Rapid shifts in subarctic Pacific climate between 138 and 70 ka

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doi: 10.1130/G35879.1
Author(s): Max, Lars; Belz, Lukas; Tiedemann, Ralf; Fahl, Kirsten; Nürnberg, Dirk; Riethdorf, Jan-Rainer
Author Affiliation(s): Primary:
Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
Helmholtz-Zentrum Potsdam, Germany
Helmholtz-Zentrum für Ozeanforschung, Germany
Volume Title: Geology (Boulder)
Source: Geology (Boulder), 42(10), p.899-902. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0091-7613 CODEN: GLGYBA
Note: In English. GSA Data Repository item 2014317. 32 refs.; illus., incl. sketch map
Summary: During the past decades, remarkable changes in sea-surface temperature (SST) and sea-ice extent have been observed in the marginal seas of the subarctic Pacific. However, little is known about natural climate variability at millennial time scales far beyond instrumental observations. Geological proxy records, such as those derived from marine sediments, offer a unique opportunity to investigate millennial-scale natural climate variability of the Arctic and subarctic environments during past glacial-interglacial cycles. Here we provide reconstructions of sea-ice variability inferred from IP25 (Ice Proxy with 25 carbon atoms) sea-ice biomarker and SST fluctuations based on alkenone unsaturation index (Formula ) of the subarctic Pacific realm between 138 and 70 ka. Warmest sea-surface conditions were found during the early Eemian interglacial (128 to 126 ka), exceeding modern SSTs by ∼2 °C. The further North Pacific climate evolution is marked by pronounced oscillations in SST and sea-ice extent on millennial time scales, which correspond remarkably well to short-term temperature oscillations known from Greenland and the North Atlantic. These results imply a common forcing, which seems to be closely coupled to dynamics of the Atlantic meridional overturning circulation. However, immediate propagation of such climate fluctuations far beyond the North Atlantic basin suggests a rapid circumpolar coupling mechanism probably acting through the atmosphere, a prerequisite to explain the apparent synchronicity of remote climatic reorganizations in the subarctic Pacific.
Year of Publication: 2014
Research Program: ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Alkenones; Arctic region; Atlantic Ocean; Bering Sea; Biomarkers; Cenozoic; Chemostratigraphy; Chronostratigraphy; Climate change; Cores; Correlation; Greenland; Ice cores; Isotope ratios; Isotopes; Ketones; Leg 162; Lithostratigraphy; Marine sediments; NGRIP; North Atlantic; North Pacific; O-18/O-16; ODP Site 980; Ocean Drilling Program; Organic compounds; Oxygen; Pacific Ocean; Paleo-oceanography; Paleoclimatology; Paleotemperature; Pleistocene; Quaternary; Rockall Bank; Sea-surface temperature; Sediments; Stable isotopes; Subarctic regions; Upper Pleistocene
Coordinates: N552906 N552906 W0144208 W0144208
Record ID: 2014082862
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from GeoScienceWorld, Alexandria, VA, United States, Reference includes data supplied by the Geological Society of America