Glacier at Kebnekaise’s summit has shrunk amid soaring Arctic temperatures, say scientists
“This is quite a symbol,” said Gunhild Ninis Rosqvist, a Stockholm University geography professor who has been measuring the glacier annually for several years. “A very obvious, very clear signal to everyone in Sweden that things are changing.”
In the far north of Sweden, about 95 miles (150km) inside the Arctic circle, Kebnekaise has two peaks: a southern, glacier-covered summit accessible to suitably equipped hikers, and a northern neighbour that is free of ice but reserved for experienced mountaineers.
Since they were first measured in 1880, the southern peak has been the higher. But when Ninis Rosqvist and her team took this year’s measurements, at the end of the summer melt on 3 September, the northern peak was 1.2 metres higher at 2,096.8 metres.
“We suspected this was probably the case last year,” Ninis Rosqvist told the Guardian from the Tarfala research station at the foot of the massif. “But unfortunately our measurements were not precise enough. Now we can say with certainty: we are accurate to within a couple of centimetres.”
The scientist said the height of Kebnekaise’s southern peak was the lowest on record: 24 metres less than in the 1960s. “Almost all the shrinkage has been in past two decades, when the glacier has lost an average of one metre a year,” she said.
Since the glacier was likely to expand again with winter snow and ice, the southern peak could briefly recover its ranking, Ninis Rosqvist said. “It will keep changing for a while,” she said. “But the trend is now firmly established, and very clear.”
Sweden recorded its hottest ever months of May and July in 2018, with temperatures soaring to more than 10C above normal. With wildfires burning across the Arctic, the Kebnekaise glacier shrank by almost four metres.
Although this July was not as hot after an unusually cool start to the month, the village of Markusvinsa in the far north of the country recorded 34.8C on 26 July – the highest temperature ever recorded north of the Arctic circle in Sweden.
Ninis Rosqvist said small glaciers such as that on Kebnekaise’s southern peak were particularly badly affected by warm summers. It was mainly cool summers that allowed glaciers to grow, rather than particularly harsh winters, she said. But the past two Scandinavian summers had caused the snow and ice to melt away very fast. “You can see it at the top, where it’s most exposed to the sun. It really looks different. It gets slippery up there; you can see the meltwater running off.”
The news may have been expected, but the official downgrading of the southern peak was still “emotionally quite something”, Ninis Rosqvist said. “The mountains are changing so fast – higher temperatures, less snow, winter rain.”
The glacier on Kebnekaise’s southern peak was “iconic – a symbol for all the glaciers in Sweden”, she said, adding: “But you know, we don’t need any more symbols. We don’t need to pile up more evidence. We can see the climate changing before our eyes up here, and we need to do something about it.”
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