Aug 2, 2024 04:28 AM
https://www.eurekalert.org/news-releases/1053110
INTRO: Rocks recently exposed to the sky after being covered with prehistoric ice show that tropical glaciers have shrunk to their smallest size in more than 11,700 years, revealing the tropics have already warmed past limits last seen earlier in the Holocene age, researchers from Boston College report today in the journal Science.
Scientists have predicted glaciers would melt, or retreat, as temperatures warm in the tropics – those regions bordering the Earth’s equator. But the study’s analysis of rock samples adjacent to four glaciers in the Andes Mountains shows that glacial retreat has happened far faster and already passed an alarming cross-epoch benchmark, said Boston College Associate Professor of Earth and Environmental Sciences Jeremy Shakun
“We have pretty strong evidence that these glaciers are smaller now than they have been any time in the past 11,000 years,” said Shakun, a paleoclimatologist and co-author of the report. “Given that modern glacier retreat is mostly due to rising temperatures – as opposed to less snowfall, or changes in cloud cover – our findings suggest the tropics have already warmed outside their Holocene range and into the Anthropocene.”
In other words, the glaciers may no longer be classified as being of the Holocene interglacial period, a significant epoch that saw the birth of civilization, where the flow of water and sea level dictated where towns and cities formed, and where agricultural and commercial activity emerged. Instead, they may be best classified by an epoch that may be well on its way to spelling their end: the Anthropocene.
The findings signal more of the world’s glaciers are likely retreating far faster than predicted, possibly decades ahead of a grim climatological schedule... (MORE - details, no ads)
INTRO: Rocks recently exposed to the sky after being covered with prehistoric ice show that tropical glaciers have shrunk to their smallest size in more than 11,700 years, revealing the tropics have already warmed past limits last seen earlier in the Holocene age, researchers from Boston College report today in the journal Science.
Scientists have predicted glaciers would melt, or retreat, as temperatures warm in the tropics – those regions bordering the Earth’s equator. But the study’s analysis of rock samples adjacent to four glaciers in the Andes Mountains shows that glacial retreat has happened far faster and already passed an alarming cross-epoch benchmark, said Boston College Associate Professor of Earth and Environmental Sciences Jeremy Shakun
“We have pretty strong evidence that these glaciers are smaller now than they have been any time in the past 11,000 years,” said Shakun, a paleoclimatologist and co-author of the report. “Given that modern glacier retreat is mostly due to rising temperatures – as opposed to less snowfall, or changes in cloud cover – our findings suggest the tropics have already warmed outside their Holocene range and into the Anthropocene.”
In other words, the glaciers may no longer be classified as being of the Holocene interglacial period, a significant epoch that saw the birth of civilization, where the flow of water and sea level dictated where towns and cities formed, and where agricultural and commercial activity emerged. Instead, they may be best classified by an epoch that may be well on its way to spelling their end: the Anthropocene.
The findings signal more of the world’s glaciers are likely retreating far faster than predicted, possibly decades ahead of a grim climatological schedule... (MORE - details, no ads)