Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published May 2017 | Published
Journal Article Open

Productivity patterns in the Equatorial Pacific over the last 30,000 years


The equatorial Pacific traverses a number of productivity regimes, from the highly productive coastal upwelling along Peru to the near gyre-like productivity lows along the international dateline, making it an ideal target for investigating how biogeochemical systems respond to changing oceanographic conditions over time. However, conflicting reconstructions of productivity during periods of rapid climate change, like the last deglaciation, render the spatiotemporal response of equatorial Pacific productivity ambiguous. In this study, surface productivity since the last glacial period (30,000 years ago) is reconstructed from seven cores near the Line Islands, central equatorial Pacific, and integrated with productivity records from across the equatorial Pacific. Three coherent deglacial patterns in productivity are identified: (1) a monotonic glacial-Holocene increase in productivity, primarily along the Equator, associated with increasing nutrient concentrations over time; (2) a deglacial peak in productivity ~15,000 years ago due to transient entrainment of nutrient rich southern-sourced deep waters; and (3) possible precessional cycles in productivity in the eastern equatorial Pacific that may be related to Intertropical Convergence Zone migration and potential interactions with El Niño–Southern Oscillation dynamics. These findings suggest that productivity was generally lower during the glacial period, a trend observed zonally across the equatorial Pacific, while deglacial peaks in productivity may be prominent only in the east.

Additional Information

© 2017 American Geophysical Union. Received 10 NOV 2016; Accepted 1 MAY 2017; Accepted article online 4 MAY 2017; Published online 21 MAY 2017. The authors thank Martin Fleisher for technical assistance with U-Th-Pa chemistry and ICP-MS analysis at LDEO. The authors also appreciate valuable reviews from Patrick Rafter and one anonymous reviewer that helped to improve this manuscript. The new data presented here are publically available in the NOAA paleoclimate repository upon acceptance. This research was funded in part by NSF-AGS 1502889 to J.F.M. and G.W. and a National Science Foundation Graduate Research Fellowship to K.M.C.

Attached Files

Published - 6b866d85d10841bcf123d94b074375505da76e16b0cd445deaa4db8b0c96755a.pdf


Files (4.7 MB)

Additional details

August 21, 2023
October 25, 2023