Extent of the Last Glacial Maximum (Tioga) glaciation in Yosemite National Park and vicinity, California

During the Last Glacial Maximum (Tioga glaciation), glaciers and ice fields covered most areas above 2,700 meters elevation in Yosemite National Park, sculpting iconic granite monoliths and influencing geological, hydrological, and ecological features. This study maps the extent of alpine icefields and valley glaciers during this period, identifying at least two major glacial advances between approximately 27,000 and 15,000 years ago, with the largest occurring from around 21,000 to 18,000 years ago. The research assumes simultaneous maximum extents for glaciers in the study area, though brief occupation is possible. Field evidence, including polished granite and linear scratches, provides abundant and well-preserved data, revealing the profound impact of Tioga glaciation on Yosemite's landscape.

Wahrhaftig, C., Stock, G. M., McCracken, R. G., Sasnett, P., & Cyr, A. J. (2019). Extent of the Last Glacial Maximum (Tioga) glaciation in Yosemite National Park and vicinity, California. Scientific Investigations Map. https://doi.org/10.3133/sim3414