Dataset Information

1,500 year quantitative reconstruction of winter precipitation in the Pacific Northwest.

ABSTRACT: Multiple paleoclimate proxies are required for robust assessment of past hydroclimatic conditions. Currently, estimates of drought variability over the past several thousand years are based largely on tree-ring records. We produced a 1,500-y record of winter precipitation in the Pacific Northwest using a physical model-based analysis of lake sediment oxygen isotope data. Our results indicate that during the Medieval Climate Anomaly (MCA) (900-1300 AD) the Pacific Northwest experienced exceptional wetness in winter and that during the Little Ice Age (LIA) (1450-1850 AD) conditions were drier, contrasting with hydroclimatic anomalies in the desert Southwest and consistent with climate dynamics related to the El Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO). These findings are somewhat discordant with drought records from tree rings, suggesting that differences in seasonal sensitivity between the two proxies allow a more compete understanding of the climate system and likely explain disparities in inferred climate trends over centennial timescales.

SUBMITTER: Steinman BA

PROVIDER: S-EPMC3406856 | biostudies-other | 2012 Jul

REPOSITORIES: biostudies-other

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1,500 year quantitative reconstruction of winter precipitation in the Pacific Northwest.

Steinman Byron A BA Abbott Mark B MB Mann Michael E ME Stansell Nathan D ND Finney Bruce P BP

Proceedings of the National Academy of Sciences of the United States of America 20120702 29

Multiple paleoclimate proxies are required for robust assessment of past hydroclimatic conditions. Currently, estimates of drought variability over the past several thousand years are based largely on tree-ring records. We produced a 1,500-y record of winter precipitation in the Pacific Northwest using a physical model-based analysis of lake sediment oxygen isotope data. Our results indicate that during the Medieval Climate Anomaly (MCA) (900-1300 AD) the Pacific Northwest experienced exceptiona ...[more]

PMID: 22753510

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Dataset Information

1,500 year quantitative reconstruction of winter precipitation in the Pacific Northwest.

Publications

1,500 year quantitative reconstruction of winter precipitation in the Pacific Northwest.

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