Ever since Dave Sugden and I worked in the valley of Kaldalon in NW Iceland in 1960, I have been fascinated by Drangajökull, the ice cap that dominates the plateau to the NE of the valley. For very many years the ice cap has been shrinking, and is destined to go the way of Glamajokull, which used to exist on another segment of high plateau on the western side of Isafjardardjup.
In recent years there has been more work on the ice cap, and I culled a few images from the new papers. The ongoing shrinkage is inexorable, and all down to climate change -- and the glacier snouts (three of them) are just the most obvious places to look at what is happening. Up on the plateau, the ice edge is retreating year on year, and the above map shows how the old "subglacial surface" is gradually being exposed.
A recent satellite image of the ice cap, with the Kaldalon trough visible top right. To the left of centre are the small outlet lobes and glaciers of the Reykjafjördur - Leirufjördur area.
The nunataks on the skyline are on the NE side of the ice divide. This photo was taken in the Reykjafjördur valley.
Another reconstruction of the ice cap as it appears today.
It's interesting that a small and vulnerable ice cap like this one has outlet glaciers that are liable to surging behaviour. The 1750 position of the ice front in Kaldalon appears to have been located not far from the massive terminal moraine that almost blocks the valley. That big moraine has now been dated to the Younger Dryas. The 1750 position was possibly the outermost glacier position of the "Little Ice Age". Fragments of a smaller moraine (which we mapped in 1960 and which is referred to as Moraine 1 by Brynjolfsson et al, 2015) may have been constructed during the stillstand following a powerful surge, during which the ice flowed across fertile land that had been previously farmed. At any rate, since 1760 the glacier has retreated several kilometres as far as the trough head, which is nowadays partially exposed, with the overall retreat disturbed by several recorded short-lived advances which must be interpreted as surges. This has coincided with a halving of the extent of Drangajöll, down to 262 sq km.
Glacier snout positions in the Kaldalon trough, as reconstructed by Brynjolfssson et al, 2015. The snout position coincides with a substantial "valley-side esker" and a ridge of lateral moraine; inside the snout position is an extensive area which we referred to in 1960 as "The Trout Pools" -- essentially a wide expanse of pitted outwash, representing the meltout of detached ice masses during a period of rapid ice edge retreat.
The most substantial surge occurred in 1994-99, when the snout advanced by 1 km -- with a similar surge recorded in the Leirufjördur valley. That's an advance of 200m per year.
The surging behaviour of these glaciers ins intriguing, given the overall poor state of health of the ice cap itself.
Below are some Kaldalon images culled from the web, with thanks to the photographers. A magical place -- and it was even more magical in 1960, before the building of the road and the bridge.
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