The retreat of the tropics glaciers across the Andes is unprecedented in the history of human civilization, finds a study published in the main scientific journal. Science.
Measurements of rocks exposed by melting ice show that Andean glaciers are at their lowest levels since the end of the most recent ice age 11,700 years ago.
The researchers even say they were surprised by the findings: “We thought something like this was still a few decades away,” said Andrew Gorin of Boston College, who led the study.
“It’s happening faster than even we who study it thought.”
As Gorin said, his team had a hard time believing the results until they were confirmed by analyzing more samples.
The study comes just months after Venezuela, one of the Andean countries, was recognized as the first country in the world is losing all its glaciers due to climate change.
The findings in the Andes, home to 99% of the world’s tropical glaciers, offer ominous pictures of the future of glaciers across the rest of the planet, the researchers said.
The Cordillera Blanca mountain range in the Peruvian Andes (Reuters
Andean glaciers “are like the canary in the mine”, commented Gorin. “The same thing will happen everywhere soon, maybe sooner than we thought.”
Until now, scientists believed that the world’s glaciers reached their minimum levels in the early to middle Holocene, the geological era that began with the end of the most recent ice age.
The study in Science reverses this picture.
The researchers examined rock samples recently exposed around four glaciers, and measured the levels of two rare radioisotopes, beryllium-10 and carbon-14, which form when the rocks are bombarded with cosmic radiation from space.
Levels of the two isotopes were close to zero, meaning that the rocks remained ice-covered until recently.
“Glaciers are very sensitive to the climate system,” said Sean Marcotte of the University of Wisconsin-Madison, a member of the research team.
“Looking at them you can imagine what we might see in the future in other regions like the western United States, a completely ice-free scenario.”
The study comes as high temperature records are being broken around the world due to climate change.
It was June this year the hottest ever recorded and available data indicate that in 2024 may exceed 2023 as the hottest year on record, which it was perhaps the hottest in 100,000 years.