Subtropical sea-surface warming and increased salinity during Eocene Thermal Maximum 2

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doi: 10.1130/G39658.1
Author(s): Harper, Dustin T.; Zeebe, Richard; Hönisch, Bärbel; Schrader, Cindy D.; Lourens, Lucas J.; Zachos, James C.
Author Affiliation(s): Primary:
University of California at Santa Cruz, Department of Earth and Planetary Sciences, Santa Cruz, CA, United States
University of Hawaii at Manoa, United States
Columbia University, United States
Utrecht University, Netherlands
Volume Title: Geology (Boulder)
Source: Geology (Boulder), 46(2), p.187-190. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0091-7613 CODEN: GLGYBA
Note: In English. 37 refs.; illus., incl. sketch map
Summary: Eocene Thermal Maximum 2 (ETM-2; ca. 54.2 Ma) represents the second largest of the major Eocene hyperthermals, yet comparatively little is known about the scale and rate of climatic change for key regions. Here we provide the first detailed records of subtropical sea-surface warming and salinization for ETM-2 at two subtropical locations, Ocean Drilling Program Sites 1209 (North Pacific) and 1265 (South Atlantic). Coupled planktic foraminiferal Mg/Ca and δ18O indicate 2-4 °C of rapid warming and local salinization of ∼1-2 ppt at both sites. The increase in sea-surface temperature is equivalent to anomalies reported from higher latitude sites, and is consistent with theory on the expected pattern of spatial temperature response to greenhouse gas forcing in an ice-free world (i.e., no ice-albedo feedback). Similarly, the observed salinization is consistent with the hypothesis of enhanced meridional vapor transport and increased subtropical aridity in a warmer world.
Year of Publication: 2018
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Alkaline earth metals; Atlantic Ocean; C-13/C-12; Calcium; Carbon; Cenozoic; Chemostratigraphy; Climate change; Cores; Eocene; Eocene Thermal Maximum 2; Foraminifera; Global change; Global warming; Isotope ratios; Isotopes; Leg 198; Leg 208; Lithofacies; Magnesium; Marine environment; Metals; Mg/Ca; Microfossils; North Pacific; Northwest Pacific; O-18/O-16; ODP Site 1209; ODP Site 1265; Ocean Drilling Program; Oxygen; Pacific Ocean; Paleo-oceanography; Paleocene-Eocene Thermal Maximum; Paleoclimatology; Paleogene; Paleosalinity; Paleotemperature; Shatsky Rise; South Atlantic; Sr/Ca; Stable isotopes; Strontium; Tertiary; Walvis Ridge; West Pacific
Coordinates: N323900 N324000 E1583100 E1583000
S285000 S285000 E0023800 E0023800
Record ID: 2018041868
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