By Stephen Beech
A record number of glaciers will disappear from the Alps over the next decade, warns new research.
Scientists have for the first time calculated how many glaciers worldwide are likely to remain until the end of the 21st Century.
Depending on how sharply the planet warms, the ground-breaking study shows that in a scenario with a global temperature rise of +4.0⯰ Celsius, only about 18,000 of more than 200,000 glaciers worldwide would remain.
But an increase of +1.5⯰C would see around 100,000 glaciers survive.
The researchers coined the term “Peak Glacier Extinction” – the point when annual glacier loss hits its maximum.
At +1.5⯰C it occurs around the year 2041 with 2,000 glaciers lost; at +4⯰C it shifts to 2055 and rises to 4,000.
Glaciers are currently melting worldwide and, in some regions, they could even disappear completely.
Looking at the number of glaciers disappearing, scientists say the Alps could reach their peak loss rate as early as 2033 to 2041.
Depending on how sharply the planet warms, the period may mark a time when more glaciers vanish than ever before.
Worldwide, the peak glacier loss rate will occur around 10 years later and could rise from 2,000 to 4,000 glaciers lost each year.
Scientists say the outlook for the Alps is stark.
If current climate policies steer the world towards a temperature rise of +2.7⯰C, scientists say only about 110 glaciers would remain in Central Europe by 2100 – a mere 3% of today’s total.
At +4⯰C, that number would plunge to around 20.
Even medium-sized glaciers – such as the Rhône Glacier – would shrink to tiny remnants of ice or disappear completely.
Under that scenario, scientists say even the mighty Aletsch Glacier would fragment into several smaller parts.
Research shows that between 1973 and 2016, more than 1,000 glaciers vanished in Switzerland alone.
For the new study, an international team, led by researchers from ETH Zurich University in Switzerland, calculated how many glaciers worldwide disappear each year.
Study lead author Dr. Lander Van Tricht, of ETH Zurich, said: “For the first time, we’ve put years on when every single glacier on Earth will disappear.”
Unlike previous studies, which mainly focused on global ice mass and surface area loss, the new research shifts the spotlight to the number of disappearing glaciers, their regions, and the timeline of their disappearance.
The findings, published in the journal Nature Climate Change, reveal that regions with many small glaciers at lower elevations or near the equator are particularly vulnerable – including the Alps, the Caucasus, the Rocky Mountains, as well as parts of the Andes and African mountain ranges that lie in low latitudes.
Dr. Van Tricht said: “In these regions, more than half of all glaciers are expected to vanish within the next 10 to 20 years.”
For the Alps, the team found that with a +1.5⯰C rise, 12% of glaciers would remain by 2100 – around 430 out of about 3,000 in 2025; at +2.0⯰C, around 8% would survive – and at +4⯰C, just 1%, or 20 glaciers, would survive.
In the Rocky Mountains, around 4,400 glaciers would endure under the 1.5⯰C scenario, according to the study, about 25% of today’s roughly 18,000 glaciers.
At +4⯰C, only about 101 would remain, a 99% loss.
In the Andes and Central Asia, about 43% would survive at 1.5⯰C, but at +4⯰C, the numbers plummet.
In the Andes, only around 950 glaciers would remain, a 94% loss.
In a scenario with a global temperature rise of +4.0⯰C only about 18,000 glaciers would remain worldwide, whereas at +1.5°C there would be around 100,000, according to the study.
The report also shows that there is no region left where glaciers’ numbers are not declining.
Under a +1.5⯰C rise in global warming, as envisaged by the Paris Agreement, Peak Glacier Extinction would occur around 2041, when roughly 2,000 glaciers vanish in just one year.
At +4⯰C, the peak shifts to about 2055 – but climbs to around 4,000 glaciers.
The researchers say the reason the peak comes later in warmer conditions is because, not only do small glaciers melt completely, but larger glaciers vanish as well.
Study co-author Professor Daniel Farinotti, also of ETH Zurich, said: “The results underline how urgently ambitious climate action is needed.”
Dr. Van Tricht said: “The melting of a small glacier hardly contributes to rising seas.
“But when a glacier disappears completely, it can severely impact tourism in a valley.”
He added: “Every glacier is tied to a place, a story and people who feel its loss.
“That’s why we work both to protect the glaciers that remain and to keep alive the memory of those that are gone.”
