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la Niña

The UK shrouded in snow. <em>Picture: NEODAAS/University of Dundee</em>

The UK shrouded in snow. Picture: NEODAAS/University of Dundee

There is no such thing as a standard Scottish winter – but, if there is something approaching a traditional format, one seen more often than others, it is roughly as follows.

First comes wild-and-mild stormy weather in the couple of months before the festive season, but with not much snow apart from on the really high ground, 1,000 metres-plus. Occasional ice and mixed (or messy, or thin, or however you want to label it) conditions on medium-sized hills, and nothing much more serious than overnight frost at lower levels.

January brings the main snow-dumps, with the third week of the month tending to be seen as the critical stretch. Then February settles down into lovely anticyclonic weather, the lower ground starts to feel almost springlike, while the hills – now with a substantial base of January snow – go through freeze-thaw cycles such that everyone is happy and there are great on-hill conditions for walkers, climbers and skiers right through until after the clocks change.

That’s the template, sort of. But by pretty much any assessment, whatever it is we’ve been having this time around, it’s very much not that.

There has been a lopsidedness to proceedings. Late November until early January saw plenty of snow at all levels and disruptively low temperatures. Then the bulk of January was mild and placid, with a retreat of the snowline rather than a bulking-up of the snowpack. And now, the current wave of gales and stormy mayhem notwithstanding, it looks like we could end up viewing this as a wrong-way-round winter, a curiosity rather than a classic.

Or will we? At the start of December, The Caledonian Mercury took soundings from a couple of well-informed people as to how they saw the weather and outdoor-activity prospects over the coming weeks. Now seems a good time to go back and ask for a reassessment.

“It looks like we will be back into a spell of wet, windy and relatively mild weather for the next month or so,” says Alison McLure – former BBC weather reporter, now the national officer for Scotland with the Institute of Physics. “I suppose that will be a relief for the general population, but I miss the stunning clear blue days with crisp snow on the ground.

“I was surprised at how quickly the snow melted from the hills, although hopefully the higher climbing routes will stay in good condition. It feels like we are back to the more ‘normal’ winters of the last 20 years or so. However, if you look into the history of Scotland’s weather and climate, we have lived through a remarkably stable period of weather in recent decades. Professor Alastair Dawson’s book, So Foul and Fair a Day: A History of Scotland’s Weather and Climate, makes fairly gruesome reading, with a litany of storms and extreme cold spells followed by famine. No wonder we Scots are thought of as a dour lot!”

McLure points out that the Met Office has a good explanation of the end-of-year cold spell, with the complex La Niña phenomenon being seen as significant. (La Niña is the counterpart of the better-known el Niño, and results from sustained lower-than-average sea-surface temperatures in the central Pacific. Its effects can be felt worldwide, and it appears to have been a factor in the recent extreme weather in Australia.)

“What I wonder,” McLure says, “is why the weather has returned to a more mobile pattern where we get the mild air off the Atlantic. Has la Niña faded, or have other factors such as sea-ice extent, sea-surface temperatures etc reimposed their influence? Maybe we’ll see a return to colder weather later on. Certainly last year saw a final fling of winter in March.”

In terms of the more localised effects, experienced mountain guide Andy Nisbet suggested in early December that he was “torn between thinking this will be the coldest winter since 1947 (or even colder), or merely cold until some time in January.”

He now sees the latter as much the more likely. “The pattern is similar to 1982,” Nisbet says, “following a very cold autumn 1981 and early January 1982. Not that the winter ended in January, just that only the higher cliffs stayed in good condition. And with plenty of snow in the high Cairngorms at present, there’s no need to feel despondent.

“Atlantic air does seem established, and the Scandinavian high only an optimistic dream. So that’s my prediction: milder than average now, but places like Braeriach and the Northern Cairngorms still good.

“In February 1982, I climbed Ebony Chimney in Coire Bhrochain of Braeriach, one of the best routes I’ve done. Plenty of snow, but also several gentle thaws producing loads of ice which made this deep chimney climb memorable.”

Then there is the skiing. It’s been a great first half to the season, both at the commercial centres and for touring in the forests and on the quieter hills – but what of the lead-up to Easter and beyond? Helen Rennie – one of The Caledonian Mercury’s outdoors people of 2010 – was asked for her thoughts.

Even though she describes herself as “the eternal optimist who will ski on postage-stamp sizes of snow,” Rennie is sure there are some good days ahead, despite the general retreat during January.

“Certainly at Cairngorm the base on the upper part of the mountain has been there since November,” she says. “It has undergone many freeze-thaw cycles and been has repeatedly packed down by the piste machines and skiers, so should be solid enough to withstand some mild weather.

“I’ve kept a log of the days I’ve skied since 1996 when I bought my first season ticket after having my children, as they were both at secondary school then so I had more opportunities to ski. The patterns show that February is usually as good as or better than January, the exceptions being 2001 and 2004. March has always had more ski days that January or February, while April has had more ski days than January apart from 2005.

Rennie mainly skis at Cairngorm. “As for the other resorts,” she says, “I don’t feel quite so confident to predict the future. However, from experience, Nevis Range usually skis well in March and April, as does Glencoe. Glenshee, like Cairngorm, has had an excellent start and the base should be compacted – but it tends to have a shorter season.”

She has put together a five-minute YouTube film of the skiing during 2010 (see end of article). “It certainly brings home what fantastic cover we had over the year,” she says.

For now, though, we’re back into a stormy, unstable flow (a gust of 131mph was recorded on Aonach Mor at 5pm yesterday), with fresh snow being laid down on the middle-to-upper altitudes, but with no clarity as yet as to whether this will quickly be washed away/blown off, or whether some cool-weather stability will create a genuinely wintry February.

At present, the Met Office 30-day prediction doesn’t look promising – talk of settled weather from the middle of the coming week, but also “mild”, “southerly flow”, and “above average temperatures”.

As ever, it remains to be seen. This has certainly been a strange and memorable sequence of seasons, whatever now happens. One remarkable statistic about 2010 – a year that saw two serious winters within one cycle of the calendar – was that five of the 12 months saw temperatures drop to at least minus 18C somewhere in the UK.

That doesn’t happen very often – not since at least the 19th century, it is believed.

The UK shrouded in snow. <em>Picture: NEODAAS/University of Dundee</em>

The UK shrouded in snow. Picture: NEODAAS/University of Dundee

There is no such thing as a standard Scottish winter – but, if there is something approaching a traditional format, one seen more often than others, it is roughly as follows.

First comes wild-and-mild stormy weather in the couple of months before the festive season, but with not much snow apart from on the really high ground, 1,000 metres-plus. Occasional ice and mixed (or messy, or thin, or however you want to label it) conditions on medium-sized hills, and nothing much more serious than overnight frost at lower levels.

January brings the main snow-dumps, with the third week of the month tending to be seen as the critical stretch. Then February settles down into lovely anticyclonic weather, the lower ground starts to feel almost springlike, while the hills – now with a substantial base of January snow – go through freeze-thaw cycles such that everyone is happy and there are great on-hill conditions for walkers, climbers and skiers right through until after the clocks change.

That’s the template, sort of. But by pretty much any assessment, whatever it is we’ve been having this time around, it’s very much not that.

There has been a lopsidedness to proceedings. Late November until early January saw plenty of snow at all levels and disruptively low temperatures. Then the bulk of January was mild and placid, with a retreat of the snowline rather than a bulking-up of the snowpack. And now, the current wave of gales and stormy mayhem notwithstanding, it looks like we could end up viewing this as a wrong-way-round winter, a curiosity rather than a classic.

Or will we? At the start of December, The Caledonian Mercury took soundings from a couple of well-informed people as to how they saw the weather and outdoor-activity prospects over the coming weeks. Now seems a good time to go back and ask for a reassessment.

“It looks like we will be back into a spell of wet, windy and relatively mild weather for the next month or so,” says Alison McLure – former BBC weather reporter, now the national officer for Scotland with the Institute of Physics. “I suppose that will be a relief for the general population, but I miss the stunning clear blue days with crisp snow on the ground.

“I was surprised at how quickly the snow melted from the hills, although hopefully the higher climbing routes will stay in good condition. It feels like we are back to the more ‘normal’ winters of the last 20 years or so. However, if you look into the history of Scotland’s weather and climate, we have lived through a remarkably stable period of weather in recent decades. Professor Alastair Dawson’s book, So Foul and Fair a Day: A History of Scotland’s Weather and Climate, makes fairly gruesome reading, with a litany of storms and extreme cold spells followed by famine. No wonder we Scots are thought of as a dour lot!”

McLure points out that the Met Office has a good explanation of the end-of-year cold spell, with the complex La Niña phenomenon being seen as significant. (La Niña is the counterpart of the better-known el Niño, and results from sustained lower-than-average sea-surface temperatures in the central Pacific. Its effects can be felt worldwide, and it appears to have been a factor in the recent extreme weather in Australia.)

“What I wonder,” McLure says, “is why the weather has returned to a more mobile pattern where we get the mild air off the Atlantic. Has la Niña faded, or have other factors such as sea-ice extent, sea-surface temperatures etc reimposed their influence? Maybe we’ll see a return to colder weather later on. Certainly last year saw a final fling of winter in March.”

In terms of the more localised effects, experienced mountain guide Andy Nisbet suggested in early December that he was “torn between thinking this will be the coldest winter since 1947 (or even colder), or merely cold until some time in January.”

He now sees the latter as much the more likely. “The pattern is similar to 1982,” Nisbet says, “following a very cold autumn 1981 and early January 1982. Not that the winter ended in January, just that only the higher cliffs stayed in good condition. And with plenty of snow in the high Cairngorms at present, there’s no need to feel despondent.

“Atlantic air does seem established, and the Scandinavian high only an optimistic dream. So that’s my prediction: milder than average now, but places like Braeriach and the Northern Cairngorms still good.

“In February 1982, I climbed Ebony Chimney in Coire Bhrochain of Braeriach, one of the best routes I’ve done. Plenty of snow, but also several gentle thaws producing loads of ice which made this deep chimney climb memorable.”

Then there is the skiing. It’s been a great first half to the season, both at the commercial centres and for touring in the forests and on the quieter hills – but what of the lead-up to Easter and beyond? Helen Rennie – one of The Caledonian Mercury’s outdoors people of 2010 – was asked for her thoughts.

Even though she describes herself as “the eternal optimist who will ski on postage-stamp sizes of snow,” Rennie is sure there are some good days ahead, despite the general retreat during January.

“Certainly at Cairngorm the base on the upper part of the mountain has been there since November,” she says. “It has undergone many freeze-thaw cycles and been has repeatedly packed down by the piste machines and skiers, so should be solid enough to withstand some mild weather.

“I’ve kept a log of the days I’ve skied since 1996 when I bought my first season ticket after having my children, as they were both at secondary school then so I had more opportunities to ski. The patterns show that February is usually as good as or better than January, the exceptions being 2001 and 2004. March has always had more ski days that January or February, while April has had more ski days than January apart from 2005.

Rennie mainly skis at Cairngorm. “As for the other resorts,” she says, “I don’t feel quite so confident to predict the future. However, from experience, Nevis Range usually skis well in March and April, as does Glencoe. Glenshee, like Cairngorm, has had an excellent start and the base should be compacted – but it tends to have a shorter season.”

She has put together a five-minute YouTube film of the skiing during 2010 (see end of article). “It certainly brings home what fantastic cover we had over the year,” she says.

For now, though, we’re back into a stormy, unstable flow (a gust of 131mph was recorded on Aonach Mor at 5pm yesterday), with fresh snow being laid down on the middle-to-upper altitudes, but with no clarity as yet as to whether this will quickly be washed away/blown off, or whether some cool-weather stability will create a genuinely wintry February.

At present, the Met Office 30-day prediction doesn’t look promising – talk of settled weather from the middle of the coming week, but also “mild”, “southerly flow”, and “above average temperatures”.

As ever, it remains to be seen. This has certainly been a strange and memorable sequence of seasons, whatever now happens. One remarkable statistic about 2010 – a year that saw two serious winters within one cycle of the calendar – was that five of the 12 months saw temperatures drop to at least minus 18C somewhere in the UK.

That doesn’t happen very often – not since at least the 19th century, it is believed.