2024/08/01 by Andrew L. Gorin, Jeremy D. Shakun, Andrew G. Jones +11 · 1 voice · 3 citations
Earth and Planetary Sciences · Social Sciences · #Cryospheric studies and observations #Geology and Paleoclimatology Research #Pleistocene-Era Hominins and Archaeology
paper · doi:10.1126/science.adg7546
openalex publication_date 2024/08/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/23
Tropical glaciers have retreated over recent decades, but whether the magnitude of this retreat exceeds the bounds of Holocene fluctuations is unclear. We measured cosmogenic beryllium-10 and carbon-14 concentrations in recently exposed bedrock at the margin of four glaciers spanning the tropical Andes to reconstruct their past extents relative to today. Nuclide concentrations are near zero in almost all samples, suggesting that these locations were never exposed during the Holocene. Our data imply that many glaciers in the tropics are probably now smaller than they have been in at least 11,700 years, making the tropics the first large region where this milestone has been documented.