For nearly 12,000 years, the rivers of ice that cling to mountains from Alaska to New Zealand have stood as reminders of an era when vast swathes of the planet were encased in frozen water.
Even at the equator, where the land thrusts high enough, ice has stayed in place, defying the intense tropical sun. Yet decades of man-made climate change mean that thousands of glaciers across the globe now face extinction.
“There is a lag [between warming and melting], so even if from tomorrow there were no more CO2 emissions worldwide, even then glaciers in the Alps would lose about 50 per cent of their mass,” explains Dr Matthias Huss. “They’re too big for the present climate.”
Dr Huss is a glaciologist from ETH Zurich, one of Switzerland’s top universities and leads the country’s glacier monitoring body Glamos. From his vantage point at the heart of the Alps, he is witnessing the rapid deterioration of Europe’s glaciers at first-hand.
Last year was a record for ice loss in Switzerland, with a lack of snowfall in winter to provide insulation for the ice and repeated heatwaves in the summer causing Swiss glaciers to lose six per cent of their mass or around three cubic kilometres of ice.
That figure smashed the previous record for glacier melt from 2003. Until last year, a two per cent loss would have been considered extreme.
This year, says Dr Hauss, hasn’t been much better “This has all happened again, after a record year in 2022. The zero-degree line rose to more than 5000 meters, which is the highest ever that has been observed,” he said, referring to the altitude at which the temperature hits freezing.
The consequence is that smaller glaciers, which lack the mass to survive, are already doomed. Crucially, ice lost now is unlikely to be recovered, meaning that each year of dramatic melting simply accelerates the Alps towards a future with little or no ice.
“In the short, medium-term future nothing can be changed, but we have the option to change the long-term future. In the scenario with no CO2 reduction, all ice would disappear by the end of the century.
“But if we implement the Paris agreement we could save around a third of the ice in the Alps.”
Since 1850, the last peak in ice mass, the Alps have lost two-thirds of their ice already. What might remain will therefore, in the best case, be just a third of a third – little more than 10 per cent of their 19th century glacial boom.
There have, points out Dr Claus-Dieter Hillenbrand at the British Antarctic Survey (BAS), always been fluctuations in climate that can cause glaciers to shrink. Two factors make this period different, however. One, climate change is making the extremes even more extreme. And two, the background temperature levels are that much higher that glaciers cannot recover in the periods between extremes.
According to Dr Huss, average temperatures would need to fall by two to three degrees Celsius for glaciers to start regaining mass. Given that best-case scenarios involve keeping warming at 1.5°C, that won’t happen in our lifetimes.
Such is the increase in temperatures that the so-called equilibrium line altitude, at which ice mass is neither shrinks nor grows, has shifted uphill by around 200 metres in the past few decades to around 3,000m. By 2100 it could be 4,000m. Mont Blanc, the highest peak in the Alps is 4,808m.
For a glimpse of the future, says Dr Huss, Europeans need only look to the Pyrenees, which top out at 3,404 metres. “They used to be glaciarised… but nowadays the region is almost ice free. What’s left is on the way to extinction.”
While Europe can, with serious effort to address climate change, cling on to some remnants of its icy inheritance, at the Tropics it is already game over.
The higher temperatures at the equator mean that mountain aeries simply aren’t high enough for ice to cling on. Last week, geophysicists in Indonesia announced that the arrival of an El Niño weather pattern was likely to accelerate the disappearance of the country’s Eternity Glaciers, which could vanish by 2026
In Venezuela, the country’s last river of ice, the Humboldt Glacier at 4,905m, has been reduced to just 2.5 acres and will soon be gone. According to Unesco, Africa will lose all of its glaciers, including what little ice is left on Mount Kilimanjaro.
The consequences for local people when those glaciers disappear can be severe. In Asia, 250 million people directly rely on the melt waters of the Himalayas and Hindu Kush with a further 1.6 billion reliant on rivers at least partly fed by mountain ice.
Even in wealthier parts of the world, the loss of glaciers is a problem. “Glaciers fill the gap during dry periods with meltwater, this is very important, but we will lose this role within the next decade,” Dr Huss says. “In Switzerland, we get 50 per cent of our electricity from hydropower and all of these are fed by glacial meltwater.”
While the localised impact of glacier gloss will be enormous, when it comes to the global scale scientists’ biggest fears lie elsewhere.
In Antarctica and Greenland, there is enough frozen water locked up to last centuries, perhaps millennia even, even with runaway climate change. But that also means that the melting of this polar ice could have severe consequences.
Were the whole of the West Antarctic ice sheet to melt, it would result in three metres of global sea level rises. The rush of cold, dense freshwater would also likely severely disrupt ocean currents, sending global weather patterns haywire.
Even without such dramatic scenarios, Antarctica’s glaciers are so enormous that even individual rivers of ice can have a global footprint.
The Thwaites Glacier in west Antarctica is thought to have contributed 4 per cent of the recent rise in global sea levels. More importantly, it acts as a keystone to the West Antarctic ice sheet. If, as scientists at BAS fear, Thwaites reaches a tipping point and breaks up, the rest of the ice sheet could follow.
Dr Hillenbrand is part of the team at BAS monitoring Thwaites in the hope of ascertaining whether that tipping point really is approaching, or indeed, has already been crossed.
“The basic question is if what we are seeing is reversible or not,” he says.
As much as scientists can study and model the ice, however, the more humanity messes with the global climate, the more it has the chance to surprise and shock them, throwing their expectations out of the window.
Right now, it is deepest midwinter in Antarctica and its sea ice should be reaching its maximum extent. Instead, there is less ice than scientists have ever previously documented. Not only is that a sign of a climate in distress, but it exposes the Thwaites and other glaciers to further erosion from storms and melting from seawater.
Dr Hillenbrand, who has been visiting the Antarctic since 1994, is just back from an expedition to the Amundsen Sea, off West Antarctica. “It was quite scary, the fact that we didn’t encounter any sea ice at all. Quite worrying.”
For nearly 12,000 years, the rivers of ice that cling to mountains from Alaska to New Zealand have stood as reminders of an era when vast swathes of the planet were encased in frozen water.Even at the equator, where the land thrusts high enough, ice has stayed in place, defying the intense tropical sun. Yet decades of man-made climate change mean that thousands of glaciers across the globe now face extinction.“There is a lag [between warming and melting], so even if from tomorrow there were no more CO2 emissions worldwide, even then glaciers in the Alps would lose about 50…
‘All ice could disappear’: Europe’s heatwaves threaten to wipe out … – inews
Source: Assent.Environmental