Pliocene pre-glacial North Atlantic: A coupled sea surface-deep ocean circulation climate response

Conference · Wed Jan 01 04:00:00 EST 1992 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5590415

Ishman, S E; Dowsett, H J ^[1]

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1. Geological Survey, Reston, VA (United States). National Center

A latitudinal transect of North Atlantic Deep Sea Drilling Project Holes from the equatorial region to 56 N in the 2,300- to 3,000-meter depth range was designed for a high-resolution study of coupled sea surface and deep ocean response to climate change. Precise age control was provided using magnetostratigraphic and biostratigraphic data from the cores to identify the 4.0 to 2.2 Ma interval, a period of warm-to-cool climatic transitions in the North Atlantic. The objective is to evaluate incremental (10 kyr) changes in sea surface temperatures (SST) and deep North Atlantic circulation patterns between 4.0 and 2.2 Ma to develop a coupled sea surface-deep ocean circulation response model. Sea surface temperature (SST) estimates are based on planktic foraminifer-based factor-analytic transfer functions. Oxygen isotopic data from paired samples provide tests of the estimated temperature gradients between localities. Benthic foraminifer assemblage data and [partial derivative]O-18 and [partial derivative]C-13 Isotopic data are used to quantitatively determine changes in deep North Atlantic circulation. These data are used to determine changes in source area (North Atlantic Deep Water (NADW) or Antarctic Bottom Water) and (or) in the components of NADW that were present (Upper or Lower NADW). These paired paleoceanographic sea surface and deep circulation interpretations over a 1.8 my interval form the basis for a coupled sea surface-deep circulation response model for the Pliocene North Atlantic Ocean.

• OSTI ID: 5590415
• Report Number(s): CONF-921058--
• Conference Information: Journal Name: Geological Society of America, Abstracts with Programs; (United States) Journal Volume: 24:7
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
ATLANTIC OCEAN
CENOZOIC ERA
CLIMATE MODELS
CLIMATIC CHANGE
DRILL CORES
DRILLING
FUNCTIONS
GEOLOGIC AGES
ISOTOPE RATIO
MATHEMATICAL MODELS
OCEANIC CIRCULATION
OCEANOGRAPHY
PALEOCLIMATOLOGY
PALEONTOLOGY
PALEOTEMPERATURE
PLIOCENE EPOCH
RESPONSE FUNCTIONS
SEA BED
SEAS
SURFACE WATERS
TERTIARY PERIOD