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  • A Link Between Hydroclimate Variability and Biomass Burning During the Last Millennium in the Interior Pacific Northwest
Title: A Link Between Hydroclimate Variability and Biomass Burning During the Last Millennium in the Interior Pacific Northwest
We present oxygen isotope and charcoal accumulation records from two lakes in eastern Washington that have sufficient temporal resolution to quantitatively compare with tree‐ring records and meteorological data. Hydroclimate reconstructions from tree‐rings and lake sediments show close correspondence after accounting for seasonal‐ to centennial‐ scale temporal sensitivities. Carbonate δ18O measurements from Castor and Round lakes reveal that the Medieval Climate Anomaly (MCA) experienced wetter November‐March conditions than the Little Ice Age (LIA). Charcoal records from Castor, Round, and nearby lakes show elevated fire activity during the LIA compared to the MCA. Increased multidecadal hydroclimate variability after 1250 CE is evident in proxy records throughout western North America. In the Upper Columbia River Basin, multidecadal wet periods during the LIA may have enhanced fuel loads that burned in subsequent dry periods. A notable decline in biomass burning occurred with Euro‐American settlement in the late nineteenth century.  more » « less
Award ID(s):
2149482
PAR ID:
10499521
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Geophysical Union
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
50
Issue:
21
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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