Planktonic foraminifera distribution during the mid-Piacenzian warm period in the North Atlantic

• Main Author: Lutz, Brendan P
• Format: Other/Unknown Material
• Language: English
• Published: PANGAEA 2011
• Subjects: 157-951A; 159-958A; 166-1006A; 172-1062B; 172-1063A; Blake-Bahama Outer Ridge; North Atlantic Ocean; Canarias Sea; DRILL; Drilling/drill rig; Joides Resolution; Leg157; Leg159T; Leg166; Leg172; Ocean Drilling Program; ODP; north atlantic current; North Atlantic; Planktonic foraminifera
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.774590; https://doi.org/10.1594/PANGAEA.774590

The mid-Piacenzian (MP) warm period (3.264-3.025 Ma) has been identified as the most recent time in geologic history during which mean global surface temperatures were considerably warmer than today for a sustained period. This interval has therefore been proposed as a potential (albeit imperfect) analog for future climate change and as such, has received much scientific attention over the past two decades. Central to this research effort is the Pliocene Research, Interpretation, and Synoptic Mapping (PRISM) project, an iterative paleoenvironmental reconstruction of the MP focused on increasing our understanding of warm-period climate forcings, dynamics, and feedbacks by providing three-dimensional data sets for general circulation models. A mainstay of the PRISM project has been the development of a global sea surface temperature (SST) data set based primarily upon quantitative analyses of planktic foraminifer assemblages, supplemented with geochemical SST estimates wherever possible. In order to improve spatial coverage of the PRISM faunal data set in the low and mid-latitude North Atlantic, this study provides a description of the MP planktic foraminifer assemblage from five Ocean Drilling Program sites (951, 958, 1006, 1062, and 1063) in the subtropical gyre, a region critical to Atlantic Ocean circulation and tropical heat advection. Assemblages from each core provide evidence for a temperature- and circulation-driven 5-10° northward displacement of MP faunal provinces, as well as regional shifts in planktic foraminifer populations linked to species ecology and interactions. General biogeographic trends also indicate that, relative to modern conditions, gyre circulation was stronger (particularly the Gulf Stream, North Atlantic Current, and North Equatorial Current) and meridionally broader. A comparison of mid-Piacenzian and modern North Atlantic planktic foraminifer assemblages suggests that low latitude western boundary currents were less than 1 °C warmer while eastern boundary currents were ~1-2 °C ...