Diatom data from IN2017_V01: These data were generated by Amy Leventer (aleventer@colgate.edu) and undergraduate students at Colgate University, including Isabel Dove, Meghan Duffy, and Meaghan Kendall. All questions regarding the specifics of these data should be directed to Amy Leventer. These data are based on samples collected during research cruise IN2017_V01 of the RV Investigator, co-chief scientists, Leanne Armand and Phil O’Brien. The IN2017-V01post-cruise report is available through open access via the e-document portal through the ANU library. https://openresearch-repository.anu.edu.au/handle/1885/142525 The document DOI: 10.4225/13/5acea64c48693 The preferred citation is: L.K. Armand, P.E. O’Brien and On-board Scientific Party. 2018. Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles (IN2017-V01): Post-survey report, Research School of Earth Sciences, Australian National University: Canberra, http://dx.doi.org/10.4225/13/5acea64c48693 Samples for diatom analysis were collected on board ship immediately after core recovery. Samples were dried in an oven at 50 degrees C prior to analytical work. Quantitative diatom slides were prepared according to the settling technique of Warnock and Scherer (2014). Cover slips were adhered to the slides using Norland Optical Adhesive #61. Slides were observed under Olympus CX31, BX50 and BX60, and Zeiss Primo Star light microscopes, using a 100X oil immersion objective for a total magnification of 1000X. A minimum of 400 valves or 10 transects was counted for each slide, depending on the absolute diatom abundance. Interglacial samples were relatively diatom-rich, consequently counts of 400 specimens were possible. However, most glacial samples were diatom-poor, making it very difficult and time-consuming to count 400 specimens. Under these conditions, 10 transects were counted, as has been done in previous studies of sediments with very low diatom concentrations (Rebesco et al., 2014). Valves were only counted if greaster than 50% complete. Diatoms were identified to species level when possible (Crosta et al., 2005; Armand et al., 2005; Cefarelli et al., 2010). Occurrences of biostratigraphic markers were noted and tallied concurrently. Species were considered extinct when observed stratigraphically higher than extinction boundaries as identified by Cody et al. (2008). Station_core Longitude Latitude A005_KC02_PC01 115.623 -64.471 A006_KC03 115.043 -64.463 A042_KC14 116.6403 -64.5387 C012_KC04_PC05 119.3012 -64.675 C013_KC05 119.0183 -64.6538 C015_KC06 118.696 -64.729 C018_KC07 118.498 -64.401 C020_KC08 119.739 -64.794 C022_KC11 120.049 -65.1313 C025_KC12_PC08 120.8635 -64.9538 C038_KC13 119.1035 -64.4828 Armand, L.K., X. Crosta, O. Romero, J. J. Pichon (2005), The biogeography of major diatom taxa in Southern Ocean sediments: 1. Sea ice related species, Paleogeography, Paleoclimatology, Paleoecology, 223, 93-126. Cefarelli, A.O., M. E. Ferrario, G. O. Almandoz, A. G. Atencio, R. Akselman, M. Vernet (2010), Diversity of the diatom genus Fragilariopsis in the Argentine Sea and Antarctic waters: morphology, distribution and abundance, Polar Biology, 33(2), 1463-1484. Cody, R., R. H. Levy, D. M. Harwood, P. M. Sadler (2008), Thinking outside the zone: High-resolution quantitative diatom biochronology for the Antarctic Neogene, Palaeogeography, Palaeoclimatology, Palaeoecology, 260, 92-121, doi:10.1016/j.palaeo.2007.08.020 Crosta, X., O. Romero, L. K. Armand, J. Pichon (2005), The biogeography of major diatom taxa in Southern Ocean sediments: 2. Open ocean related species, Palaeogeography, Palaeoclimatology, Palaeoecology, 223, 66-92. Rebesco, M., E. Domack, F. Zgur, C. Lavoie, A. Leventer, S. Brachfeld, V. Willmott, G. Halverson, M. Truffer, T. Scambos, J. Smith, E. Pettit (2014), Boundary condition of grounding lines prior to collapse, Larson-B Ice Shelf, Antarctica, Science, 345, 1354-1358. Warnock, J. P., R. P. Scherer (2014), A revised method for determining the absolute abundance of diatoms, J. Paleolimnol., doi:10.1007/s10933-014-9808-0 These data were collected to provide paleoceanographic and biostratigraphic information. Amy Leventer, Isabel Dove, Meghan Duffy, and Meaghan Kendall unpublished data

Descriptions of piston core sections from the Sabrina Sea Floor Survey. Logs comprise descriptions of sediment lithologies down core with Munsell colors based on Munsell soil color chart.

Major element analyses of sediment in cores IN2017-V01-A005-PC01 and IN2017-V01-C012-PC05 collected using an Avaatech XRF scanner. Analyses taken every 50 mm. Piston cores were collected from the continental slope off the Sabrina Coast, seaward of the Totten Glacier. Cores were split, described and sampled for grain size, diatom assemblages and age dating. The archive half was then scammed using the Avaatech XRF scanner at Australian National University. The scanner works by analysing a spot every 5 cm down core for major elements using Xray Florescence to give an estimate of element abundance in counts per second. This can be converted into weight percent by analysing a calibration set of samples using other techniques (e.g. ICPMS) or to display the relative change in element abundances down core. The full suite of elements are obtained by 3 runs using different source energy levels. The files are labelled according to the energy level (in kv -kilovolts) of the source for 3 runs. Elements analysed in each run are: 10kv - Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Rh 30kv - Cu, Zn, Ga, Br, Rb, Sr, Y, Zr, Nb, Mo, Pb, Bi 50kv - Ag, Cd, Sn, Te, Ba.

Reconstructed sea spray and minerogenic data for a 12,000 year lake sediment record from Emerald Lake, Macquarie Island. Proxies are based on biological (diatoms) and geochemical (micro x-ray fluorescence and hyperspectral imaging) indicators. Data correspond to the figures in: Saunders et al. 2018 Holocene dynamics of the Southern Hemisphere westerly winds and possible links to CO2 outgassing. Nature Geoscience 11:650-655. doi.org/10.1038/s41561-018-0186-5. Detailed supplementary information: https://static-content.springer.com/esm/art%3A10.1038%2Fs41561-018-0186-5/MediaObjects/41561_2018_186_MOESM1_ESM.pdf Abstract: The Southern Hemisphere westerly winds (SHW) play an important role in regulating the capacity of the Southern Ocean carbon sink. They modulate upwelling of carbon-rich deep water and, with sea ice, determine the ocean surface area available for air–sea gas exchange. Some models indicate that the current strengthening and poleward shift of these winds will weaken the carbon sink. If correct, centennial- to millennial-scale reconstructions of the SHW intensity should be linked with past changes in atmospheric CO2, temperature and sea ice. Here we present a 12,300-year reconstruction of wind strength based on three independent proxies that track inputs of sea-salt aerosols and minerogenic particles accumulating in lake sediments on sub-Antarctic Macquarie Island. Between about 12.1 thousand years ago (ka) and 11.2 ka, and since about 7 ka, the wind intensities were above their long-term mean and corresponded with increasing atmospheric CO2. Conversely, from about 11.2 to 7.2 ka, the wind intensities were below their long-term mean and corresponded with decreasing atmospheric CO2. These observations are consistent with model inferences of enhanced SHW contributing to the long-term outgassing of CO2 from the Southern Ocean.