Jökull - 01.01.2020, Blaðsíða 84

Little Ice Age advance of Kvískerjajöklar, Öræfajökull, Iceland.
Figure 7. Surface elevation changes from LIAmax to 1930 and 2011 of a) South glacier and b) North glacier. –
Snið af yfirborðsbreytingum (3. mynd) frá hámarksstöðu á litlu ísöld til 2011, a) nyrðri og b) syðri jökulinn.
Table 1. Changes of Kvískerjajöklar since the LIAmax. Period, number of years, area changes (A) and area
loss (∆A) in km2. Volume loss (∆V) as water equivalent (w.e.), annual average volume loss (AAVL) and
annual average specific mass balance in w.e. – Flatar- og rúmmálsbreytingar frá hámarki litlu ísaldar. Tímabil
og fjöldi ára, flatarmálsbreyting (A) og flatarmálstap (∆A) á umræddum tímabilum, rúmmálsrýrnun (∆V) í
vatnsgildi (w.e.), árleg meðaltalsrýrnun (AAVL) og afkoma.
A ∆A ∆V AAVL m a−1
Period Years (km2) (km2) (w.e. km3) (ice km3 a−1) (w.e.)
LIAmax*–1880 130 10.5–10.1 0.4 0.02±0.1 0.003 -0.01
1880–1930 50 10.1–9.5 0.6 0.13±0.1 0.012 -0.27
1930–2011 81 9.5–6.4 3.1 0.3±0.08 0.039 -0.47
1750–2011 261 10.5–6.4 4.1 0.45±0.1 0.016 -0.2
1880–2011 131 10.1–6.4 3.7 0.43±0.1 0.029 -0.4
∗Here assumed to be in 1750s, with an area of 10.5 km2.
ent elevation ranges to the total volume changes are
combined as root mean square).
CONCLUDING REMARKS
Kvískerjajöklar are among the smallest outlet glaciers
draining the Öræfajökull ice cap and respond swiftly
to climate variations. These outlets reached their max-
imum extent in the 18th century and remained at an
advanced position throughout the 19th century, pro-
ducing a series of moraines indicating a number of
readvances before they eventually started retreating
during the relatively warmer 20th century. Both out-
lets gradually receded during the 20th century until
the 1980s when their snouts started to oscillate for
two decades: the North glacier terminus at elevations
500–600 m a.s.l. and that of the South outlet at 600–
680 m a.s.l. In this period, the North glacier advanced
> 300 m beyond its position in 1945 and to a point
JÖKULL No. 70, 2020 81