Jökull - 01.12.1978, Page 33

fjörður hafi orðið jökullaus á Saurbæjarskeið-
inu (fyrir 11 —12 þús. árum) (Víkingsson 1976
og 1978). Samkvæmt því eru tveir möguleikar
á aldri garðanna norðan og norðaustan Hofs-
jökuls: 1) Sá elsti, Rauðhólagarðurinn, er frá
Búðaskeiði (10—11 þús. ára) en allir hinir frá
byrjun nútíma (9—10 þús. ára). 2) Engin
ummerki um Búðaskeið finnast á þessum
slóðum og allir garðarnir því frá byrjun nú-
tíma.
The Surface Area of Glaciers in Iceland
HELGI BJÖRNSSON
Science Institute, University of Iceland
The area covered by glaciers in Iceland has
been measured on Landsat images and on air
photos. (Table I). The present glaciers in
Iceland cover about 11260 km2 or 10.9% of the
country. The total glacier area has shrunk by
about 5% since the maps were surveyed by the
Danish Geodetic Institute in the period 1903
to 1940 (Thorannsson 1958). In percentage the
shrinkage of the glacier area is smallest for the
largest (and thickest) ice caps. However, the
shrinkage of four small ice caps is negligible.
Eiríksjökull (max. altitude 1675 m), Thóris-
jökull (1350 m), Hrútfell (1410 m) and
Tungnafellsjökull (1540 m) are on isolated
plateaus situated high above the firn line with
steeply sloping outlet glaciers flowing down to
their relatively small ablation areas.
TABLE I. Surface area of glaciers in Iceland. — TAFLA I. Flatarmál jökla á Islandi.
Glaciers Jöklar Area Flatarmál km2 Landsat images from (date) Air photos from (year) Area 'Flatarmál km2 Maps surveyed Kort gerð year ár Shrinkage Jökulrýrnun percentage %
Vatnajökull 8300 19 Aug. 1973 8538 1903—04, 1934—38 2.8
Langjökull 953 5) 1022 1937-38 6.8
Hofsjökull 925 )) 996 1937-38 7.1
Mýrdalsjökull 596 >) 701 1904,1907, 1937-38 15.0
Drangajökull 160 1960 199 1913-14 19.6
Eyjafjallajökull 78 19 Aug. 1973 107 1937-38 27.1
Tungnafellsj ökull 48 22 Sept. 1973 50 1937-38 4.0
Thórisjökull 32 19 Aug. 1973 33 1937-38 3.0
Eiríksjökull 22 )) 23 1937-38 4.3
Thrándarjökull 22 9 Aug. 1978 27 1935—36, 1940 18.5
Tindfjallajökull 19 19 Aug. 1973 27 1937-38 29.6
Torfaj ökull 15 )) 21 1937-38 28.6
Snæfellsjökull 11 1960 22 1910 50.0
Hrútfell i 10 19 Aug. 1973 11 1937-38 9.1
Hofsjökull í Lóni 8 22 Sept. 1973 25 1935-36, 1940 68.0
Glaciers on Trölla-
skagi (115 in number) 40 1960 -60 1930-31 33
Other glaciers -20 -40 50
Total 11260 11900 5.4
ACKNOWLEDGEMENTS Surveying Department (Landmœlingar íslands).
The Landsat images were made available by Dr.
Richard S. Williams, U.S. Geological Survey and the
surface area of thefour largest ice caps was estimated
by him. The air photos were taken by the Icelandic
REFERENCES
Thorarinsson, Sigurdur 1958: Flatarmál nokk-
urra íslenzkra jökla. Area of the biggest
glaciers in Iceland. Jökull 8: 25.
JÖKULL 28. ÁR 31