A preliminary assessment of hemispheric climate symmetry during the Pliocene; insights from ODP 1088

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doi: 10.1130/abs/2016NE-271727
Author(s): Mauriello, Haley E.; Lawrence, Kira T.; Peterson, Laura C.
Author Affiliation(s): Primary:
Lafayette College, Department of Geology and Environmental Geosciences, Easton, PA, United States
Other:
Luther College, United States
Volume Title: Geological Society of America, Northeastern Section, 51st annual meeting
Source: Abstracts with Programs - Geological Society of America, 48(2); Geological Society of America, Northeastern Section, 51st annual meeting, Albany, NY, March 21-23, 2016. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0016-7592 CODEN: GAAPBC
Note: In English
Summary: The Pliocene (5.3-2.7 Mya) was the most recent interval of sustained warmth (∼3°C warmer on average globally than pre-industrial) and the most recent interval that the atmospheric concentration of carbon dioxide was comparable to modern at ∼400ppm. As a result, the Pliocene has been studied as a possible analog for future climate change. Previous studies suggest fairly hemispherically symmetric responses to forcing on long-time scales (millions of years). Here, we explore the coordination of the climate system on orbital (10,000 year) timescales by presenting a ∼3 kyr resolution, alkenone-derived, sea surface temperature (SST) record from Ocean Drilling Program (ODP) Site 1088 (41S, 13.5E, 2082m water depth) in the South Atlantic Ocean. We examine the hemispheric and interbasin symmetry of SST on orbital timescales. Our Site 1088 SST and productivity records demonstrate no long-term trend but strong glacial-interglacial variations (∼3°C in magnitude on average) from 3.8-2.4 Ma. Additionally, novel pronounced coolings (∼5-6C) are evident in this record antecedent to the start of Northern Hemisphere Glaciation (NHG) (2.7 Ma). One of these excursions corresponds to Marine Isotope Stage (MIS) M2, long considered a first failed attempt at NHG. We compare our SST record from Site 1088 with another S. Atlantic site (ODP 1090), a N. Atlantic site (Deep Sea Drilling Program (DSDP) 607), a S. Pacific site (ODP 1125), a tropical Atlantic site (ODP 662), and a tropical Pacific site (ODP 846). We find significantly different absolute temperatures, but quite similar variance in records from similar latitudes. Relatable features between the 1088 record and those from other localities demonstrate the viability of this site for paleoclimate reconstructions. These comparisons between records in different hemispheres and ocean basins indicate a broadly global response to changes in forcing on orbital timescales, despite a significant difference in glacial extent between hemispheres.
Year of Publication: 2016
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Alkenones; Atlantic Ocean; Cenozoic; Chatham Rise; DSDP Site 607; Deep Sea Drilling Project; East Pacific; Equatorial Atlantic; Equatorial Pacific; IPOD; Ketones; Leg 108; Leg 138; Leg 177; Leg 181; Leg 94; Mid-Atlantic Ridge; Neogene; North Atlantic; Northeast Atlantic; ODP Site 1088; ODP Site 1090; ODP Site 1125; ODP Site 662; ODP Site 846; Ocean Drilling Program; Organic compounds; Pacific Ocean; Paleoclimatology; Paleotemperature; Pliocene; Sea-surface temperature; South Atlantic; South Pacific; Southeast Pacific; Tertiary
Coordinates: S410810 S410810 E0133346 E0133346
N410004 N410005 W0325726 W0325727
S012325 S012324 W0114421 W0114421
S030549 S030541 W0904904 W0904906
Record ID: 2016083221
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States