A global sediment trap database of Mg/Ca in planktic foraminifera Globigerinoides ruber, supplement to: Gray, William R; Weldeab, Syee; Lea, David W; Rosenthal, Yair; Gruber, Nicolas; Donner, Barbara; Fischer, Gerhard (2018): The effects of temperature, salinity, and the carbonate system on Mg/Ca in Globigerinoides ruber (white): A global sediment trap calibration. Earth and Planetary Science Letters, 482, 607-620

DOI

The Mg/Ca of planktic foraminifera Globigerinoides ruber (white) is a widely applied proxy for tropical and sub-tropical sea-surface temperature. The accuracy with which temperature can be reconstructed depends on how accurately relationships between Mg/Ca and temperature and the multiple secondary controls on Mg/Ca are known; however, these relationships remain poorly quantified under oceanic conditions. Here, we present new calibrations based on 440 sediment trap/plankton tow samples from the Atlantic, Pacific and Indian Oceans, including 130 new samples from the Bay of Bengal/Arabian Sea and the tropical Atlantic Ocean. Our results indicate temperature, salinity and the carbonate system all significantly influence Mg/Ca in G. ruber (white). We propose two calibration models: The first model assumes pH is the controlling carbonate system parameter. In this model, Mg/Ca has a temperature sensitivity of 6.0 ± 0.8 %/°C (2 Sigma), a salinity sensitivity of 3.3 ± 2.2%/PSU and a pH sensitivity of -8.3 ± 7.7%/0.1 pH units; The second model assumes carbonate ion concentration ([CO32-]) is the controlling carbonate system parameter. In this model, Mg/Ca has a temperature sensitivity of 6.7 ± 0.8%/°C, a salinity sensitivity of 5.0 ± 3.0%/PSU and a [CO32-] sensitivity of -0.24 ± 0.11/µmol kg1. In both models, the temperature sensitivity is significantly lower than the widely-applied sensitivity of 9.0 ± 0.6%/°C. Application of our new calibrations to down-core data from the Last Glacial Maximum, considering whole ocean changes in salinity and carbonate chemistry, indicate a cooling of 2.4 ± 1.6 °C in the tropical oceans if pH is the controlling parameter and 1.5 ± 1.4 °C if [CO32-] is the controlling parameter.

Identifier
DOI http://dx.doi.org/doi:10.1594/PANGAEA.885877
Metadata Access http://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite3&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.885877
Provenance
Creator Fischer, Gerhard;Weldeab, Syee;Lea, David W;Donner, Barbara;Gray, William R;Rosenthal, Yair;Gruber, Nicolas
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 2018
Rights Creative Commons Attribution 3.0 Unported (CC-BY)
Representation
Language English
Resource Type Supplementary Dataset
Format text/tab-separated-values
Coverage
Discipline Earth System Research
Spatial Coverage (16S-36N,112W-142E)
Temporal Point 1995-03-14T11:59:59Z