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Benson, L.V., M. Kashgarian, R. Rye, S.P. Lund, F. Paillet, J.P. Smoot, C. Kester, S. Mensing, D. Meko, S. Lindstrom. 2002.
Holocene multidecadal and multicentennial droughts affecting Northern California and Nevada. Quaternary Science Reviews Vol.
21, (4-6), pp. 659-682, February 2002
| Data Coverage |
North: 40.1 * South: 36.5 |
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West: -119.6 * East: -119 |
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Altitude: 1156 m |
Start Year: 224000 cal yr BP * End Year: 111 cal yr BP
Data: Please Cite Data Contributors!
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Summary: Continuous, high-resolution d18O records from cored sediments of Pyramid Lake, Nevada, indicate that oscillations in the
hydrologic balance occurred, on average, about every 150 years (yr) during the past 7630 calendar years (calyr). The records
are not stationary; during the past 2740yr, drought durations ranged from 20 to 100yr and intervals between droughts ranged
from 80 to 230yr. Comparison of tree-ring-based reconstructions of climate change for the past 1200yr from the Sierra Nevada
and the El Malpais region of northwest New Mexico indicates that severe droughts associated with Anasazi withdrawal from
Chaco Canyon at 820calyrBP (calendar years before present) and final abandonment of Chaco Canyon, Mesa Verde, and the Kayenta
area at 650calyrBP may have impacted much of the western United States. During the middle Holocene (informally defined in
this paper as extending from 8000 to 3000calyrBP), magnetic susceptibility values of sediments deposited in Pyramid Lake's
deep basin were much larger than late-Holocene (3000-0calyrBP) values, indicating the presence of a shallow lake. In addition,
the mean d18O value of CaCO3 precipitated between 6500 and 3430calyrBP was 1.6 less than the mean value of CaCO3 precipitated
after 2740calyrBP. Numerical calculations indicate that the shift in the d18O baseline probably resulted from a transition
to a wetter (>30%) and cooler (3-5°C) climate. The existence of a relatively dry and warm middle-Holocene climate in the
Truckee River-Pyramid Lake system is generally consistent with archeological, sedimentological, chemical, physical, and biological
records from various sites within the Great Basin of the western United States. Two high-resolution Holocene-climate records
are now available from the Pyramid and Owens lake basins which suggest that the Holocene was characterized by five climatic
intervals. TIC and d18O records from Owens Lake indicate that the first interval in the early Holocene (11,600-10,000calyrBP)
was characterized by a drying trend that was interrupted by a brief (200yr) wet oscillation centered at 10,300calyrBP. This
was followed by a second early-Holocene interval (10,000-8000calyrBP) during which relatively wet conditions prevailed.
During the early part of the middle Holocene (8000-6500calyrBP), high-amplitude oscillations in TIC in Owens Lake and d18O
in Pyramid Lake indicate the presence of shallow lakes in both basins. During the latter part of the middle Holocene (6500-3800calyrBP),
drought conditions dominated, Owens Lake desiccated, and Lake Tahoe ceased spilling to the Truckee River, causing Pyramid
Lake to decline. At the beginning of the late Holocene (~3000calyrBP), Lake Tahoe rose to its sill level and Pyramid Lake
increased in volume.
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