Thursday, September 28, 2023

Two 'catastrophic' years melt away 10% of Swiss glacier volume: study

Nina Larson with Alexandre Grosbois
Thu, September 28, 2023 

The study showed a dramatic retreat of Swiss glaciers and warned the situation would only get worse (Fabrice COFFRINI)

Two consecutive years of extreme warming in the Alps have obliterated 10 percent of Swiss glacier volume -- the same amount lost in the three decades prior to 1990, a report revealed Thursday.

Amid growing concerns over the dire toll of climate change, the study by the Cryospheric Commission (CC) of the Swiss Academy of Sciences showed a dramatic glacial retreat, and warned the situation would only get worse.

"Swiss glaciers are melting at a rapidly increasing rate," it said in a statement.

2022 marked the worst year on record for glacier melt in the Swiss Alps, with six percent of the total ice volume lost.


The glaciers have not fared much better this year, the CC report showed, with another four percent of ice volume destroyed, "representing the second largest decline since measurements began".

"The acceleration is dramatic, with as much ice being lost in only two years as was the case between 1960 and 1990," it said.

The result of two consecutive extreme years had been collapsing glacier tongues and some smaller glaciers vanishing all together.

"All glaciers melted a lot," Matthias Huss, head of Glacier Monitoring in Switzerland (GLAMOS), told AFP.

"But for the small glaciers, (the) melting is especially dramatic because these small glaciers are really disappearing right now."

- 'Dead ice' -


GLAMOS, which monitors 176 of Switzerland's some 1,400 glaciers, recently halted measurements at the St. Annafirn glacier in the central Swiss canton of Uri since it had all but disappeared.

"We just had some dead ice left," Huss lamented.

The massive glacier loss seen in Switzerland was linked in large part to a winter with very low snow volumes, as well as soaring summer temperatures.

"It's a combination of climate change that makes such extreme events more likely, and the very bad combination of meteorological extremes," Huss explained.

"If we continue at this rate... we will see every year such bad years."

Scientists have already warned that the Swiss glaciers could all but disappear by the end of the century without more action to rein in global warming.

"We have seen such strong climate changes in the last years that it's really possible to imagine this country without any glaciers," Huss said.

- 'Stabilise the climate' -

He stressed the need to "stabilise the climate by bringing the CO2 emissions to zero as soon as possible".

But Huss acknowledged that even if the world managed to meet the Paris targets of limiting global warming to 1.5 degrees Celsius above pre-industrial levels, only around a third of glacier volume in Switzerland would be saved.

That means that "all the small glaciers will be gone anyway, and the big glaciers will be much smaller", he said, but stressed that at least "there will be some ice in the highest regions of the Alps and some glaciers that we can show to our grandchildren."

This year's melt impacted glaciers across Switzerland, with those in the south and the east of the country particularly hard-hit.

The average ice thickness loss there was up to three metres (9.8 feet) and was "considerably higher than the values recorded in the hot summer of 2003", the researchers said.

The study showed that even some glaciers above 3,200 metres (10,500 feet), which until recently had "preserved their equilibrium", had seen several metres of ice melt away.

The year was marked by barely any precipitation at all over the 2022-23 winter months, meaning far less snow cover than usual, followed by the third-warmest summer in the Alps since measurements began.

It got so warm that at one stage, the freezing point above the mountain range rose to 5,298 metres (17,381 feet) -- way above the highest peaks and beating by far the zero-degree line record.

As thaw accelerates, Swiss glaciers have lost 10% of their volume in the past 2 years, experts say

JAMEY KEATEN
Updated Thu, September 28, 2023 






- Team members of ETH (Swiss Federal Institute of Technology) glaciologist and head of the Swiss measurement network Glamos, Matthias Huss, arrive at the Rhone Glacier that is partially covered near Goms, Switzerland, June 16, 2023.
 (AP Photo/Matthias Schrader, File)

GENEVA (AP) — A Swiss Academy of Sciences panel is reporting a dramatic acceleration of glacier melt in the Alpine country, which has lost 10% of its ice volume in just two years after high summer heat and low snow volumes in winter.

Switzerland — home to the most glaciers of any country in Europe — has seen 4% of its total glacier volume disappear in 2023, the second-biggest decline in a single year on top of a 6% drop in 2022, the biggest thaw since measurements began, the academy’s commission for cryosphere observation said.

Experts at the GLAMOS glacier monitoring center have been on the lookout for a possible extreme melt this year amid early warning signs about the country's estimated 1,400 glaciers, a number that is now dwindling.

“The acceleration is dramatic, with as much ice being lost in only two years as was the case between 1960 and 1990,” the academy said. “The two extreme consecutive years have led to glacier tongues collapsing and the disappearance of many smaller glaciers.”

Matthias Huss, head of GLAMOS, which participated in the research, said in an interview that Switzerland has already lost up to 1,000 small glaciers, and that “now we are starting to lose also bigger and more important glaciers.”

“Glaciers are the ambassadors of climate change. They make it very clear what is happening out there because they respond in a very sensitive way to warming temperatures,” he said. “The study underlines once again that there is big urgency to act now if you want to stabilize (the) climate, and if you want to save at least some of the glaciers.”

The team said the “massive ice loss" stemmed from a winter with very low volumes of snow — which falls on top of glaciers and protects them from exposure to direct sunlight — and high summer temperatures.

All of Switzerland — where the Alps cut a swath through most of the southern and central parts of the country — was affected, and glaciers in the southern and eastern regions melted almost as fast as in 2022's record thaw.

“Melting of several meters was measured in southern Valais (region) and the Engadin valley at a level above 3,200 meters (10,500 feet), an altitude at which glaciers had until recently preserved their equilibrium,” the team said.

The average loss of ice thickness was up to 3 meters (10 feet) in places such as the Gries Glacier in Valais, the Basòdino Glacier in the southern canton, or region, of Ticino, and the Vadret Pers glacier system in eastern Graubuenden.

The situation in some parts of the central Bernese Oberland and the Valais was less dramatic — such as for the Aletsch Glacier in Valais and Plaine Morte Glacier in the canton of Bern, because they enjoyed more winter snowfall. But even in such areas, “a loss of over 2 meters of the average ice thickness is extremely high,” the team said.

Snow depths measured in the first half of February were generally higher than in the winters of 1964, 1990 or 2007, which were also characterized by low snowfalls, the team said. But snow levels sank to a new record low in the second half of the month of February, reaching only about 30% of the long-term average.

Over half of automated monitoring stations above 2,000 meters that have been in place for at least a quarter-century tallied record-low levels of snow at the time.

After that, an extremely warm June caused snow to melt two to four weeks earlier than usual, and mid-summer snowfalls melted very quickly, the team said.

Swiss meteorologists reported in August that the zero-degree Celsius level — the altitude where water freezes — had risen to its highest level ever recorded, at nearly 5,300 meters (17,400 feet), which means that all the Swiss Alpine peaks faced temperatures above freezing.

Swiss glaciers get 10% smaller in two years

Imogen Foulkes - BBC News, Geneva
Thu, September 28, 2023 

The radiantly blue glacial lakes on the Findel Glacier were covered by dozens of metres of ice a decade ago

Switzerland's glaciers have lost a further 4% of their volume this year - the second biggest loss ever - after last year's record melt of 6%.

The statistics come in the annual report of the Swiss Glacier Monitoring Network (Glamos), whose team of researchers have been monitoring 176 of Switzerland's 1,400 glaciers for years.

They warn it may now be too late to save many of the alpine ice fields, even if climate targets are met.

"It's terrible," said the Glamos chief.

In just two years, Switzerland's glaciers have lost 10% of their total volume - as much as they lost in the three decades between 1960 and 1990.

Glaciologists measuring the ice take no comfort in the fact that this year's melt is slightly smaller than last year's record.

"It was still the second most negative year since measurements started," Matthias Huss, the head of Glamos, told the BBC. "It's terrible to see that this extreme of last year is just repeating."

The researchers say the loss is due to consecutive very warm summers, and last winter's very low snowfall. If these weather patterns continue, they say, the thaw will only accelerate.

Some of Switzerland's smaller glaciers have already disappeared.

This year the researchers stopped monitoring the St Annafirn glacier because there was no ice left worth measuring.

Others are shrinking so fast it is unlikely they can be saved, even if global temperatures are kept within the Paris target of a 1.5C rise.

Without a dramatic reduction in greenhouse gases linked to global warming, glacier experts warn that even the bigger glaciers like the Aletsch, whose ice now is 800m (2,624 ft) thick in parts, could disappear within a generation.

"Every time I come back to these sites that I have monitored for many years, it's different,' said Mr Huss. "The ice is smaller, thinner, more grey. It's very sad."

But losing the glaciers is about more than losing a stunning view.

The ice, which traditionally builds up in winter and melts slowly in summer, provides fresh water vital to Europe's rivers, to irrigate Europe's crops or to cool its nuclear power stations.

Last year and again this year, shipping on the river Rhine, a key waterway for Europe's freight, had to be restricted because the water had become too shallow.

During the record heat of 2022, fish were removed from Swiss rivers and stored in tanks, because the river water itself had become too warm and too scarce for the fish to survive.

"Glaciers are very important for communicating climate change, because they are so visible," said Mr Huss.

"If there is no climate mitigation, we are going to lose all the glaciers in the alps by 2100."

Switzerland’s glaciers lose ‘mind-blowing’ volume of ice in just two years

Laura Paddison, CNN
Thu, September 28, 2023 

Glaciers in Switzerland are shrinking at a “mind-blowing” rate. A total of 10% of their ice volume has disappeared over a period of just two years as a combination of low snowfall and soaring temperatures cause unprecedented melting, according to figures released Thursday.

In 2023, the country’s glaciers lost 4% of their total volume, according to data from the Swiss Commission for Cryosphere Observation of the Swiss Academy of Sciences. This level melting is second only to the record set in 2022, when 6% of glaciers were destroyed.

To put this into perspective, Swiss glaciers have lost as much ice over this two-year period as was lost over the three decades between 1960 and 1990.

“The losses we’ve seen in 2022 and 2023 are simply mind-blowing and beyond everything we have experienced so far,” said Matthias Huss, head of the Swiss Glacier Monitoring Network (GLAMOS), an organization that collects and evaluates glacier data and works with the Swiss Academy of Sciences.

“Even though glaciers have constantly and quickly been losing mass for many decades, this is a tremendous acceleration,” he told CNN, adding these extremes “would have been impossible without climate change.”

Ice on the Vadret dal Murtèl glacier melted rapidly even in mid-September at an altitude of 3,100 meters (10,170 feet). - Matthias Huss/GLAMOS

The two extreme years have led to glacier tongues collapsing and many small glaciers in the country disappearing altogether. The St. Annafirn glacier, for example, in the Uri canton in central Switzerland, has shrunk so much that GLAMOS has stopped monitoring it.

Ice loss was even recorded at high altitudes, which usually don’t see such declines. Several meters of ice disappeared in southern Valais and the Engadin valley at altitudes of more than 3,200 meters (10,500 feet), according to GLAMOS.

The losses, which affect glaciers across the country, have come after a winter with very low snow. Snow levels in the second half of February reached a record low, at around 30% of the long-term average.

This was followed by a summer of high temperatures. A very hot and dry June meant snow melted two to four weeks earlier than usual, according to GLAMOS.

In August, a weather balloon launched by the national meteorological service, MétéoSuisse, had to climb 5,298 meters (17,382 feet) before the temperature fell to 0 degrees Celsius (32 Fahrenheit) – marking the highest “zero degree” line since records began.

High temperatures, which continued into September, meant that summer snowfalls melted quickly.


The disappearance of the ice ridge at the Piz Murtèl in Grisons, Switzerland. - Matthias Huss/GLAMOS

The huge glacier melt of the last two years has stark implications. It “means a significant re-shaping of the high-alpine landscape,” Huss said.

It is creating dangerous conditions with unstable rock threatening dangerous rockslides.

Receding glaciers are also leading to grim discoveries. In July, the remains of a German mountain climber who went missing 37 years ago while hiking along a glacier near Switzerland’s famous Matterhorn were recovered.

There are temporary advantages as the water runoff from the glaciers has helped relieve the severity of the drought the country has experienced and fill hydropower reservoirs, said Huss.

“However, this benefit is transient and short-lived,” he added. As they shrink, glaciers are rapidly losing their important role to contribute water when people need it. “This will aggravate water scarcity during heat waves in the near future,” Huss said.

The long-term picture for Switzerland’s glaciers is alarming. “Glaciers in the Alps will continue to massively shrink and retreat to the highest mountain peaks,” said Huss.

In June, Swiss voters agreed a new law to significantly reduce levels of planet-heating pollution, the impetus for which came from climate groups demanding an end to fossil fuels in order to save the glaciers.

But time is running out as climate change accelerates. Recent research found that even if ambitious climate targets are met, up to half of the world’s glaciers could disappear by the end of the century.

Swiss glaciers lose 10% of volume in worst two years on record

Thu, September 28, 2023


Visitors walk in a fleece covered ice cave inside the Rhone glacier in Obergoms

By Cecile Mantovani and Denis Balibouse

ZURICH (Reuters) - Switzerland's glaciers suffered their second worst melt rate this year after record 2022 losses, shrinking their overall volume by 10% in the last two years, monitoring body GLAMOS said on Thursday.

The one-two punch for Swiss glaciers during the country's third hottest summer on record means they lost as much ice in two years as in the three decades before 1990, it said, describing the losses as "catastrophic".

"This year was very problematic for glaciers because there was really little snow in winter, and the summer was very warm," Matthias Huss, who leads Glacier Monitoring Switzerland (GLAMOS), told Reuters.

"The combination of these two factors is the worst that can happen to glaciers."

More than half of the glaciers in the Alps are in Switzerland where temperatures are rising by around twice the global average due to climate change.

This year, low winter snowfall combined with an early start and a late end to the summer melt season dealt the heavy losses, GLAMOS said.

In the peak melt month of August, the Swiss weather service said the elevation at which precipitation freezes hit a new record overnight high, measured at 5,289 meters (17,350 ft), an altitude higher than Mont Blanc's summit. This exceeded last year's record of 5,184 meters.

Pictures posted by Huss on social media during data collection trips in recent weeks showed for the first time on record new lakes forming next to glacier tongues, streams of melt water running through ice caves, and bare rock poking out from thinning ice. In some places, bodies lost long ago have been recovered as ice sheets have shrunk.

"We are really losing the small glaciers," Huss said. "The remnant ice is becoming covered by rocks and debris, regions that have been snow and ice covered over the last decades and centuries are becoming just black slopes that are dangerous because of rockfall."

In some places, GLAMOS had to cease monitoring due to the melt.

"We have closed down one of our monitoring programs on a small glacier in central Switzerland because it just became too dangerous to measure," Huss said. "It became very small and therefore unrepresentative."

Swiss records go back to at least 1960 and as far back as 1914 for some glaciers.

(Writing by Emma Farge; editing by Timothy Gardner)

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