Anyone scrambling the craggy slopes of Ben Nevis in the Scottish highlands this summer may have stumbled across an unexpectedly beautiful sight. Though the days were relatively mild, snow still covered some areas of the mountain, forming glacier-like patches. Where water had carved its way through, there were snow tunnels that, from within, appeared to glow with a blue hue.
We may not think of the UK as a particularly snowy place, but in fact snow has disappeared completely from the country only six times in recorded history (around 300 years), during the years 1933, 1959, 1996, 2003, 2006 and 2017. While England and Wales shed all their snow in the summer, some areas in Scotland usually cling on all the way through the season, until they are eventually replenished in winter. ‘Every year after the full melt in 2006 there was enough snow to keep burying the previous snow. So in the year 2017 you could stand on snow in Britain that had been there for 11 years,’ says Chris Speight.
It is because of people like Chris that we are aware of which years are particularly snowy, and which years see snow disappear in its totality. A professional geographer and environmental consultant in his day job, he also volunteers for a group called Snow Patches in Scotland (there is also a Snow Patches in England and Wales), to hunt for summer snow. In one form or another the group has been collecting these records for decades.
Systematic monitoring of snow patches began in the 1970s under the efforts of the well-known ecologist Adam Watson, a long-standing environmental campaigner and ski-mountaineer with an appropriately snowy white beard, who died in 2018.
Watson would start his surveys on 1 July each year, repeating the count at the beginning of successive months until the earliest lasting snowfall of the new winter, which usually came in October. Today, group leader Iain Cameron follows a similar process. He, along with Blair Fyffe, also produce bi-annual reports for the Royal Meteorological Society’s Weather journal, contributing to a unique record of climate influences across Britain’s highest mountains. This year, along with the evidence provided by on-foot volunteers, they were able to monitor Scotland’s snow using a light aircraft.
‘The main factor is obviously how much snow accumulation there is in winter. And then the temperatures and rainfall in spring and summer have a big influence,’ says Chris, who recently returned from a snow-finding expedition on Ben Nevis. ‘So this winter wasn’t a particularly good year, up until storm Ciara.’
The storm, coupled with one of the driest springs on record means that 2020 has been a good year for snow, though this bucks the trend of the previous three years which amounted to the lowest three-yearly total since comprehensive records began. While 2017 saw snow disappear completely, only one patch survived until the following winter in 2018 and 2019, at Aonach Beag and Braeriach’s Garbh Choire Mòr respectively.
The snow surveys were never intended to be a record of climate change, but such a comprehensive and long-lasting data set is inevitably useful for climate scientists. The overall trend, says Chris Speight, is of a decrease in snow. ‘If you look at the overall trend from 1930 onwards, there’s a general decrease in t-he number and longevity of snow patches.’ He emphasises the importance of long-term records for this kind of monitoring. ‘If you look at one, two, five or ten years the data doesn’t stack up. But once you look at decades at a time, you can’t really argue with it.’
But for Scotland’s snow hunters, this remains a useful by-product. For them it is all about the beauty of snow, a substance that never fails to engender excitement, that begs to be touched and handled, and which renders the landscape a very different place. As the pioneer Adam Watson said, in an interview in 2009: ‘I lived in the centre of this village and it was normally a noisy, busy place, but the snow deadened the sound. There was snow on every tree, every pavement, covering all the roads and so on. It had become a quiet world.’