Coccolithophore estimates of paleotemperature and paleoproductivity changes in the Southeast Pacific over the past ∼27 kyr

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doi: 10.1029/2009PA001824
Author(s): Saavedra-Pellitero, M.; Flores, J. A.; Lamy, F.; Sierro, F. J.; Cortina, A.
Author Affiliation(s): Primary:
University of Salamanca, Department of Geology, Salamanca, Spain
Alfred Wegener Institute for Polar and Marine Research, Germany
Volume Title: Paleoceanography
Source: Paleoceanography, 26(1). Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0883-8305 CODEN: POCGEP
Note: In English. Includes appendices. 93 refs.; illus., incl. 5 tables, sketch map
Summary: We provide high-resolution sea surface temperature (SST) and paleoproductivity data focusing on Termination 1. We describe a new method for estimating SSTs based on multivariate statistical analyses performed on modern coccolithophore census data, and we present the first downcore reconstructions derived from coccolithophore assemblages at Ocean Drilling Project (ODP) Site 1233 located offshore Chile. We compare our coccolithophore SST record to alkenone-based SSTs as well as SST reconstructions based on dinoflagellates and radiolaria. All reconstructions generally show a remarkable concordance. As in the alkenone SST record, the Last Glacial Maximum (LGM, 19-23 kyr B.P.) is not clearly defined in our SST reconstruction. After the onset of deglaciation, three major warming steps are recorded: from 18.6 to 18 kyr B.P. (∼2.6°C), from 15.7 to 15.3 kyr B.P. (∼2.5°C), and from 13 to 11.4 kyr B.P. (∼3.4°C). Consistent with the other records from Site 1233 and Antarctic ice core records, we observed a clear Holocene Climatic Optimum (HCO) from ∼8-12 kyr B.P. Combining the SST reconstruction with coccolith absolute abundances and accumulation rates, we show that colder temperatures during the LGM are linked to higher coccolithophore productivity offshore Chile and warmer SSTs during the HCO to lower coccolithophore productivity, with indications of weak coastal upwelling. We interpret our data in terms of latitudinal displacements of the Southern Westerlies and the northern margin of the Antarctic Circumpolar Current system over the deglaciation and the Holocene.
Year of Publication: 2011
Research Program: ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Algae; Alkenones; Biostratigraphy; Cenozoic; Chile; Coccolithophoraceae; Continental margin; Cores; Deglaciation; East Pacific; Foraminifera; Holocene; Invertebrata; Ketones; Leg 202; Marine sediments; Microfossils; Multivariate analysis; Nannofossils; ODP Site 1233; Ocean Drilling Program; Organic compounds; Pacific Ocean; Paleo-oceanography; Paleoclimatology; Paleoenvironment; Paleotemperature; Plantae; Pleistocene; Principal components analysis; Productivity; Protista; Quaternary; Reconstruction; Sea-surface temperature; Sediments; South America; South Pacific; Southeast Pacific; Statistical analysis; Upper Pleistocene
Coordinates: S410000 S410000 W0742700 W0742700
Record ID: 2013009829
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