Evidence of Temperature Depression and Hydrological Variations in the Eastern Sierra Nevada during the Younger Dryas Stade

Sediment records from two lakes in the east-central Sierra Nevada, California, provide evidence of cooling and hydrological shifts during the Younger Dryas stade (YD; ~ 12,900–11,500 cal yr BP). A chironomid transfer function suggests that lake-water temperatures were depressed by 2°C to 4°C relativ...

Full description

Bibliographic Details
Published in:Quaternary Research
Main Authors: MacDonald, Glen M., Moser, Katrina A., Bloom, Amy M., Porinchu, David F., Potito, Aaron P., Wolfe, Brent B., Edwards, Thomas W. D., Petel, Amanda, Orme, Antony R., Orme, Amalie Jo
Format: Article in Journal/Newspaper
Language:unknown
Published: Scholarship@Western 2008
Subjects:
Quaternary
Younger Dryas stade
Climate change
Vegetation change
Sierra Nevada
California
Paleoclimatology
Paleohydrology
Paleolimnology
Geography
Pacific
North Atlantic
Online Access:https://ir.lib.uwo.ca/geographypub/124
https://doi.org/10.1016/j.yqres.2008.04.005
Description
Summary:Sediment records from two lakes in the east-central Sierra Nevada, California, provide evidence of cooling and hydrological shifts during the Younger Dryas stade (YD; ~ 12,900–11,500 cal yr BP). A chironomid transfer function suggests that lake-water temperatures were depressed by 2°C to 4°C relative to maximum temperatures during the preceding Bølling–Allerød interstade (BA; ~ 14,500–12,900 cal yr BP). Diatom and stable isotope records suggest dry conditions during the latter part of the BA interstade and development of relatively moist conditions during the initiation of the YD stade, with a reversion to drier conditions later in the YD. These paleohydrological inferences correlate with similar timed changes detected in the adjacent Great Basin. Vegetation response during the YD stade includes the development of more open and xeric vegetation toward the end of the YD. The new records support linkages between the North Atlantic, the North Pacific, and widespread YD cooling in western North America, but they also suggest complex hydrological influences. Shifting hydrological conditions and relatively muted vegetation changes may explain the previous lack of evidence for the YD stade in the Sierra Nevada and the discordance in some paleohydrological and glacial records of the YD stade from the western United States.

Similar Items