Jökull - 01.01.2019, Page 8

Terminus lakes on the south side of Vatnajökull
Figure 3. The ice margin of Skeiðarárjökull at different times (dashed coloured curves with coloured year
labels) and glacial lakes in the foreland (coloured areas with white labels). The shaded glacier bottom topogra-
phy (Björnsson and others, 1999a; Björnsson, 2009a) shows that the main terminus lakes are formed in front of
troughs in the upstream bed topography. Green shading indicates bedrock elevation lower than the water level in
the terminus lakes. The shaded relief of the glacier surface is based on a lidar DEM from 2010–2012 (Jóhann-
esson and others, 2013). The digital image of the glacier foreland is from the ArcGIS Online basemap (sources:
Esri, DigitalGlobe, GeoEye, i-cubed, USDA FSA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo,
and the GIS User Community). Detailed maps of the two main lakes are shown in Figure 4. – Jaðar Skeiðarár-
jökuls á mismunandi tímum (slitnir, litaðir ferlar með lituðum skýringum) og þróun lóna við jökuljaðarinn
(lituð svæði með hvítum skýringum). Skyggður jökulbotninn (Helgi Björnsson o.fl., 1999a; Helgi Björnsson,
2009a) sýnir að lónin myndast í djúpum rennum sem grafist hafa í jökulbotninn. Græn skygging sýnir svæði
þar sem jökulbotninn er undir vatnsborði lóna við jökuljaðarinn. Skyggingin af yfirborði jökulsins byggir á
leysilandlíkani frá 2010–2012 (Tómas Jóhannesson o.fl., 2013). Upprétta loftmyndin af landi utan jökuls er frá
ArcGIS Online basemap (heimildir: Esri, DigitalGlobe, GeoEye, i-cubed, USDA FSA, USGS, AEX, Getmap-
ping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community). Þróun tveggja stærstu lónanna er sýnd á
4. mynd.
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