Snow Patches On Scottish Mountains

[Styx]

The photograph shows a piece of ground that, before 1959, was last exposed in 1933 (i.e. the last time the snow melted). So in essence the snow-patch that was present in 1959 contained all the muck, dirt and general detritus that being 26 years old entails. As the snow melted, it deposited all this detritus on the rocks and ground it was lying on, giving the impression of having been given lick of black paint. Sandy Tewnion, the photographer, commented that the black residue was like tar. Not sure why that was, as I'm no expert.

The most likely explanation is that it's nothing more than good old fashioned dirt!

Incredibly interesting!

I would love to see this subject turned into a TV documentary. I could really see it working!

[Alternative Ulster]

Sandy Tewnion, the photographer, commented that the black residue was like tar. Not sure why that was, as I'm no expert.

Pollution? Heavy industry and the rise of motor car.

[spindrift1980]

Back to the Cairngorms again today!...

Still a healthy 50+ patches visible on those hills which it is possible to see from Carn na Drochaide, just north-west of Braemar. Not a huge amount of melting in the last week, which has seen temperatures not much above freezing on the tops at some points. Warming up though, and tomorrow looks like having some rain plus the 'hairdryer' south-west winds which have been absent for a while. Hopefully there should be a decent amount still around by 1 August when Firefly and his colleagues do their next Scotland-wide survey though.

Some photos from today (will link to the others later for those who are interested):

Laird's Tablecloth, Beinn a' Bhuird:

The smaller, shallower patches have taken a hit since last week but the main patch not much changed.

Coire nan Clach, Beinn a' Bhuird:

Ben Macdui:22 patches visible from this angle but I believe there are others still on the Macdui/Cairn Gorm plateau

Beinn Mheadhoin: Forgot to mention last week that there is still at least one patch on this remote mountain

[firefly]

Though summer has arrived in parts of England, the high hills of Scotland remain cool (currently 4.8 degC on top of Cairn Gorm). Now that August is almost upon us, we're getting down to brass tacks in terms of snow patches. Most of the ones that remain are small, except the usual 'biggies' on Ben Nevis and the Cairngorms.

The biggest surprise for me recently was to discover that, as of the 21st July, a small patch of snow persisted on An Stuc, a hill in the Ben Lawers region. This patch was already small on the 25th June (see here), but persisted until almost a month later (see here). It just goes to show that snow which is 'dug in' in a hollow can prove very resilient to melting. Of course, cool weather helps, but patches I've seen that I hadn't given much hope for have endured way beyond what I'd have thought.

Another example of this was found at Glencoe ski area (on Meall a' Bhuiridh). On the 12th July, only two tiny patches remained on that hill (here). Remarkably, a tiny vestige remained until the 22nd, fully 10 days of summer weather without succumbing completely.

There are other areas where snow persists as I write, and I'm conducting a Scotland-wide survey on the 19th and 20th of August. If anyone is planning a jaunt to the Highlands on these dates then please let me know, as I may ask them to keep an eye out on specific locations!

Garbh Choire Mor, 21st July. Britain's snowiest place.

[firefly]

Another update for all you chionophiles out there...

August is now well and truly upon us. Snow is confined to some of the very highest nooks and crannies of the Scottish hills. In fact, you can almost count on two hands the mountains that have snow on them still. Most of these are in the Cairngorms and Nevis range, but there are a few 'regulars' which cling to their snow, even though they are unlikely to still show it after the end of this month.

Hills where snow is still present (at time of writing):

Nevis range

1. Ben Nevis

2. Aonach Mor

3. Aonach Beag

Cairngorms

1. Beinn Bhrotain

2. Beinn a' Bhuird

3. Ben Avon

4. Braeriach

5. Ben Macdui

6. Cairn Gorm

Others (maps are rough locations of where the snow is)

1. Sgurr nan Clachan Geala

2. An Riabhachan

3. Tom a' Choinich

4. Geal-charn

The observant amongst you will notice that most of these patches face east, showing the prevelance of snow from the west this winter. This is crucial if snow is to persist through summer. East facing snows are more sheltered from the summer sun (beneath tall cliffs, as they tend to be) and less likely to be hammered by SW 'hairdryers' during the warmest months.

Oh, congratulations are due to Helen Renni (h11lly), who has notched up her 34th consecutive month of skiing in the Cairngorms. She ventured up to Ciste Mhearad last Friday (3rd) to ski on some pretty deep snow. My favourite picture from that day is shown here. Glacier like!

The snows on Ben Nevis and Garbh Choire Mor (Braeriach) are still extensive, the latter especially. Some good photographs of the snow can be seen in this trip report from the 31st July.

I am again organising a Scotland-wide survey of all remaining snow on the 19th and 20th August, covering the mountains listed above. I shall post the results on here. If anyone is in the hills of Scotland that weekend then do make yourself known to me!

[summer blizzard]

How would you place the chances of survival into September?

[firefly]

How would you place the chances of survival into September?

Which hill?! Snow will certainly persist into September on at least 3 of these hills, and possibly (probably) more.

[summer blizzard]

It was a general question.

Good to here.

[firefly]

It was a general question.

Good to here.

You can generally always find snow in Scotland if you know where to look. Even in very hot summers the snow doesn't always melt (a la 1976).

[stewfox]

Which hill?! Snow will certainly persist into September on at least 3 of these hills, and possibly (probably) more.

Do you think more so then last year (patches surviving).

When is it regadred as 'safe' for patches to remain mid october or does one have to wait till November ? Great posts

[firefly]

Do you think more so then last year (patches surviving).

When is it regadred as 'safe' for patches to remain mid october or does one have to wait till November ? Great posts

It's still early, but I'd be very surprised if we didn't get at least a few survivals this year. Garbh Choire Mor looks healthier than at any time since 2008. I'll have a better idea after the survey on the 20th.

In 1994 lasting snow didn't arrive until December! Some patches were still melting in November in mild weather. The moral of the story is that it's impossible to predict when snow is finally 'safe' this far in advance.

[firefly]

Monday the 20th August saw a Scotland-wide survey of all remaining snow patches. A small army of volunteers was mobilised to cover ground stretching north to south and east to west. Numbers of patches in the last few years have hovered around the mid 30s during the August survey. As we suspected, though, the SW, W & NW direction of snowfalls that fell during the winter of 2011-2012 (coupled with the frequent freeze/thaw cycles) meant that the traditional (i.e. east facing) long-lying snow locations did rather well.

So, what mountains carried snow?

Nevis range - 32 (19 Ben Nevis, 10 Aonach Beag, 3 Aonach Mor) patches

Beinn Bhrotain - 4 patches

Sgurr nan Clachan Geala - 4 patches

Tom a' Choinich - 1 patch

Toll Creagach - 1 patch

Beinn Dearg - 1 patch

Macdui/Cairn Gorm - 19 patches

Braeriach - 8 (7 in Garbh Choire Mor, one in Coire Bhrochain)

Geal-charn - 1 patch

Total - 71 patches

The snow ranged from tiny patches to very large wreaths. The largest of which measured 98 metres (Garbh Choire Mor, Braeriach, below):

The deepest snow to be found by us on Monday was that at Ben Nevis's Observatory Gully. It is somewhere in the order of 8 metres deep. This snow, however, sits on rocks and not soil. This means it is prone to being melted both from above and below. What this means in practise is that it will almost certainly melt before the snows of Garbh Choire Mor, which sit on soil. Anyway, the picture below shows the depth present on Ben Nevis. It isn't a glacier, though it resembles one!

The prognosis for the snow this year is looking reasonable. The amount of warm weather is pretty normal for the time of year, and normal service now seems to have been resumed (unsettled in the north). If this pattern continues for the rest of the summer and early autumn then I think we could see a reasonable amount of survivals in the usual places (he says, tempting fate)!

[Polar Maritime]

Thanks for the update Firefly, such an interesting subject as a keen mountaineer in the highlands myself in the winter season. It's always good to know that any remaining snow patches give things i head start for the upcoming season. Do you have any idea when Observatory Gully last lost it's remaining snow pack?

Thanks in advance, and for the hard work that must be involved to collect this kind of data.

[firefly]

No problem.

Observatory Gully was last snow-free in October 2006. It has held snow every since, albeit not in the same place. It almost vanished last year and the year before, but just hung in by the skin of its teeth!

[Polar Maritime]

Thanks firefly, looking at this picture of Observatory gully from 2008 taken exactly 4 years ago to the day it certainly looked in better condition. Fingers crossed this year it will hold on !

[firefly]

That's true but if you look at 2011 you will see the snow is virtually identical:

...and! 2010 substantially worse:

[firefly]

MWIS has just mentioned snow for the first time in a couple of months...

Thursday, 30th August, 2012

Risk showery rain, mainly north

Showers, mainly afternoon, but over

the Cairngorms there may be

intermittent rain for a few hours. Later

snow on highest summits.

[Gavin Hannah]

Oh yea, here it comes!!!

[summer blizzard]

MWIS has just mentioned snow for the first time in a couple of months...

Thursday, 30th August, 2012

Risk showery rain, mainly north

Showers, mainly afternoon, but over

the Cairngorms there may be

intermittent rain for a few hours. Later

snow on highest summits.

Just wonder what 850hpa temperature should be looking at for September snow up there?

[East_England_Stormchaser91]

Some models suggesting we are to get a plunge of Arctic air by the 2nd week of September with 5c isotherm sweeping the whole country! This will be a shock to the system if it happens! Looking over towards Eastern Iberia, and the chance of what is known as a 'Gota Fria' event happening around Costa Blanca, Brava and the Balearics in a couple of days time, torrential storms are caused due to much cooler air from the N and NE going over a very warm Mediterranean Sea.

[johnholmes]

the cold front gives a taste of winter for the Alps as it moves SE

the Jungfrau area at about 6000ft is predicted to have temperatures -1 to +3C and 20mm of precip Thursday into early Saturday, so a good covering before it thaws!

[firefly]

Just wonder what 850hpa temperature should be looking at for September snow up there?

Realistically, around 0 degrees. I'm no expert on this sort of thing, but 850hpa equates to around 5000 ft or so?

[The watcher]

Around 1500metres Firefly. So Yes around 5000ft.

Edited August 28, 2012 by The watcher

[Gavin Hannah]

Carirngorm mountain and Ben Nevis are both of 4000ft.

[firefly]

1,245 and 1,343 metres respectively! Or, if you prefer old money, 4,084 and 4,406 feet. The mean temperature on top of Ben Nevis was measured at a fraction below freezing during the years of the observatory. A tad warmer nowadays, so probably in the region of 1degC. However, the Cairngorms are more likely to see early snow because of their position relative to the cold northerly weather systems that can rattle in from the Arctic in September. 2010 and 2011 witnessed snow on Ben Macdui on August 28th. It would be very unusual to have a run of 3 Augusts where snow fell, but MWIS is still stating that snow could fall on the afternoon/evening of the 30th.

During a run of 69 years Adam Watson has seen fresh snow lying on the Cairngorms in 12 Julys, and in 69 years (excluding the current August) he has noted it in 10 years, with 4 August days the most in any one year (2011). August is undoubtedly the least snowy for fresh snow lying, and the middle part of the month the least of all. August snowfalls have been fairly light, but some in early July have been heavy with much drifting, as in 1948 and especially 1978. June is the third least snowy month, and September the fourth least.