History repeating itself?
14th February 2015
Not often troubled by ‘hangfire’ avalanche activity in Scotland, or anywhere else in the world for that matter. There’s evidence that Thursday’s full depth avalanche in Coire Ardair has shed quite a few extra sizeable chunks as the crownwall is looking a bit different now. In most situations once the avalanche has occurred all the tension is taken out of the snow in the vicinity of, and in particular above, the crownwall. Not in this case though.
March 2010 avalanche path in white. Feb 2015 avalanche track in solid grey. Black lines represent crownwalls.
Green broken line shows present tree-line. Thursday’s avalanche in purple. March 2010 avalanche path in blue.
The question we received in our last post about the 2010 Coire Ardair avalanches got me thinking more about the impact of avalanches in this location. The images above show the areal extent of the avalanche events in both years. It seems pretty clear that repeated avalanche activity over the decades (centuries?) here is making a significant and permanent dent in part of the tree-line immediately below the two re-entrants – and the mapping shows this fairly clearly, I think. Shows up well on the 1:50000 map, too. I wonder if historical maps of the area show this effect as clearly?
(You’ll occasionally see ‘Balloon Gully’ as a location for our formal snow pits and it’ll be here, high in one or other of these two steep re-entrants.)
I’ve seen avalanche paths devoid of trees in otherwise heavily forested areas of the Alps and in North America but not noticed them before in the UK. If you know of any native examples I’d be interested to hear more about them and their location.
Quite hard going breaking trail in soft wet old snow in places below about 450m today, as shown above. Well worth making significant deviations from your planned direct route and keeping to the heather/grass where possible at low altitudes. Much firmer underfoot conditions on snow-ice above 550m and beyond.
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Grant Duff
14th February 2015 11:42 pm
Once again great blog and information. Excellent stuff.
Mo Richards
15th February 2015 1:53 pm
Excellent information which is well illustrated.
meagaidhadmin
15th February 2015 5:13 pm
Hey, Mo!
A familiar name methinks! Many thanks for your kind comment.