A global sediment trap database of Mg/Ca in planktic foraminifera Globigerinoides ruber

Abstract: 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 ([CO3**2-]) 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 [CO3**2-] sensitivity of -0.24 ± 0.11/µmol kg**1. 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 [CO3**2-] is the controlling parameter.

Category: geoscientificInformation

Source: 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, https://doi.org/10.1016/j.epsl.2017.11.026

Supplemental Information: Not Availble

Coverage: EVENT LABEL: CB_trap * LATITUDE: 21.633000 * LONGITUDE: -20.183300 * LOCATION: off Cap Blanc * METHOD/DEVICE: Trap
EVENT LABEL: CBi3 * LATITUDE: 20.760000 * LONGITUDE: -18.765000 * DATE/TIME START: 2005-07-25T00:00:00 * DATE/TIME END: 2006-09-28T00:00:00 * ELEVATION: -2693.0 m * LOCATION: Cape Blanc * CAMPAIGN: POS344/1 * BASIS: Poseidon * METHOD/DEVICE: Trap
EVENT LABEL: GOC_trap * LATITUDE: 27.880000 * LONGITUDE: -111.670000 * ELEVATION: -485.0 m * LOCATION: Guaymas Basin, Gulf of California * METHOD/DEVICE: Trap, sediment
EVENT LABEL: JAM-1 * LATITUDE: -8.291700 * LONGITUDE: 108.033300 * DATE/TIME START: 2000-11-09T00:00:00 * DATE/TIME END: 2001-12-10T00:00:00 * ELEVATION: -2200.0 m * LOCATION: off south Java * METHOD/DEVICE: Mooring
EVENT LABEL: JAM-2 * LATITUDE: -8.291700 * LONGITUDE: 108.033300 * ELEVATION: -2200.0 m * LOCATION: off south Java * METHOD/DEVICE: Mooring
EVENT LABEL: M31/3_MSN913 (110, M31/3-110.4_MSN1) * LATITUDE: 16.201000 * LONGITUDE: 60.268000 * DATE/TIME: 1995-03-14T18:22:00 * ELEVATION: -4070.0 m * CAMPAIGN: M31/3 * BASIS: Meteor (1986) * METHOD/DEVICE: Multiple opening/closing net
EVENT LABEL: M32/5_MSN974 (414) * LATITUDE: 14.446667 * LONGITUDE: 65.015000 * DATE/TIME: 1995-07-27T11:51:00 * ELEVATION: -3937.0 m * LOCATION: Indian Ocean * CAMPAIGN: M32/5 * BASIS: Meteor (1986) * METHOD/DEVICE: Multiple opening/closing net
EVENT LABEL: M33/1_MSN1007 (601) * LATITUDE: 16.153250 * LONGITUDE: 60.428100 * DATE/TIME: 1995-09-30T11:36:00 * ELEVATION: -4029.0 m * LOCATION: Arabian Sea * CAMPAIGN: M33/1 * BASIS: Meteor (1986) * METHOD/DEVICE: Multiple opening/closing net
EVENT LABEL: MD122-PT10 * LATITUDE: -0.263300 * LONGITUDE: 134.209200 * DATE/TIME START: 2001-05-12T00:00:00 * DATE/TIME END: 2001-05-12T00:10:00 * ELEVATION: -50.0 m * LOCATION: Cenderawasih Bay * CAMPAIGN: MD122 * BASIS: Marion Dufresne (1995) * METHOD/DEVICE: Towed zooplankton net
EVENT LABEL: MD122-PT12 * LATITUDE: 6.729800 * LONGITUDE: 122.914300 * DATE/TIME START: 2001-05-16T03:30:00 * DATE/TIME END: 2001-05-16T03:40:00 * ELEVATION: -50.0 m * LOCATION: Sulu Sea * CAMPAIGN: MD122 * BASIS: Marion Dufresne (1995) * METHOD/DEVICE: Towed zooplankton net
EVENT LABEL: MD122-PT17 * LATITUDE: 24.828000 * LONGITUDE: 122.620700 * DATE/TIME START: 2001-05-25T07:45:00 * DATE/TIME END: 2001-05-25T07:55:00 * ELEVATION: 0.0 m * LOCATION: South China Sea * CAMPAIGN: MD122 * BASIS: Marion Dufresne (1995) * METHOD/DEVICE: Towed zooplankton net
EVENT LABEL: MD122-PT18 * LATITUDE: 25.340800 * LONGITUDE: 122.478200 * DATE/TIME START: 2001-05-27T15:10:00 * DATE/TIME END: 2001-02-27T15:25:00 * ELEVATION: -5.0 m * LOCATION: Formosa Strait * CAMPAIGN: MD122 * BASIS: Marion Dufresne (1995) * METHOD/DEVICE: Towed zooplankton net
EVENT LABEL: MD122-PT26 * LATITUDE: 36.120000 * LONGITUDE: 141.890000 * CAMPAIGN: MD122 * BASIS: Marion Dufresne (1995) * METHOD/DEVICE: Towed zooplankton net
EVENT LABEL: MOZ1_trap * LATITUDE: -16.200000 * LONGITUDE: 41.000000 * LOCATION: Mozambique Channel * METHOD/DEVICE: Trap, sediment
EVENT LABEL: MOZ2 * LATITUDE: -16.200000 * LONGITUDE: 41.000000 * LOCATION: Mozambique Channel * METHOD/DEVICE: Trap, sediment
EVENT LABEL: MS-5 * LATITUDE: 10.000000 * LONGITUDE: 65.000000 * METHOD/DEVICE: Mooring
EVENT LABEL: NBBT-09 * LATITUDE: 17.380000 * LONGITUDE: 89.700000 * LOCATION: Bay of Bengal * METHOD/DEVICE: Trap, sediment
EVENT LABEL: OFP_trap (Oceanic Flux Program) * LATITUDE: 32.080000 * LONGITUDE: -64.250000 * LOCATION: Bermuda * METHOD/DEVICE: Trap, sediment
EVENT LABEL: SCIFF_site * LATITUDE: 32.090000 * LONGITUDE: -64.256700 * LOCATION: Sargasso Sea * METHOD/DEVICE: Trap, sediment
EVENT LABEL: SCS_M1s_trap * LATITUDE: 21.530000 * LONGITUDE: 119.450000 * ELEVATION: -2943.0 m * LOCATION: South China Sea * METHOD/DEVICE: Trap, sediment
EVENT LABEL: SCS_M2_trap * LATITUDE: 19.020000 * LONGITUDE: 117.530000 * ELEVATION: -3743.0 m * LOCATION: South China Sea * METHOD/DEVICE: Trap, sediment
EVENT LABEL: SCS_M3_trap * LATITUDE: 20.510000 * LONGITUDE: 118.240000 * ELEVATION: -2626.0 m * LOCATION: South China Sea * METHOD/DEVICE: Trap, sediment
EVENT LABEL: SO119_MSN1284 * LATITUDE: 16.201933 * LONGITUDE: 60.307833 * DATE/TIME: 1997-05-24T05:09:00 * ELEVATION: -4047.0 m * LOCATION: Arabian Sea * CAMPAIGN: SO119 * BASIS: Sonne * METHOD/DEVICE: Multiple opening/closing net