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Nr. 4, Review of Survey activities 2003, pp. 85-88


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85
Jakobshavn Isbræ (also known as Sermeq Kujalleq or Ilulissat
Isbræ) is situated at about 69°10
N and 50°00W in West
Greenland. This major outlet from the Inland Ice has an
extremely high rate of movement (nearly 1 m/hour) and thus
a high production of icebergs, which via the icefjord float
westwards through Disko Bugt to Davis Strait (Fig. 1).
Estimates of the iceberg production are in the range of 35
10 km
3
ice per year, more than 10% of the entire calf-ice pro-
duction of the Inland Ice (e.g. Bauer l968; Bindschadler
1984). The icefjord into which Sermeq Kujalleq calves is
Kangia, best known in glaciological literature as Jakobshavn
Isfjord. Spectacular changes of the glacier were observed dur-
ing 2002 and 2003 at the same time as it was nominated for
inclusion in the UNESCO World Heritage List under the
name `Ilulissat Icefjord'.
Nomination of 'Ilulissat Icefjord' and
Sermeq Kujalleq
The Eskimo ruins and archaeological sites in the region
around the modern Greenland township of Ilulissat include
representatives of all the cultural phases since the first Eskimo
settlement of Greenland. The association with Greenland's
most productive glacier makes the `Ilulissat Icefjord' area a
strong candidate for inclusion in the UNESCO World
Heritage List. In December 2000 the Government of
Greenland decided to nominate `Ilulissat Icefjord', and the
Geological Survey of Denmark and Greenland (GEUS) was
given the task of preparing the nomination document (Fig. 1;
Mikkelsen & Ingerslev 2003). A decision as to whether
`Ilulissat Icefjord' will be awarded World Heritage List Status
Jakobshavn Isbræ,West Greenland: the 2002-­2003
collapse and nomination for the UNESCO World
Heritage List
Anker Weidick, Naja Mikkelsen, Christoph Mayer and Steffen Podlech
Fig. 1. Extent of the nominated area of `Ilulissat Icefjord' (red boundary lines). The ablation area and front of the glacier Sermeq Kujalleq are included,
together with the entire icefjord area. Modified from Mikkelsen & Ingerslev (2003).
Geological Survey of Denmark and Greenland Bulletin 4, 85­88 (2004) © GEUS, 2004
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will be made at the annual meeting of UNESCO in June
2004.
The nomination document includes comprehensive doc-
umentation on observations and investigations of Sermeq
Kujalleq. This major glacier, or `ice stream', is situated in a
subglacial trough that in its outer parts reaches depths of
1500 m below sea level (Iken et al. 1993; Clarke & Echel-
meyer 1996), and it can be traced inland for about 100 km
(Echelmeyer et al. 1991). General descriptions of the outer
part of the glacier stress the quasistable conditions of the glac-
ier front throughout the second half of the 20th century
(Stove et al. 1983; Echelmeyer et al. 1991; Sohn et al. l997a,
b). However, during an inspection visit to the nominated area
in August 2003 radical changes in the situation of the glacier
front were found to have occurred compared to the descrip-
tion set out in the nomination document (Fig. 2).
Prehistoric variations of Sermeq Kujalleq
At the beginning of postglacial time (c. 9500 B.P.) the front
of Sermeq Kujalleq was situated at the mouth of the fjord,
about 50 km west of the front position shown in Fig. 1, rest-
ing on a bank near Ilulissat at depths of 200­300 m below
present sea level (Weidick 1994). Subsequently, the ice mar-
gin retreated some 65­70 km, and at the end of the climatic
optimum c. 5000 years ago the glacier front was located
about 20 km east of the ice margin position of 1964 (Weidick
et al. 1990, fig. 4).
The following neoglacial readvance culminated during the
Little Ice Age (A.D. 1500­1900), with the maximum posi-
tion of the glacier front in 1851 (Fig. 3; cf. Bauer 1968).
Since the postglacial climatic optimum the ice margin is pre-
sumed to have advanced in pulses, such as it has been docu-
mented for the ice margin 40 km north of Sermeq Kujalleq
where the response of the ice-sheet margin has been calcu-
lated for the last 1400 years (Reeh 1983). There may have
been two periods of advance: at A.D. 700­800 and during
the Little Ice Age (A.D. 1500­1900).
Historical records of Sermeq Kujalleq
Historical records of the glacier fluctuations of Sermeq
Kujalleq have been collected and described by Larsen &
Meldgaard (1958) and Georgi (1960). The numerous obser-
vations since the beginning of the 1700s and up to 1851 sug-
gest a gradual advance during this period.
Subsequent to 1851 observations and descriptions are
more frequent and more detailed. The first mapping of the
frontal position was by Rink in 1851 (Rink 1857), the first
determination of the fast movement of the glacier front was
made in 1875 (Helland 1876), and seasonal fluctuations of
the glacier front position were recorded by investigations in
1879­80 (Hammer 1883). Regular meteorological observa-
tions were begun in the town of Ilulissat in 1873.
The quasistable period of Sermeq Kujalleq
1950­2002
Recessional positions of Sermeq Kujalleq are summarised in
Fig. 3. The recent part of the curve is based on aerial pho-
tographs (from about 1950) and since 1962 also satellite
information (Sohn et al. 1997a). This well-documented 50-
86
Fig. 2. Sermeq Kujalleq on 28 May 2003;
glacierfront indicated by dashed red line.
Satel-lite image by ASTER (Advanced
Spaceborne Thermal Emission and Reflection
Radio-meter) installed in the Terra satellite,
with the position of the glacier front on
7 July 2001 indicated by dashed black line.
ASTER data are distributed by the Land
Processes Distributed Active Archive Center
(LPDAAC), located at the United States
Geological Survey's EROS Data Center:
http://lpdaac.usgs.gov
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year period coincides with a stable position of the glacier
front at a broad part of the fjord. The quasistability of the
glacier front position was probably influenced by subglacial
topography (Echelmeyer et al. l991; Weidick 1992).
The thinning of the glacier during the recessional period
c. 1850­1950 has been estimated at more than 200 m (Weidick
1992), while observations on subsequent changes in thick-
ness of the glacier front are few and scattered. A lowering of
the frontal surface may have occurred from the 1960s to the
1980s (Echelmeyer et al. 1991). Between 1993/94 and
1998/99 investigations of the glacier by laser altimetry
showed Sermeq Kujalleq to be one of the few Greenland out-
lets showing signs of slight growth (Abdalati et al. 2001).
However, since 1997 a sudden transition to a rapid thinning
has occurred, starting in the lower reaches of the glacier and
spreading gradually inland. By 2001 almost the entire glacier
up to elevations of 2000 m exhibited thinning (Thomas et al.
2003). Substantial changes of the glacier front were therefore
not entirely unexpected.
The break-up of the Sermeq Kujalleq front
The inhabitants of Ilulissat had observed an unusual amount
of detached parts of the glacier front at the mouth of the ice-
fjord in 2002, and observations during the 2003 visit showed
that these parts are the result of a break-up of the floating
glacier front.
To date more closely the time of glacier break-up and
retreat of the front, studies were made of a series of Landsat
images covering the years 2001 to early 2003. It was estab-
lished that the last winter advance of the quasistable period
took place in March 2002, and was followed by a period of
continuous break-up and recession of the glacier front. By
May 2003, the glacier front was situated c. 11 km east of the
`normal' winter position. Major parts of the floating glacier
described by Echelmeyer et al. (199l) had disappeared.
Two stages in this break-up are illustrated in Fig. 2 (July
2001 and May 2003). The `normal' retracted summer posi-
tion of the quasistable stage (July 2001) was followed by the
last winter advance of c. 3.5 km to March 2002. In May
2003, a major recession of the glacier front has occurred, and
the glacier segment in Tissarissoq had become isolated and
had partially disintegrated.
The frontal position after 7 July 2003 is currently uncer-
tain, but recession seems to have continued and it is now
approaching the retracted position of the climatic optimum
4000­5000 years ago. The occurrences of marine shells in the
neoglacial moraines surrounding Tissarissoq demonstrate
that the area was ice-free in the past, although the duration of
this ice-free period is not known. A single radiocarbon dating
87
Fig. 3. Top: Approximate recessional
positions of Sermeq Kujalleq. Modified from
Bauer (1968). Bottom: Conceptual reces-
sional curve of the Sermeq Kujalleq glacier
front, based on the positions given by Bauer
(1968) up to 1964. The younger parts of the
curve are based on satellite information by
Stove et al. (1983), Sohn et al. (1997a, b) and
later Landsat and ASTER images. The width
of the curve depicts range of seasonal
variations in the position of the glacier front.
Note the rapid break-up and retreat from
2002­2003. Bauer (1968) and Georgi (1960)
give very advanced positions of the front in
1870 and 1880; both were considered
uncertain by Engell (1904), and have
therefore been omitted here.
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88
of a walrus tusk is currently available (4290 ± 100 B.P.;
Weidick 1992). Local legends record that this area was for-
merly ice-free and used as a hunting locality (Hammer 1883,
p. 5). If these legends record a real event, then the end of the
open-water period and advance of the ice may be as recent as
the Little Ice Age (A.D. 1500­1900). This can only be veri-
fied by extensive dating of the marine deposits, such as that
carried out to determine the duration of open water in
Nioghalvfjerdsfjorden in North-East Greenland (Bennike &
Weidick 2001).
Acknowledgement
The nomination project received financial support from the Danish
Ministry of the Environment as part of the environmental support pro-
gramme Dancea ­ Danish Co-operation for Environment in the Arctic.
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Authors' addresses
A.W., N.M. & C.M., Geological Survey of Denmark and Greenland, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark. E-mail:
awe@geus.dk
S.P., Department of Geophysics, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen Ø, Denmark.

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