Recent Retreat of Tropical Andean Glaciers Unprecedented in 11,700 Years

Science, 1 August 2024

The current rate of glacier ice loss in the tropical Andes is unprecedented in at least the last 11,700 years, according to a new study. Researchers measured rare nuclides (isotopes) created when high-energy cosmic rays interact with rocks exposed to sunlight at the margins of glaciers in the tropical Andes. Their results showed that these locations were never exposed during the Holocene – the last 11,700 years – meaning that they remained covered by ice throughout this time period. These tropical glaciers are therefore smaller now than they have been in at least 11,700 years, signaling that substantial impacts on ecosystems and communities that rely on glaciers for freshwater have occurred even at today’s level of warming.

Full paper: https://www.science.org/doi/10.1126/science.adg7546