Oelkers, Lisa S; Vázquez Riveiros, Natalia; Frick, Daniel A; Jebasinski, Lena; Waelbroeck, Claire; Skinner, Luke C; Gottschalk, Julia: Seawater δ18O and bottom water salinity reconstructions based on paired Uvigerina spp. Mg/Ca and δ18O analyses in sediment core MD07-3077 from the Subantarctic Atlantic Ocean for Marine Isotope Stage 12-10 [dataset]. PANGAEA, https://doi.pangaea.de/10.1594/PANGAEA.993721 (dataset in review)
Abstract:
This dataset presents seawater δ18O (δ18Ow) and bottom water temperature (BWT) reconstructions from Subantarctic Atlantic sediment core MD07-3077 (44.15°S, 14.23°E; 3,770 m water depth) from MIS 12 to 10 (424-374 ka before present) based on paired Uvigerina spp. Mg/Ca ratios and δ18O measurements. Paired Uvigerina spp. δ18O- and Mg/Ca-based BWT reconstructions allow a quantification of ice volume-corrected, local bottom water δ18O (δ18Ow-ice), and hence variations in bottom water salinity (BWS) at site MD07-3077, provided global ice volume changes (δ18Oice) are known or can be approximated (Roberts et al., 2016). Uvigerina spp. Mg/Ca levels were converted to BWT based on the calibration of Roberts et al. (2016). Local variations in δ18Ow and δ18Ow-ice independent from the waxing and waning of continental ice sheets at the core site of MD07-3077 were quantified after Elderfield et al. (2012) and Roberts et al. (2016). To obtain δ18Ow at the study site, the temperature component (i.e., Uvigerina spp. Mg/Ca-based BWT) was removed from measured Uvigerina spp. δ18O via the paleotemperature equation of Elderfield et al. (2010). To produce continuous time series with an equally spaced age axis that accounts for differences in temporal resolution of the individual records, a generalized least squares interpolation was implemented for our BWT and Uvigerina spp. δ18O records. The δ18Ow data were corrected by changes in global ice volume (δ18Oice) based on simulations of Clark et al. (2025) in order to estimate variations in δ18Ow-ice. Reconstructed δ18Ow and δ18Ow-ice are expressed against the Vienna Standard Mean Ocean Water (VSMOW) reference scale. To translate δ18Ow-ice changes into BWS deviations from present-day values, the modern sensitivity of variations in δ18Ow-ice of 0.24±0.014 ‰ per salinity unit change of LeGrande & Schmidt (2006) was applied.
References:
Clark, Peter U; Shakun, Jeremy D; Rosenthal, Yair; Pollard, David; Hostetler, Steven W; Köhler, Peter; Bartlein, Patrick J; Gregory, Jonathan M; Zhu, Chenyu; Schrag, Daniel P; Liu, Zhengyu; Pisias, Nicklas G (2025): Global mean sea level over the past 4.5 million years. Science, 390(6770), eadv8389, https://doi.org/10.1126/science.adv8389
Elderfield, Henry; Ferretti, Patrizia; Greaves, Mervyn; Crowhurst, Simon J; McCave, I Nicholas; Hodell, David A; Piotrowski, Alexander M (2012): Evolution of ocean temperature and ice volume through the Mid-Pleistocene Climate Transition. Science, 337(6095), 704-709, https://doi.org/10.1126/science.1221294
Elderfield, Henry; Greaves, Mervyn; Barker, S; Hall, Ian R; Tripati, Aradhna K; Ferretti, Patrizia; Crowhurst, Simon J; Booth, Linda; Daunt, C (2010): A record of bottom water temperature and seawater d18O for the Southern Ocean over the past 440kyr based on Mg/Ca of benthic foraminiferal Uvigerina spp. Quaternary Science Reviews, 29(1-2), 160-169, https://doi.org/10.1016/j.quascirev.2009.07.013
LeGrand, Allegra N; Schmidt, Gavin A (2006): Global gridded data set of the oxygen isotopic composition in seawater. Geophysical Research Letters, 33(12), L12604, https://doi.org/10.1029/2006GL026011
Roberts, Jenny; Gottschalk, Julia; Skinner, Luke C; Peck, Victoria L; Kender, Sev; Elderfield, Henry; Waelbroeck, Claire; Vázquez Riveiros, Natalia; Hodell, David A (2016): Evolution of South Atlantic density and chemical stratification across the last deglaciation. Proceedings of the National Academy of Sciences, 113(3), 514-519, https://doi.org/10.1073/pnas.1511252113
Funding:
Coverage:
Latitude: -44.150000 * Longitude: -14.220000
Date/Time Start: 2007-01-25T14:32:00 * Date/Time End: 2007-01-25T14:32:00
Minimum Elevation: -3770.0 m * Maximum Elevation: -3770.0 m
Event(s):
MD07-3077 * Latitude: -44.150000 * Longitude: -14.220000 * Date/Time: 2007-01-25T14:32:00 * Elevation: -3770.0 m * Campaign: MD159 (IMAGES XV - Pachiderme) * Basis: Marion Dufresne (1995) * Method/Device: Calypso Corer II (CALYPSO2)
Parameter(s):
| # | Name | Short Name | Unit | Principal Investigator | Method/Device | Comment |
|---|---|---|---|---|---|---|
| 1 | AGE | Age | ka BP | Gottschalk, Julia | Geocode | |
| 2 | Bottom water temperature | BWT | °C | Gottschalk, Julia | Reconstructed | |
| 3 | Bottom water temperature, uncertainty | BWT unc | ± | Gottschalk, Julia | Reconstructed | |
| 4 | δ18O, water | δ18O H2O | ‰ SMOW | Gottschalk, Julia | vs. VSMOW | |
| 5 | δ18O, water, uncertainty | δ18O H2O unc | ± | Gottschalk, Julia | ||
| 6 | δ18O, seawater, reconstructed | δ18Osw | ‰ SMOW | Gottschalk, Julia | Reconstructed | vs. VSMOW |
| 7 | δ18O, seawater, reconstructed, uncertainty | δ18Osw unc | ± | Gottschalk, Julia | Reconstructed | |
| 8 | δ18O, ice volume free, seawater | δ18O ivf sw | ‰ SMOW | Gottschalk, Julia | Reconstructed | vs. VSMOW; ice volume-corrected, local bottom water |
| 9 | δ18O, ice volume free, seawater, uncertainty | δ18O ivf sw unc | ± | Gottschalk, Julia | Reconstructed | |
| 10 | Bottom water salinity | BWS | Gottschalk, Julia | Reconstructed | psu | |
| 11 | Bottom water salinity, uncertainty | BWS unc | ± | Gottschalk, Julia | Reconstructed |
License:
Creative Commons Attribution 4.0 International (CC-BY-4.0) (License comes into effect after moratorium ends)
Status:
Curation Level: Enhanced curation (CurationLevelC)
Size:
3850 data points
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