Jökull - 01.10.1998, Side 31

(Warrick and others, 1996). Recent worldwide compi-
lations of glacier mass balance (Dyurgerov and
Meier, 1997a,b) indicate that melting of small glaciers
on Earth (excluding the ice sheets of Greenland and
Antarctica) contributed 0.25 + 0.1 mm a_1 to global
sea level rise in the period 1961 to 1990.
GLACIER VARIATIONS IN ICELAND
SINCE 1930
Records of glacier variations in Iceland show a
clear relationship with climate and such records have
been used as an indicator of historical climatic varia-
tions, before regular weather monitoring was started
in Iceland around the middle of the nineteenth centu-
ry (Þórarinsson, 1974). Many glaciers in Iceland start-
ed retreating from their Little Ice Age maximum be-
tween 1850 and 1900 and the rate of retreat became
quite rapid after 1930. As the climate gradually
cooled after 1940, the retreat of the glaciers slowed
down and many glaciers started advancing after 1970
(Þórarinsson, 1974; Björnsson, 1979). After about
1985 the climate has become warmer and many
glaciers have started retreating again.
Figure 1 shows a photograph of the outlet glacier
Sólheimajökull, which flows to the south from the ice
cap Mýrdalsjökull, S-Iceland (Fig. 2), and Figure 3a
shows the advance and retreat of Sólheimajökull from
1930/31 to 1994/95. Figure 3a shows a rapid retreat of
Sólheimajökull between 1930 and 1960 followed by
an advance which has slowed down markedly in re-
cent years.
Sólheimajökull is a non-surging glacier which is
directly affected by climate changes (Sigurðsson and
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