2009 - Snow-patches Surviving On Scottish Mountains

[Thundery wintry showers]

I'm not too surprised at that, as I can guess at the culprit:

http://www.wetterzentrale.de/archive/ra/1994/Rrea00119941212.gif

Very wet in west Scotland and 16C across Tyneside during that spell, with record temperatures in places.

What does surprise me is that 1994 and 1995 were both very good years for snow patch retention, despite 1994 having the record-breaking warm November and the aforementioned episode in December, and 1995 had that hot summer and then a warm October with frequent SW winds across Scotland. Can you remember what caused good survivals in those years- was it the sheer amount that fell in the two preceding winters?

[firefly]

Can you remember what caused good survivals in those years- was it the sheer amount that fell in the two preceding winters?

1994's winter snowfall was huge. Patches survived that ordinarily would have disappeared in August! For instance, take this photograph from the 23rd May 1994 which looks from the Grey Corries westward towards Aonach Mor and Aonach Beag (with Ben Nevis in the background). The amount of snow in Coire an Lochain in Aonach Mor (to the walker's left, farthest away) is just mind-boggling. I've speculated that the depth of snow there must be approaching 50ft: possibly more. And this is in late May! Similarly, this picture from the 7th August of Garbh Choire Mor, Braeriach, shows the corrie absolutely loaded with snow. More similar to late May in a normal year.

Over 50 patches survived in 1994, and it would have been more had the mild December weather not melted a few of the lower-lying ones.

When so many patches survive a hot summer and mild autumn, you can be sure that the main factor is sheer volume of snow that fell in the previous winter. 1994 was a perfect example of this.

[firefly]

Thanks to the efforts of others we now have an excellent record of all remaining snow as of the 18th October. Alan Halewood, the mountain guide, visited Aonach Beag on the 17th to find that the snow is still there, and about 25m long x 15m wide x 2m deep. When you consider this patch was just shy of 50m long on the 22nd of August, it's astonishing to think it's still the size it is. However, it's now smaller than it's been since it last melted in 2006. A good photograph of the snow can be seen here.

The snow was rock-solid. Alan said that he could not even get a single finger into the snow, and that he would have needed an ice axe to traverse it. Secondly, absolutely no melting was observed, despite the conditions in the sun being fairly comfortable. Of course, Aonach Beag won't get any sun, and probably hasn't seen any direct sunlight in months (does it get any?!). More pictures from Alan's trip can be found in my flickr archive, here.

Also on Saturday the 17th, Attila Kish went up Garbh Choire Mor, Braeriach. He found the snow slightly smaller than when he and I visited on the 26th September, but not by a huge amount. The snow that also fell during the first week in October has filled up the bergschrund and is itself now very hard, having undergone several freeze-thaw cycles. The Sphinx patch (Britain's longest lasting) was 10m wide, and the Pinnacles patch was about 20m long. All pictures of this expidition are here.

Feeling energetic, Attila ventured up Observatory Gully the very next day and got some fabulous pictures of the remaining snow there. The notes have dimensions on them, rather than me trot them out here.

By my arithmetic, the total length of all snow on the 18th October (no material melting on the 17th due to cold, clear conditions) was 104m, worked out as follows:

1) Sphinx 10m

2) Pinnacles 20m

3) Aonach Beag 25m

4) Observatory main patch 20m

5) Observatory main patch lower 5m

6) Observatory lower right patch 1 15m

7) Observatory lower right patch 2 4m

Observatory lower left patch 3m

9) Point 5 Gully 2m

The current mild weather on the hills makes it impossible to say that these will all survive. Point 5 Gully's snows will most probably now be gone, and I'd expect a few of the others to vanish before lasting snow arrives.

Edited October 21, 2009 by firefly

[Norrance]

The last few days have certainly been mild and also wet and windy at times. With the forecast loking like a continuation with warm nights and either wet, mild and windy days or mild and dry days are the smaller patches now in danger?

From what I remember you said last year the lasting snows arrived in the Cairngorms in early October and in the Nevis area by late October. This year it looks like it could be substantially later?

Surely the bigger patches will survive?

[firefly]

Lasting snow came to Garbh Choire Mor last year on the 1st October, with Ben Nevis being around 3-weeks later.

This year is - obviously - going to be later. I understand the charts are showing cold weather with precipitation coming in during the first week in November. Perhaps someone can clarify that for me?

This morning’s temperature on Aonach Mor (around 1 Celcius) is encouraging, as is the temperature on Cairn Gorm (around 2 Celcius). Obviously this will fluctuate over the course of this week, but temperatures in low to mid single figures shouldn’t be catastrophic for at least the larger of the patches. I’m sure the smaller Observatory Gully outliers will suffer, but the two large ones should be OK well into November. I think that Aonach Beag is more at risk, but I still think there is enough there to get a good way into November.

I'll be visiting Aonach Beag this weekend coming so I'll update on that.

If the snow does arrive during the first week in November then I would expect there to be 5 or 6 survivals. If mild weather drags on through November then we could be looking at just a couple.

[Norrance]

The Met O forecast is continuing mild for the first week of November but becoming steadily colder from then on.

Regards

Nor.

[multi cellular thunderstorm]

The Met O forecast is continuing mild for the first week of November but becoming steadily colder from then on.

Regards

Nor.

Looks like it could get cold enough for snow next week on the mountains, with some chilly NW winds.

I'm on holiday up there next week and I was hoping for more settled chilly weather, but I guess unsettled will have to do, as long as there's a bit of snow I won't mind.

[firefly]

Can there still be snow from last year on Scotland's mountains?! Surely the recent mild weather, coupled with the monsoon conditions has done for the remaining snow? Happily, due to visits over the course of the last few days by hardy souls, I can report that there are still 6 (possibly 7) patches of snow clinging on for dear life in the Highlands.

Firstly, my Ben Nevis buddy Mark Atkinson made a trip on the 28th October to Observatory Gully, where he found the following...

The biggest patch was in the region of 9m long, but all the snow is horribly exposed, as you can see from othere pictures here.

I visited Aonach Beag on Saturday to find a 19m x 12m x 1m patch. Absolutely rock solid snow there, doubtless because of its age (almost 3-years now).

More pictures of my trip are here.

Garbh Choire Mor was visited on Saturday the 31st by Davie Duncan, and he reported the snow in good condition, though still melting (albeit slowly). Sphinx patch was 7m x 7.7m x 1.5m, and Pinnacles by 17.9m x 7m x 0.4m. No pictures of that yet, but I'll try and get a couple.

Will they all survive? My own view is that the ones longer than 5m will. The only ones in danger (I would guess) are the smaller Observatory Gully patches. The weather forecast this week is for cold weather with snow above 1000m or thereabouts. MWIS predicts, though, that rain may return in time for next weekend.

Watch this space...

[Norrance]

Question for Firefly. Is there a possibility that the snow that has fallen on the higher hills this week may be the lasting snows this Winter?

If so how many patches made it through?

If the patch on Ben Nevis has broken up and survived in bits does it count as one or as the number of smaller patches?

Regards

Nor.

[firefly]

Hi Norrance.

It looks very much as though the snow that has fallen in the Cairngorms will be lasting snow for Garbh Choire Mor (see below).

.

However, the situation is not quite as cut-and-dried as that in the west. Although there is a decent covering on Ben Nevis, there's not enough to say for sure. The charts show, apparently, that there is no appreciable snow on the way. We could be looking at mid-November before we know for sure.

That said, there will be next to no melting occurring, and the snow that is still extant is likely to persist.

[Norrance]

Thanks Firefly,

Still a question of wait and see then.

Nor.

[La Bise]

Very enjoyable topic and great work by Firefly. I've been puzzled by those snow patches in the Scottish mountains ever since my first visit there a summer a few years ago, I could not believe there was snow surviving as such low altitude and in a maritime temperate climate!

[shuggee]

Saw my first snow of the season this morning on top of the Trossachs, viewed from the train from Edinburgh to Glasgow Queen Street. It was clear blue skies and the sun was just rising with the tops of the mountains picked out in blazing light - ordinary folk on the train were even commenting. Lovely jubbly

[johnny1972]

Morning All

After the mild weather throughout the majority of Autumn we now have the start of nearer normal temperatures resulting in snow falling close to base level at Cairngorm as can be seen on this mornings web cams on www.winterhighland.co.uk

[JRMcLeod]

Surely thats the snow lasting all winter now with the deposits over the past few days???

[Zerouali lives]

Yeah, I'd say so.

What's important is the wind direction - encroaching from a SW'ly direction today and tomorrow - I guarantee there will be huge deposits of snow in eastern gullies of Ben Nevis after today's heavy falls, with more to follow tomorrow, and then sme freeze action over the weekend.

[firefly]

Firstly, thanks to eveyone who's been keeping an eye on this thread. Secondly, this will now be the last post of 2009. Yes, lasting snows have arrived, and some snow patches have indeed survived on Scotland's mountains. In actual fact, lasting snow arrived a few weeks back, but in the absence of heavy snowfall to make 100% sure, we were wary of coming out and declaring it for certain.

So, where did snow survive, and how many patches made it?

Six patches of snow made it through, in three locations. Three at Observatory Gully on Ben Nevis, two at Garbh Choire Mor on Braeriach, and one at Aonach Beag.

The largest patch to survive (in terms of surface area), was on Aonach Beag in the Ben Nevis range (location here, you can zoom in or out). Lasting snow came there on the 8th November, and photographs of a trip made the day after by John Pottie can be found here. Although much smaller this year than 2007 & 2008, it was still larger than any other (approximately 16m x 8m). It has now persisted through three summers/autumns, which has not happened for a long time indeed. Probably since the 1970s.

Three patches survived at Observatory Gully on Ben Nevis, and lasting snow arrived there on the 4th November. Alan Halewood's photographfrom that day shows a good cover, with a couple of the small patches buried, but the main one (at the base of the shallow cliffs in the middle of the picture) is still visible. The smallest of these patches would have just survived.

The last two, known as Sphinx and Pinnacles (after rock climbs above them), survived at Garbh Choire Mor, Braeriach. These are Britain's longest-lying snows, and lasting snow arrived there on the 1st November. Sphinx patch (always the last to melt in Scotland), has now melted just 5 times in the last 100 years: 1933, 1959, 1996, 2003 & 2006.

The short-term trend, therefore, since last melting in 2006 is that of a general upward trend in numbers, with this year dipping slightly. There were 9 in 2007, 12 in 2008 and 6 in 2009. The shockingly wet summer did not, as I feared it might, destroy all the snow. Had the snow not survived in 2007 & 2008 then the rain may have done. The fact that some patches were getting on for 3-years old (and were icy hard) may have given the old snow the resillience to withstand the continual pounding.

If anyone has any particular questions on any aspects of what I've written over the months then please post on here and I'll do my best to answer them!

Cheers,

Iain Cameron

[BIG LAD]

really enjoyed following this thread. thanks to everyone for making the effort to monitor patches. great work!

[SNOW-HEATWAVE-YES]

I've been following this thread all year. Thanks for all the posts.

[Norrance]

Hi Firefly,

Thanks again for keeping this thread going.

I have had an interest in snow patches since I was a youngster in the sixties in Highland Perthshire and could see several Munro's from my bedroom window. Later I used to drive and walk some hills [mostly locally] basically to find patches. Only in the last few years, thanks to the internet, I realised that they are actually monitored on a scientific basis. Unfortunately due to a serious neck injury I can no longer climb the hills myself[though I still look from road levels] so I have found this topic fascinating.

What I want to know is if there is one book or website that gives historical records of the surviving snow patches and even better if the locations are also given.

Thanks

Nor.

[firefly]

Hi Norrance,

There was a paper published in 2002 in "Weather" magazine entitled 'Snow patches lasting until winter in north-east Scotland in 1971-2000' (Adam Watson, Richard W. Davison, John Pottie; Volume 57, Issue 10 , Pages374 - 385). This paper gives each location where snow survived and how often it survived. In addition to this, Adam Watson has a (yet unpublished) paper which gives every location in Scotland (1942-1970 in north-east Scotland, and 1945-2009 for west Scotland) where snow has been known to persist through the year. I have this document, and it's fascinating. Hopefully it'll be published next year. I'm also working with Adam on a paper which seeks to demonstrate the historical evidence of far more snow in the last few centuries than we get now. Again, this should be published next year.

1951 was the year where more patches survived than any other year in 1938-2009 inclusive. That year, 142 patches survived in north-east Scotland, and 9 lay at <900m. We have no similar records for west Scotland, but it is highly likely that many survived. It would not be an exaggeration to say that 200 patches would have survived that year in total: a phenomenal amount. 1967 was also a fantastic year for suvivals, and more recently 1994 and 2000.

We are due a bumper year any time soon!

[Thundery wintry showers]

1967 is quite a surprise as that was a pretty mild winter. I guess frequent wet "westerly" type weather in December 1966 and March 1967 must have contributed somewhat.

I'm not surprised at 1951- most of that winter was very wet and cool zonal (with a very cold northerly-dominated December)- ideal for big snowfalls at high altitudes.

As a subscriber to Weather through the Royal Meteorological Society I will certainly be interested in reading these upcoming papers.

[trickydicky]

1967 is quite a surprise as that was a pretty mild winter. I guess frequent wet "westerly" type weather in December 1966 and March 1967 must have contributed somewhat.

I'm not surprised at 1951- most of that winter was very wet and cool zonal (with a very cold northerly-dominated December)- ideal for big snowfalls at high altitudes.

As a subscriber to Weather through the Royal Meteorological Society I will certainly be interested in reading these upcoming papers.

Apparantly, I believe it says it in the winter section of this website somewhere, Dalwhinnie had 101 days of snow cover during the 1950/51 winter. Thats pretty much the whole winter. Impressive for zonal type weather. If it stuck around that much at 1000ft then there must have been no thawing whatsoever at 3500ft+, no wonder so much remained through the summer.

[stewfox]

We are due a bumper year any time soon!

Funny I joined this forum after looking via google on the subject of snow patches surving in Scotland.

Like many others have mentioned I appreciate all the efforts.

I also interested in what could help to constitutes to a bumper a year.

I assume lots of winter and late spring snow?

A cool summer and lack of rain and or sun?

Sun I guess isn't a big factor in late autumn but I assume if at 55N + it is in summer even on north facing slopes?

I guess mild temps with heavy rain through the summer? But then rain could bring mountain snow late August early September ??

E.g. what was 1976 like?

[Norrance]

Thanks for your reply Firefly. I am looking forward to reading anything that is published about the patches.

I can at least partly answer Stewfox's query about 1976. Despite the long hot Summer the weather changed suddenly and the lasting snows on the higher reaches of the Cairngorms came in the second week of that September that year. Therefore the patches didn't have to last as long as usual to survive.

Edited December 3, 2009 by Norrance