This effectively means that current expert opinion is now firmly weighted against the existence of any glacial ice in the Cairngorms since the last ice age.

Sugden’s analysis of his fieldwork results took the form of dating of Rhizocarpon Geographicum lichen (commonly known as ‘map’ lichen due to its similarity to the visual appearance of a map of countries with borders separating them) growing in the corries, by measuring and comparing relative diameters of lichens - a technique known as lichenometry. This research is nearly half a century old now, so it is definitely time for an updated program of work to resolve the question of whether glaciers existed in any of these corries as recently as the period of the Little Ice Age.

In the comment above from March 18th, I questioned the validity of the assumption made in Sheila Rapson’s later research that glaciers always remove all traces of any organic material beneath them - in Sugden’s 1977 article, interestingly he comments ‘there are numerous situations in the world where glaciers have crossed weak deposits such as peat without removing them’.

In it, she points out that there are 18 coires in the Cairngorms (including the Lochnagar massif) that hold moraines, but that her radiocarbon dating and pollen analysis research (which I believe was originally done for her 1983 PhD thesis) was undertaken in only 3 of these corries.

She also specifically mentions Garbh Choire Mor of Braeriach (which contains the largest and longest-lasting perennial snowfields in the Scottish mountains, and which contains a moraine at a higher altitude than the other moraines in the Cairngorms) in the 1990 SMC journal article, singling out its moraine as being difficult to date, although she concludes that it is likely to be younger than the other moraines that have been dated to the age of the Loch Lomond Advance of c. 10,000 years ago.

Rapson points out that the David Sugden’s original lichen cover research from the 70s that prompted the theory that glaciers existed in the Cairngorms in the 17th century has not been completely negated by her later research, at least in the case of Garbh Choire Mor. She makes the tentative suggestion that ‘the coire, because of its high altitude, accommodated a true glacier during the Little Ice Age’.

As I mentioned in the previous comment, there is scope for further research work in this area, and I believe the question of whether glacial ice (perhaps ‘inactive’) existed in the Cairngorm mountains in the Little Ice Age is still open.

The full citation for the 1990 SMC Journal article is:

RAPSON S C. 1990. The age of the Cairngorm corrie moraines. Scottish Mountaineering Club Journal 34 (no. 181). 457–463.

RAPSON, S. C. (1985), Minimum age of corrie moraine ridges in the Cairngorm Mountains, Scotland. Boreas, 14: 155–159.

The paper is available online here (subscription required):
http://onlinelibrary.wiley.com/doi/10.1111/j.1502-3885.1985.tb00909.x/pdf

This paper argues that ‘active ice’ cannot have existed in 3 corries with boulder moraine ridges in the Cairngorm mountains since 6000-9000 years ago, as organic sediments retrieved from the lochs in these corries have been radiocarbon dated to those dates.

There is some scope here for further research though - an implied assumption has been made in this paper that ‘active’ glaciers, if they existed, would have completely disturbed or removed any trace of organic material in the corrie - but how true is this assumption?

Also, only 3 corries out of 30 in the area of the Cairngorm mountains have been investigated with these methods in this paper, because ‘only a handful hold boulder moraines’ - but again, how true is this? Coire an t-Sneachda certainly contains small moraine ridges (http://www.landforms.eu/cairngorms/coire%20Sneachda.htm), but is not mentioned at all in the paper, and I am sure there are others.

Interestingly, the paper does say that the corries may have contained ‘permanent snow’ during the period of the Little Ice Age but again, we’re back at the issue of definitions and labels that I touched upon in my more recent blog entry ‘The Scottish mountains: on the glacial ‘knife-edge‘.

This conclusion has now been discounted in current academic research, although this is probably still relevant:

“…it appears probable that the nearest approach to glaciation in the Scottish Highlands was reached in the 1740’s and again about 1809-18;…we cannot claim that a glacier is likely to have established itself.” (Manley G. 1949. The Snowline in Britain. Glaciers and Climate: Geophysical and Geomorphological Essays. Geografiska Annaler 31.)

“..the article by David Sugden where he suggested glaciers in the Cairngorms in the 1700s and one at Garbh Choire Mor in 1810, all on the basis of lichenometry. This has since been rejected in a paper by his PhD student Sheila Rapson describing further work by her.”

So it appears that the claim that glacial ice existed in the Cairngorms as recently as the 18th century may be unfounded.

http://www.jstor.org/stable/1797276

Another interesting (but from 1949 so it’s a bit old) paper on this topic can be seen at:

http://www.jstor.org/stable/520361

(Viewable only by subscribed users)

http://news.bbc.co.uk/1/hi/scotland/highlands_and_islands/7460879.stm

http://www.jstor.org/view/00167398/ap020723/02a00090/0

For the benefit of users without a subscription, here is the relevant passage from the paper:

“…it seems that extensive permanent snow beds or even inactive glacier ice existed as recently as the late seventeenth century.”

This conclusion is drawn by analysing lichen cover on rocks in the Cairngorm corries.

http://www.cairngorms.co.uk/parkauthority/papers/board/index.php

You might also be intersted in this other excellent site about the Cairngorms landscapes.

http://www.fettes.com/cairngorms/