökull is ex-
pected to lose proportionally more mass in the near
future than most other well-known Icelandic glaciers
(Jóhannesson et al., 2011), although it may not dis-
appear entirely since the bed reaches > 1400 m a.s.l.,
well above the local ELA (unpubl. data).
Þrándarjökull and Hofsjökull eystri
Þrándarjökull and Hofsjökull eystri have decreased
by 20 km2 and 9 km2, respectively, loosing approx-
imately 59% and 73% of their maximum LIA size
(Table 2). Their maximum LIA extent of was de-
lineated from remote sensing data and is based on
sparse glacial geomorphological landforms around
the glaciers (Figure 10). The outlines since the mid-
20th century have been mapped in more detail from
aerial images (Belart et al., 2020).
Glaciers on Tröllaskagi and Flateyjarskagi
The total area of glaciers on Tröllaskagi decreased
by 74 km2 during ∼1890–2019 (Table 2), which is
close to 40% of their cumulative maximum LIA area.
However, as mentioned previously, the maximum LIA
glacier outline has not been traced in detail except
for few glaciers on the peninsula. The maximum LIA
extent for most of the glaciers on Tröllaskagi penin-
sula has been derived from remote sensing data only;
only a few glaciers have been studied in detail (Casel-
dine, 1985; Caseldine and Stötter, 1993; Stötter et al.
1999; Wastl et al., 2001; Brynjólfsson et al., 2012;
Fernández-Fernández et al., 2017, 2019; Tanarro et
al., 2019). Reliable information about the age of the
LIA moraines comes mainly from radiocarbon dating
and tephrochronology (Häberle, 1991, 1994; Stötter,
1991; Stötter et al., 1999; Wastl and Stötter, 2005).
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