700,000 years of tropical Andean glaciation

• Published in: Nature (London) Vol. 607; no. 7918; pp. 301 - 306
• Main Authors: Rodbell, D. T., Hatfield, R. G., Abbott, M. B., Chen, C. Y., Woods, A., Stoner, J. S., McGee, D., Tapia, P. M., Bush, M., Valero-Garcés, B. L., Lehmann, S. B., Mark, S. Z., Weidhaas, N. C., Hillman, A. L., Larsen, D. J., Delgado, G., Katz, S. A., Solada, K. E., Morey, A. E., Finkenbinder, M., Valencia, B., Rozas-Davila, A., Wattrus, N., Colman, S. M., Bustamante, M. G., Kück, J., Pierdominici, S.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14.07.2022; Nature Publishing Group
• Subjects: 704/106/286; 704/106/413; Archives & records; Catchments; Cerebral hemispheres; Climate teleconnections; ENVIRONMENTAL SCIENCES; Glacial deposits; Glaciation; Glaciers; Glaciology; Humanities and Social Sciences; Hydrology; Ice; Ice sheets; Intervals; Lakes; Monsoon precipitation; Monsoons; multidisciplinary; Periodic variations; Periodicity; Perturbation; Precipitation; Science; Science (multidisciplinary); Sedimentation & deposition; Sediments; Wind; Greenland
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/s41586-022-04873-0

Our understanding of the climatic teleconnections that drove ice-age cycles has been limited by a paucity of well-dated tropical records of glaciation that span several glacial–interglacial intervals. Glacial deposits offer discrete snapshots of glacier extent but cannot provide the continuous records required for detailed interhemispheric comparisons. By contrast, lakes located within glaciated catchments can provide continuous archives of upstream glacial activity, but few such records extend beyond the last glacial cycle. Here a piston core from Lake Junín in the uppermost Amazon basin provides the first, to our knowledge, continuous, independently dated archive of tropical glaciation spanning 700,000 years. We find that tropical glaciers tracked changes in global ice volume and followed a clear approximately 100,000-year periodicity. An enhancement in the extent of tropical Andean glaciers relative to global ice volume occurred between 200,000 and 400,000 years ago, during sustained intervals of regionally elevated hydrologic balance that modified the regular approximately 23,000-year pacing of monsoon-driven precipitation. Millennial-scale variations in the extent of tropical Andean glaciers during the last glacial cycle were driven by variations in regional monsoon strength that were linked to temperature perturbations in Greenland ice cores 1 ; these interhemispheric connections may have existed during previous glacial cycles. Analysis of a continuous and independently dated record of glaciation in the tropical Andes spanning 700,000 years shows that Andean glaciation follows patterns of global ice volume change, with a periodicity of approximately 100,000 years.