Abstract
The Last Interglacial (LIG: 130,000–115,000 years ago) was a period of warmer global mean temperatures and higher and more variable sea levels than the Holocene (11,700–0 years ago). Therefore, a better understanding of Antarctic ice-sheet dynamics during this interval would provide valuable insights for projecting sea-level change in future warming scenarios. Here we present a high-resolution record constraining ice-sheet changes in the Wilkes Subglacial Basin (WSB) of East Antarctica during the LIG, based on analysis of sediment provenance and an ice melt proxy in a marine sediment core retrieved from the Wilkes Land margin. Our sedimentary records, together with existing ice-core records, reveal dynamic fluctuations of the ice sheet in the WSB, with thinning, melting, and potentially retreat leading to ice loss during both early and late stages of the LIG. We suggest that such changes along the East Antarctic Ice Sheet margin may have contributed to fluctuating global sea levels during the LIG.
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Introduction
Global mean sea levels during the Last Interglacial (LIG) are thought to have reached ~6–9 m higher than present, with some records suggesting several peaks within that interval1,2,3,4,5,6,7,8,9. These elevated sea levels are attributed to a combination of ocean thermal expansion, melting of mountain glaciers, and mass loss from the Greenland and Antarctic ice sheets, with at least some contribution from Antarctica probably being required5,10,11,12. Furthermore, in order to explain the multiple sea-level peaks during the LIG, multiple events of ice-sheet mass loss must have occurred. However, detailed records of ice-sheet behaviour during the LIG are lacking, limiting our ability to independently test the proposed global mean sea-level fluctuations or to resolve their geographic origin. The East Antarctic Ice Sheet stores freshwater with a sea-level equivalent of ~53 m, of which ~19 m resides in marine-based subglacial basins, including the Wilkes, Aurora, and Recovery basins13. Because those marine-based sectors are considered to be vulnerable to ocean warming14, even small oceanographic changes in those regions could have contributed substantially to past fluctuations in global sea level. Whether ice in the marine-based subglacial basins of East Antarctica partially melted during the LIG is critical for understanding future sea-level changes14, but is not currently resolved by global sea-level records or by local sea-level fingerprints from this interval5,15. For this reason, a focus on sedimentary records from the East Antarctic margin is needed.
The ice sheet in the Wilkes Subglacial Basin (WSB) (Fig. 1) has received particular attention because its complete loss would raise global sea levels by ~3–4 m13,16. However, when and to what extent the ice-sheet margin in the WSB retreated during the LIG compared to its present position remains a matter of debate. A recent study using sediment provenance tracing in marine sediment core U1361A (64.40°S 143.88°E, 3465 m water depth, Fig. 1b) suggested a significant retreat of the ice-sheet margin in the WSB during several late Pleistocene interglacials, including the LIG17. Subsequent studies have argued for a more limited retreat in the WSB during the LIG18,19,20,21,22, but also suggest a major ice-sheet collapse during Marine Isotope Stage 11 at ~400 thousand years ago (ka)18. However, due to limitations in the chronologies and temporal resolution of existing records17,18, the timing and magnitude of ice-sheet change in the WSB during the LIG remain uncertain.
To better constrain the ice-sheet behaviour in the WSB during the LIG, we generated high-resolution records (300-year resolution) of detrital neodymium (Nd) isotopes and iceberg rafted debris (IBRD), supported by authigenic beryllium (Be) isotopes, in marine sediment core GC1407 (63.75°S, 130.52°E, 3687 m water depth, Fig. 1b). This core was retrieved during a survey of the Antarctic Geological and Geophysical Research Project by the Japan National Oil Corporation in 1993. Neodymium isotope ratios are expressed as εNd values, the deviation of 143Nd/144Nd ratios from the Chondritic Uniform Reservoir value in parts per 10,000, and provide evidence on the locus of subglacial erosion17 (see Methods). Authigenic Be isotope ratios are reported as 10Be/9Be ratios and are considered to be an indicator of meltwater inputs23,24,25 (see Methods). In addition, to evaluate the extent of ice-sheet margin retreat in the WSB, we estimated changes in elevation at Talos Dome during the LIG based on the reported oxygen isotope (δ18O) records in Antarctic ice cores22. The chronologies for marine sediment cores GC1407 and U1361A are tuned to the Antarctic Ice Core Chronology 2012 (AICC2012)26,27, based on the onset and end of the LIG (see Methods).
Results and discussion
Two episodes of provenance change during the LIG
Detrital sediment Nd isotopes have been widely applied as an indicator of sediment provenance around Antarctica17,28,29,30. The detrital record of fine-grained sediment (<63 µm) in core GC1407 shows relatively low εNd values (around −16 to −15) during the Holocene and relatively higher values with more variability (−17 to −13) during the LIG (Fig. 2d, i). Two episodic increases in εNd values (reaching −14 to −13) are recognised within the LIG (129–126 ka and 122–118 ka) (Fig. 2i), suggesting dynamic changes in sediment provenance. Interestingly, the updated age model for core U1361A also reveals some evidence for two Nd isotope peaks during the LIG in core U1361A, although they are defined by only a small number of data points (Fig. 2i). Given the good agreement in the timing of the two peaks between the two cores, our high-resolution record from core GC1407 appears to reinforce the presence of two peaks in core U1361A. Although there is a clear offset of ~4 εNd units between the two records (Fig. 2d, i), the similarity in terms of the magnitude of changes and temporal patterns suggests that the two events of increasing εNd values during the LIG likely reflect the same phenomenon of provenance change.
Sediment provenance variations indicated by the Nd isotope record in core U1361A are thought to reflect the waxing and waning of the ice-sheet margin in the WSB17.This interpretation is based upon the ultimate source of detrital sediment input to marine sequences on the Antarctic margin being from the erosion of proximal and/or upstream coastal bedrock31,32,33,34,35,36, which can be expected to change with advance or retreat of the ice-sheet margin. Furthermore, the εNd values of the bedrock vary by region17,28,29,30 (Fig. 1b). The coastal bedrock in the vicinity of core GC1407 (Adelie Coast; around 145–135°E) has εNd values of −19 to −26 (Archaean and Proterozoic age), while coastal bedrock proximal to core U1361A (George V Coast; around 150–160°E) has εNd values of −12 to −18 (Lower Palaeozoic age)30. In contrast, εNd values in the WSB, inland of George V Coast, are inferred to be more radiogenic (−4 to −7), reflecting the Permian-Cretaceous rocks of the Ferrar Large Igneous Province (FLIP) and associated Beacon Supergroup30,37. At present, detrital sediments are dominantly transported from the coastal margin of the WSB to the location of core U1361A17. Since the LIG was also an interglacial climate state, it can be assumed that the sediment transport regime during the LIG was broadly similar to the modern day. Therefore, the high εNd values in core U1361A during the LIG (Fig. 2i) are interpreted to reflect the supply of detritus from inland bedrock to the continental rise due to WSB ice-sheet retreat17.
Since sediments are transported westwards by bottom currents (Antarctic Bottom Water)35,36 near Wilkes Land, the detrital Nd isotope record in core GC1407 likely reflects the erosion of coastal bedrock upstream of the site (i.e., Adelie Coast and George V Coast) (Fig. 1b), especially during interglacials when the bottom current intensified35,36 (see Methods). If retreat of the ice-sheet margin in the WSB enhanced the supply of sediments from inland FLIP sources, relatively high detrital εNd values would also be expected in core GC1407, whereas the supply of detritus from the Adelie Coast would result in a lowering of εNd values. As such, we suggest that the relatively low εNd values in core GC1407 compared to core U1361A (~4 εNd units offset) probably indicate continuous detrital input from the Adelie Coast through the Holocene and LIG (Fig. 2d, i). On the other hand, we suggest that the two Nd isotope peaks observed in core GC1407 during the LIG, coincident with peaks in core U1361A, reflect ice-sheet margin retreat events in the WSB. Overall, our new high-resolution record, together with improved constraints on the chronology of core U1361A, reveals that ice-sheet margin retreat in the WSB occurred during both the early and late LIG. Although our record does not rule out the possibility of ice-sheet margin retreat in the Adelie Coast region, several independent ice-sheet modelling studies suggest that ice-sheet margin retreat in this region would have been limited during the LIG14,19 (Fig. 1b), which is also consistent with observations over recent decades from the Adelie Coast38.
Extent of ice-sheet melting in the WSB
To provide further evidence on the nature and magnitude of ice-sheet margin changes in the WSB that are implied by the two peaks in the detrital Nd isotope record, we measured authigenic Be isotopes in core GC1407. Changes in the 10Be/9Be ratio in marine sediments proximal to ice-sheet margins can be used to infer regional inputs from ice melt23,24,25. The production of 10Be in the atmosphere is followed by its deposition onto the ocean and ice sheets, such that the melting of ice sheets and icebergs releases the accumulated 10Be into the ocean, where it is scavenged by particles and accumulates in the authigenic fraction of marine sediments23. In contrast, 9Be is the stable naturally-occurring isotope found in bedrock and supplied via erosion and weathering. An increase in the 10Be/9Be ratio in marine sediments can therefore be interpreted as indicating a significant ice melting event23 (see Methods).
The 10Be/9Be record in core GC1407 provides strong support for ice mass loss from the WSB during the LIG. The 10Be/9Be ratios vary from 6.0 × 10−9 to 9.1 × 10−9 during the LIG, with a two-stepped increase leading to maximum values at ~120 ka (Fig. 2h). This finding points to an increase in ice melting during the late LIG, and suggests that melting was more pronounced from 122–118 ka than from 129–126 ka. The two-stepped increase in 10Be/9Be ratios also coincides with the Nd isotope peaks (Fig. 2h, i), supporting the interpretation of those provenance shifts as reflecting ice-sheet retreat rather than reflecting changes in other processes such as deep-current sediment transport.
The content of iceberg rafted debris (IBRD; weight percent of grains of 250 µm–2 mm diameter), which provides a qualitative indicator of iceberg discharge17, was also measured in core GC1407 to infer the causes of ice mass loss from the WSB. Peaks in IBRD in cores GC1407 and U1361 are observed during the early LIG and coincide in timing (Fig. 2j), which suggests that iceberg calving was an important process for ice mass loss during the early LIG. On the other hand, the 10Be/9Be record reaches its maximum during the late LIG, indicating that ice-shelf basal melting23 may have played a relatively more important role than calving in ice mass loss from the WSB during the late LIG.
Assessment of ice mass loss in the WSB
To further evaluate the ice-sheet retreat in the WSB during the late LIG as indicated by our sedimentary records, we made a comparison to the δ18O records from the Talos Dome and EPICA Dome C (EDC) ice cores39. Differences in the δ18O records between the Talos Dome and EDC ice cores have been proposed to provide an indicator for the advance and retreat of the ice-sheet margin in the WSB19,22. Because the Talos Dome site is located in the headlands of the WSB outflow region, it is sensitive to changes of the ice-sheet margin in the WSB19,22, unlike inland plateau sites such as EDC (Fig. 1b). Therefore, the δ18O record from the Talos Dome ice core has been used to estimate temperature increases that were associated with ice-sheet elevation drops, which can be linked to regional ice-sheet mass loss19,21,22,40,41,42.
During the early LIG (130–126 ka), the δ18O records at the Talos Dome and EDC sites vary in parallel (Fig. 2f, g). In contrast, the δ18O record at the Talos Dome increases by 1.5‰ from 126 ka to 118 ka, whereas the EDC record shows the opposite trend with a decrease during this period (Fig. 2f, g)39. The increase in the δ18O record at Talos Dome compared to that of EDC is interpreted as a site temperature increase caused by a decrease in site elevation22. Notably, the 1.5‰ increase in δ18O values at Talos Dome during the late LIG coincides with the increases in εNd values and 10Be/9Be ratios in cores GC1407 and U1361 (Fig. 2). This temporal agreement allows us to link ice thinning at the Talos Dome site to ice-sheet margin retreat and melting in the WSB, as inferred from the offshore records. The timing of these changes in the ice core record further supports the hypothesis that ice-sheet retreat and melting may have been more pronounced during the late LIG (122–118 ka) than during the early LIG (129–126 ka).
Following Crotti et al. (2022)22, we estimate the change in elevation at Talos Dome during the LIG by applying three different δ18O-elevation relationships derived from climate simulations and observations (−0.53‰/100 m, –0.93‰/100 m, and −1.35‰/100 m)21,22,43,44. Based on those three different relationships, the 1.5‰ increase in δ18O values at Talos Dome is equivalent to a drop in local ice-sheet surface elevation of 111–283 m. Although their study focused on the early LIG, Sutter et al. (2020)19 presented a model in which the elevation drop of 100–200 m at Talos Dome could be related to an inland retreat of the ice margin in the WSB by several hundred km (their experiment with 8-km resolution, 300-year perturbation)19 (black line in Fig. 1b). Another recent model presented by Crotti et al. (2022)22 also indicates ice margin retreat in the WSB of ~100 km during the 133–115 ka interval, and notably the greatest retreat occurred towards the end of the LIG, which is consistent with our interpretations. In summary, the above findings provide multiple lines of evidence from which we infer ice mass loss from the WSB during the late LIG from 122–118 ka.
Drivers of ice mass loss in the WSB
Previous studies of Antarctic ice-sheet variations during the LIG have focused on the early LIG (~128 ka) when air temperature rise in Antarctica reached its peak19,21. However, our records reveal evidence for extensive ice mass loss from the WSB during the late LIG (~120 ka), when air temperatures were comparable to the present (Fig. 3a). Hence, atmospheric forcing was unlikely to have been a trigger for ice mass loss during the late LIG. Instead, since the ice sheet in the WSB is marine-based13, ocean forcing from changes in ocean circulation and/or ocean warming may have played critical roles in the ice-sheet mass loss during the late LIG.
In general, the LIG was characterised by sea surface temperatures (SST) in the Southern Ocean that were approximately 2 °C warmer than the pre-industrial Holocene45 and by a southward-shifted Polar Front in the Indian Ocean46. Both these conditions could have contributed to enhanced ocean forcing of ice-sheet mass loss, with the frontal shifts potentially helping to drive incursions of relatively warm Circumpolar Deep Water onto the continental shelves, which could lead to inland migration of grounding lines47,48. Notably, deep-ocean temperatures in the Southern Ocean also remained at elevated values from the early to the late LIG49 (Fig. 3b), pointing to warmer than present conditions in the sub-surface Southern Ocean even during the late LIG. Furthermore, while the spatial coverage is sparse, two marked warming peaks can be resolved in some SST reconstructions from the Southern Ocean, with one during the early LIG and another during the late LIG50,51 (Fig. 3c). Although the above records are from lower latitudes of the Southern Ocean than the Antarctic margin, recent diatom-based SST reconstructions from close to the margin also indicate warmer conditions throughout the LIG than today46. Overall, these records are consistent with ocean forcing as the primary driver of ice loss from the ice sheet in the WSB during the LIG, although the exact mechanisms responsible for the ocean warming remain to be fully explored.
Contribution of ice loss from the WSB to global sea-level rise
Our data provide a unique opportunity to compare a well-resolved ice-proximal record of changes in the East Antarctic Ice Sheet to global sea-level records for this interglacial period (Fig. 4)1,2,3,4,5,6,7,8,9. Sea-level variability during the LIG remains uncertain, but three broad scenarios have been proposed: (1) a high-stand during the early LIG8,9; (2) a high-stand for the initial several thousand years followed by a secondary rise around 120 ka1,6; and (3) bimodal sea-level peaks during the early and late LIG2,3,4 (Fig. 4a–c). Recent studies have suggested that parts of the West Antarctic Ice Sheet were lost during the early LIG and could have made the main contribution to global sea-level rise at that time20,52. However, the causes of a possible sea-level rise during the late LIG for scenarios 2 and 3 remain unknown. Our study provides evidence for ice mass loss from the WSB during the late LIG, thereby supporting an Antarctic origin for global sea-level rise at this time, which would be consistent with sea-level rise scenarios 2 and 3. Taken together with previous studies11,52, we suggest that ice sheets in different regions of Antarctica lost ice mass in a step-wise pattern during the LIG, which may have contributed to dynamic fluctuations of global sea level in any of the scenarios 1–3 during the LIG.
Ice-sheet model experiments19,22 indicate that a 100–200 m drop in elevation at Talos Dome due to WSB ice-sheet margin retreat would translate to a sea-level rise of ~0.4–0.8 m. Combining those model results with our study, we suggest that ice-sheet mass loss in the WSB probably contributed to a similar magnitude of sea-level rise during the late LIG. Hence, such a change could only explain a small portion of the global sea-level rise of ~6–9 m estimated for the LIG5. If the global sea-level rise was closer to the maximum estimates (~9 m)5, then significant ice mass loss from other sectors of East Antarctica would still be required, after accounting for contributions from mass loss of the marine-based West Antarctic Ice Sheet (~3.3 m) and a portion of the Greenland Ice Sheet (likely up to ~2 m)11,53,54,55. Within East Antarctica, the ice sheets in the Aurora and Recovery Subglacial Basins (Fig. 1a) are also thought to be vulnerable to ocean warming56,57, and represent likely candidates for additional global sea-level rise during the LIG. Comparable high-resolution records from the different sectors of the East Antarctic Ice Sheet will therefore be required to better constrain the ice-sheet dynamics and the origin of sea-level variability during the LIG.
Methods
Material
Gravity core GC1407 was collected from the continental rise offshore of Wilkes Land (63.75°S, 130.52°E, 3687 m water depth) (Fig. 1) during a survey of the Antarctic Geological and Geophysical Research Project (FY1993) by the Japan National Oil Corporation. The total length of core GC1407 is 5.35 m. Glacial-interglacial cycles are well resolved in the core, with glacial intervals indicated by silty-clay with occasional laminations, and interglacial intervals marked by siliceous silty-clay with high SiO2 content.
Detrital neodymium isotope measurements
To measure detrital Nd isotopes in core GC1407, ~200 mg of the bulk fine-grained (<63 µm) sediment fraction was first leached by sequential leaching methods58. The Fe-Mn oxide fraction was leached using 0.05 M hydroxylamine hydrochloride (HH) in 25% acetic acid (Ultrapure from Kanto Chemical Co., INC., Tokyo, Japan) in a water bath at 85 °C for four hours. Opal was then leached using 1 M NaOH in a water bath at 80 °C for 30 min. After those procedures, the leached samples were rinsed in ultrapure water three times and dried in an oven (50 °C) for ~24 h. Then, ~60 mg samples were completely digested with HNO3-HF-HClO4 at 130 °C for at least one day.
Chemical separation of Nd was carried out as follows: (i) major elements were removed from the sample solution using a cation exchange resin column (MCI GEL CK08P, Mitsubishi Chemical Corporation) with 1.8 M HCl; (ii) the REE fraction was extracted using 4.5 M HCl eluent; and (iii) the Nd fraction was isolated using a Ln-spec resin column (50–100 µm, Eichrom Technologies) with 0.25 M HCl eluent. All reagents were trace metal grade reagents (TAMAPURE-AA-100 from Tama Chemicals, Ltd., Tokyo, Japan) and all procedures were conducted in a clean laboratory at the University of Toyama.
Samples were then dissolved in 0.16 M or 0.1 M HNO3 and ultrasonicated for 1 h prior to analysis using either a first generation (Nu Plasma) or second generation (Nu Plasma II) Nu Instruments HR MC-ICP-MS in the MAGIC laboratories at Imperial College London. The sample introduction system consisted of a Glass Expansion MicroMist nebuliser (typical uptake rate ~100 µL/min) connected to a DSN-100 desolvation nebuliser system. Measurements consisted of 50 cycles. All Nd isotope ratios were corrected for instrumental mass bias using the exponential law and a 146Nd/144Nd ratio of 0.7219. The reported 143Nd/144Nd ratios were corrected to a JNdi-1 143Nd/144Nd ratio of 0.512115 (ref. 59) using bracketing standards. A correction for 144Sm interference was applied, but all samples fell significantly below the threshold for accurate correction of 144Sm on the 144Nd signal (i.e. <1000 ppm). The external reproducibility of sample data was estimated from the within-session standard deviation (2 s.d.) of the JNdi-1 standards, while its accuracy is demonstrated by repeat analyses of rock standard BCR-2, which yielded 143Nd/144Nd = 0.512641 ± 0.000015 (n = 16), in excellent agreement with the literature value60.
Sortable silt measurements
In preparation for grain-size analysis61, carbonate and biogenic silica were removed from sediment samples by reacting with 1 M acetic acid for 24 h, followed by heating to 85 °C in 2 M sodium carbonate for 5 h, with samples being agitated several times during each step. Samples were then suspended in 0.2% sodium diphosphate decahydrate solution and placed on a rotating wheel before analysis using a laser diffraction-scattering particle size analyser (Horiba LA-920). Repeated analysis was performed on a subset of samples in an arbitrary order over several days and the mean standard deviation of replicate analyses was ±0.1 µm.
Neodymium isotope records in core GC1407 as a provenance tracer
The detrital Nd isotope record in core GC1407 (<63 µm fraction) shows large variations in εNd values from −17 to −13 during the last glacial-interglacial cycle (Supplementary Fig. 1b). In general, relatively low values were recorded during interglacial periods, with higher values during glacial periods. Fine-grained sediment (<63 µm) at Antarctic continental rise sites such as GC1407 is predominantly composed of contourite and turbidite deposits (e.g., ref. 32). Therefore, the long-term glacial-interglacial trends in Nd isotopes probably reflect changes in the relative contribution of detrital sources among contourites and turbidites.
The contourites are supplied from the upstream region by the bottom water current. In core GC1407, the mean grain size of the sortable silt fraction (10–63 µm) (\(\overline{{{{{{\rm{SS}}}}}}}\)), which is indicative of bottom water current intensity61, shows large glacial-interglacial variations, with finer grain size during glacials and coarser grain size during interglacials (Supplementary Fig. 1). This observation suggests that bottom current flow was intensified during the interglacial periods, which would have led to enhanced contourite supply from the upstream region. Furthermore, the absence of turbidite layers in core GC1407 during the LIG suggests that contourites were the predominant source throughout the LIG. Therefore, the fluctuations of detrital Nd isotope composition during the LIG should reflect changes in the sediment provenance upstream of the site.
Iceberg rafted debris (IBRD) measurements
Samples were processed for grain size analysis at Hokkaido University to provide evidence on the IBRD content. Dried samples were weighed and then wet-sieved to recover the coarse sand fraction (percent 250 µm–2 mm), which has previously been used to indicate IBRD in Antarctic studies17. The 250 µm–2 mm fraction was weighed to obtain a weight percent of IBRD (percent 250 µm–2 mm) relative to the bulk sediment. For this study, we did not calculate IBRD mass accumulation rates, but they would scale almost directly with the weight percent IBRD (since our age model assumes constant sedimentation rates in the LIG and there are no large shifts or trends in dry bulk density in this interval).
Cycladophora davisiana relative abundance counts
Freeze-dried subsamples were weighed (approximately 1–2 g) and then treated with 15% H2O2 to remove the organic matter, followed by treatment with HCl solution to remove the calcium carbonate. The samples were then wet sieved (45 µm mesh size), after which two types of permanent slides were made from the residue to quantify the abundance (Q-slide) and for faunal analysis (F-slide)62. Briefly, to prepare the Q-slides, all residues were transferred to a 200 mL beaker containing 100 mL of distilled water. The solution was then well mixed, after which a 500 μL sample was taken from the suspension using a micropipette and dropped onto a glass slide. The sample was then dried and mounted with Norland optical adhesive. The F-slides were made from the remaining residues in the beaker and then mounted with Norland. On average, 100 individuals were counted on each slide, and the abundance of C. davisiana is reported in percent as the number per 100 individuals.
XRF core-scanning measurements
The SiO2 content was analysed by X-ray fluorescence (XRF) analysis of slab samples conducted at 1-cm intervals using the TATSCAN-F263 at Kochi University. Samples were wrapped in thin prolene film and scanned with a scanning diameter of 1 cm.
Authigenic beryllium isotope measurements
Samples for Be isotope analysis were prepared at the National Institute of Polar Research according to the chemical procedure established by ref. 64 and revised by ref. 65. Authigenic Be was extracted from 2 g dry samples by soaking them in 20 ml of leaching solution (0.04 M hydroxylamine hydrochloride and 25% acetic acid) at 95 ± 5 °C for 6 h. A 2 ml aliquot of the resulting leachate was sampled for measurement of the natural 9Be concentration using inductively coupled plasma mass spectrometry (ICP-MS). The remaining solution was spiked with 300 µl of 9Be carrier (9.833 × 10−4 g/g 9Be) before Be purification by chromatography in order to determine accurate 10Be concentrations using accelerator mass spectrometer (AMS) measurements of 10Be/9Be ratios at Micro Analysis Laboratory, Tandem accelerator, University of Tokyo (MALT)66,67. Sample 10Be concentrations were calculated from the 10Be/9Be ratios normalized to the KN standard with a nominal 10Be/9Be ratio of 8.56 × 10−12 (ref. 68), and the reported authigenic 10Be concentrations were decay-corrected using the 10Be half-life of 1.387 ± 0.012 Ma69,70. Uncertainties on the authigenic 10Be/9Be ratios were calculated by propagating the uncertainties on the ICP-MS and AMS measurements.
Use of beryllium isotopes in core GC1407 as a meltwater proxy
Beryllium isotopes have been used as tracers in various fields of earth sciences, providing proxies for geomagnetic field strength65, sea-ice extent, ice-shelf coverage25,71, and freshwater discharge from melting ice23,65. Cosmogenic 10Be is produced in the upper atmosphere by the interaction of cosmic rays and is globally homogenised, with an atmospheric residence time of 1–2 years, before being deposited as meteoric 10Be on the Earth surface72. Although cosmic rays also interact with surface rocks and produce in-situ 10Be, the production rates for this process are orders of magnitude lower than for meteoric 10Be. In contrast, stable 9Be occurs naturally as a trace component of crustal rocks and is transported by glacial erosion and weathering to the Antarctic coastal margin25. Therefore, 10Be/9Be ratios can be applied in Antarctic margin sediments to constrain sedimentary processes and paleoenvironments, including freshwater supply during events of large-scale ice-sheet retreat. Since using the 10Be/9Be ratio corrects for variations related to particle size, retention behaviour, and dilution, this ratio has been proposed as a more effective meltwater proxy than using 10Be concentrations alone23,24,25.
Authigenic 10Be and 9Be concentrations in core GC1407 show similar long-term changes, with higher values during interglacial periods (Holocene and LIG) and lower values during glacial periods (Marine Isotope Stages 2 and 6) (Supplementary Fig. 2). Most notably, authigenic 10Be concentrations during glacial periods decrease to ~10% of their value during interglacial periods, indicating a glacial-interglacial climate modulation of the records rather than a geomagnetic control23,65. Because the area of sea-ice cover changed significantly through glacial-interglacial cycles, the major decrease in 10Be inputs during glacial periods likely reflects expanded and/or more permanent sea-ice coverage or the presence of ice shelves over the site. In contrast, variations in authigenic 10Be inputs within interglacial periods cannot be attributed to sea-ice changes because the site of core GC1407 was not covered by sea ice (or ice shelves) during the LIG73. Hence, the 10Be and 10Be/9Be variations in core GC1407 during the LIG likely reflect variations in the excess supply of 10Be to this region via freshwater input from melting ice. Rapid scavenging by particles in the upper water column would transport the 10Be to depth, enabling it to accumulate in the authigenic fraction of the marine sediments. Although other factors such as the scavenging of 10Be by biogenic opal could potentially influence the deep-ocean sedimentary record of 10Be, the SiO2 content in core GC1407 does not show significant fluctuations during the LIG (Supplementary Fig. 3d), which suggests that any such effect is probably limited in core GC1407. Hence, similar to previous studies (e.g., refs. 23,65), we use the authigenic 10Be/9Be record in core GC1407 as an indicator of regional freshwater inputs from melting ice.
Correlation between marine sediment cores
Benthic foraminiferal δ18O records have been extensively applied to determine chronologies for marine sediment sequences, but benthic foraminifera are not continuously preserved in cores GC1407 or U1361A. Therefore, we have identified the interval of the LIG in cores GC1407 and U1361A based on records of C. davisiana and productivity that have previously been used to determine chronologies in the Southern Ocean (e.g., refs. 74,75).
First, we identified the interval of the LIG in core GC1407 based on the correlation of C. davisiana stratigraphy between cores GC1407 and RC11-120 (43.52°S, 79.87°E; 3135 m), since the chronology of RC11-120 has been well constrained using its planktonic foraminiferal (Globigerina bulloides) δ18O record76,77 (Supplementary Figs. 3 and 4). The relative abundance of C. davisiana fluctuates through glacial-interglacial cycles, with high contents during interglacials and low contents during glacials in most of the Southern Ocean74,78. As shown in Supplementary Fig. 3, temporal variations of C. davisiana in cores GC1407 and RC11-120 are similar over the last 140 kyr, which provides two tie points for core GC1407 near the start and end of the LIG (Supplementary Data).
Second, the LIG interval in core U1361A was constrained based on correlation of the productivity records from cores U1361A17 and GC1407. In the Southern Ocean, the glacial-interglacial productivity pattern depends on latitude, with low and high productivity during glacial and interglacial periods, respectively, in the high latitudes of the Indian sector of the Southern Ocean75. Given the proximity of cores GC1407 and U1361A, their productivity patterns are expected to be similar through time. Indeed, the SiO2 content in core GC1407 and Ba/Al ratios in core U1361A (proposed as a productivity proxy in the study area17) show similar patterns on orbital to millennial timescales, including during the LIG interval (Supplementary Figs. 3 and 4). The chronology of core U1361A was therefore aligned with core GC1407 at two tie points based on their productivity records (Supplementary Figs. 3 and 4 and Supplementary Data).
Age control for marine sediment cores and ice cores
To compare the marine sediment core and ice core data, we transferred the Antarctic Ice Core Chronology 2012 (AICC2012)26,27 to the marine sediment core records. Recent studies have proposed that the correlation between sea surface temperature (SST) in the Southern Ocean and air temperature proxies (δD or δ18O) in the Antarctic ice cores can be used to tune the age scales of marine sediment cores, including during the LIG when there is a strong similarity between the marine and ice core records50,79. However, SST records are not available for cores GC1407 or U1361A. Therefore, the planktonic foraminiferal δ18O record in core RC11-120, which is taken as an indicator of SST, and the δD record from the Dome Fuji ice core80 were compared in order to transfer the age of core RC11-120 onto the AICC2012 age scale, using three tie points (Supplementary Fig. 4, Supplementary Data). Then, this chronology was transferred to core GC1407 based on the correlation of the C. davisiana records between cores RC11-120 and GC1407, as described above. Finally, this chronology was transferred to core U1361A based on the correlation between the productivity records from cores GC1407 and U1361A, as also described above. With these age models, the 2.8–3.8 m depth interval in core GC1407 and the 1.4–2.1 m depth interval in core U1361A correspond approximately to the LIG (Supplementary Fig. 3). The robustness of the chronology for core GC1407 is also supported by the last appearance of the diatom Hemidiscus karstenii, which is identified at 4 m depth in this core, and is known to occur within late Marine Isotope Stage 650. Note that these age models imply significantly higher sedimentation rates during the LIG than during the glacial intervals (around 3.5 to 5 times higher) (Supplementary Fig. 5), and that the age model for core U1361A is significantly different during the LIG from the original published version (which had limited constraints and assumed linear sedimentation rates throughout the late Pleistocene).
References
Blanchon, P., Eisenhauer, A., Fietzke, J. & Liebetrau, V. Rapid sea-level rise and reef back-stepping at the close of the last interglacial highstand. Nature 458, 881–884 (2009).
Kopp, R. E., Simons, F. J., Mitrovica, J. X., Maloof, A. C. & Oppenheimer, M. Probabilistic assessment of sea level during the last interglacial stage. Nature 462, 863–867 (2009).
Thompson, W. G., Curran, A. H., Wilson, M. A. & White, B. Sea-level oscillations during the last interglacial highstand recorded by Bahamas corals. Nat. Geosci. 4, 684–687 (2011).
O’Leary, M. J. et al. Ice sheet collapse following a prolonged period of stable sea level during the last interglacial. Nat. Geosci. 6, 796–800 (2013).
Dutton, A. et al. Sea-level rise due to polar ice-sheet mass loss during past warm periods. Science 349, aaa4019 (2015).
Dutton, A., Webster, J. M., Zwartz, D., Lambeck, K. & Wohlfarth, B. Tropical tales of polar ice: evidence of Last Interglacial polar ice-sheet retreat recorded by fossil reefs of the granitic Seychelles islands. Quat. Sci. Rev. 107, 182–196 (2015).
Barlow, N. L. M. et al. Lack of evidence for a substantial sea-level fluctuation within the Last Interglacial. Nat. Geosci. 11, 627–634 (2018).
Polyak, V. J. et al. A highly resolved record of relative sea level in the western Mediterranean Sea during the last interglacial period. Nat. Geosci. 11, 860–864 (2018).
Rohling, E. J. et al. Asynchronous Antarctic and Greenland ice-volume contributions to the last interglacial sea-level highstand. Nat. Commun. 10, 1–9 (2019).
McKay, N. P., Overpeck, J. T. & Otto-Bliesner, B. L. The role of ocean thermal expansion in Last Interglacial sea level rise. Geophys. Res. Lett. 38, 4–9 (2011).
Dahl-Jensen, D. et al. Eemian interglacial reconstructed from a Greenland folded ice core. Nature 493, 489–494 (2013).
Shackleton, S. et al. Global ocean heat content in the Last Interglacial. Nat. Geosci. 13, 77–81 (2020).
Fretwell, P. et al. Bedmap2: improved ice bed, surface and thickness datasets for Antarctica. Cryosphere 7, 375–393 (2013).
DeConto, R. M. & Pollard, D. Contribution of Antarctica to past and future sea-level rise. Nature 531, 591–597 (2016).
Hay, C. et al. The sea-level fingerprints of ice-sheet collapse during interglacial periods. Quat. Sci. Rev. 87, 60–69 (2014).
Mengel, M. & Levermann, A. Ice plug prevents irreversible discharge from East Antarctica. Nat. Clim. Change 4, 451–455 (2014).
Wilson, D. J. et al. Ice loss from the East Antarctic Ice Sheet during late Pleistocene interglacials. Nature 561, 383–386 (2018).
Blackburn, T. et al. Ice retreat in Wilkes Basin of East Antarctica during a warm interglacial. Nature 583, 554–559 (2020).
Sutter, J. et al. Limited retreat of the Wilkes Basin ice sheet during the Last Interglacial. Geophys. Res. Lett. 47, e2020GL088131 (2020).
Golledge, N. R. et al. Retreat of the Antarctic Ice Sheet during the Last Interglaciation and implications for future change. Geophys. Res. Lett. 48, e2021GL094513 (2021).
Goursaud, S. et al. Antarctic Ice Sheet elevation impacts on water isotope records during the Last Interglacial. Geophys. Res. Lett. 48, e2020GL091412 (2020).
Crotti, I. et al. Wilkes subglacial basin ice sheet response to Southern Ocean warming during late Pleistocene interglacials. Nat. Commun. 13, 1–11 (2022).
Valletta, R. D., Willenbring, J. K., Passchier, S. & Elmi, C. 10Be/9Be ratios reflect Antarctic Ice Sheet freshwater discharge during Pliocene warming. Paleoceanogr. Paleoclimatol. 33, 934–944 (2018).
Behrens, B., Miyairi, Y., Sproson, A. D., Yamane, M. & Yokoyama, Y. Meltwater discharge during the Holocene from the Wilkes subglacial basin revealed by beryllium isotope analysis of marine sediments. J. Quat. Sci. 34, 603–608 (2019).
White, D. A. et al. Beryllium isotope signatures of ice shelves and sub-ice shelf circulation. Earth Planet. Sci. Lett. 505, 86–95 (2019).
Bazin, L. et al. An optimized multi-proxy, multi-site Antarctic ice and gas orbital chronology (AICC2012): 120-800 ka. Climate 9, 1715–1731 (2013).
Veres, D. et al. The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years. Climate 9, 1733–1748 (2013).
Cook, C. P. et al. Dynamic behavior of the East Antarctic ice sheet during Pliocene warmth. Nat. Geosci. 6, 765–769 (2013).
Roy, M., van de Flierdt, T., Hemming, S. R. & Goldstein, S. L. 40Ar/39Ar ages of hornblende grains and bulk Sm/Nd isotopes of circum-Antarctic glacio-marine sediments: Implications for sediment provenance in the southern ocean. Chem. Geol. 244, 507–519 (2007).
Pierce, E. L. et al. Evidence for a dynamic East Antarctic ice sheet during the mid-Miocene climate transition. Earth Planet. Sci. Lett. 478, 1–13 (2017).
Licht, K. J. & Hemming, S. R. Analysis of Antarctic glacigenic sediment provenance through geochemical and petrologic applications. Quat. Sci. Rev. 164, 1–24 (2017).
Wu, L. et al. Late Quaternary deep stratification-climate coupling in the Southern Ocean: Implications for changes in abyssal carbon storage. Geochem. Geophys. Geosyst. 19, 379–395 (2018).
Escutia, C., Brinkhuis, H., Klaus, A. & the Expedition 318 Scientists Proc. IODP, 318 (Integrated Ocean Drilling Program Management International, Inc., Tokyo, 2011).
Donda, F., Brancolini, G., De Santis, L. & Trincardi, F. Seismic facies and sedimentary processes on the continental rise off Wilkes Land (East Antarctica): evidence of bottom current activity. Deep Sea Res. Part II Top. Stud. Oceanogr. 50, 1509–1527 (2003).
Presti, M. et al. Sediment delivery and depositional patterns off Adelie Land (East Antarctica) in relation to late Quaternary climatic cycles. Mar. Geol. 284, 96–113 (2011).
Jimenez-Espejo, F. J. et al. Late Pleistocene oceanographic and depositional variations along the Wilkes Land margin (East Antarctica) reconstructed with geochemical proxies in deep-sea sediments. Glob. Planet Change 184, 103045 (2020).
Ferraccioli, F., Armadillo, E., Jordan, T., Bozzo, E. & Corr, H. Aeromagnetic exploration over the East Antarctic Ice Sheet: a new view of the Wilkes Subglacial Basin. Tectonophysics 478, 62–77 (2009).
Rignot, E. et al. Four decades of Antarctic Ice Sheet mass balance from 1979–2017. Proc. Natl Acad. Sci. USA 116, 1095–1103 (2019).
Masson-Delmotte, V. et al. A comparison of the present and last interglacial periods in six Antarctic ice cores. Climate 7, 397–423 (2011).
Fogwill, C. J. et al. Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the Last Glacial Termination. Sci. Rep. 7, 1–10 (2017).
Weber, M. E., Golledge, N. R., Fogwill, C. J., Turney, C. S. M. & Thomas, Z. A. Decadal-scale onset and termination of Antarctic ice-mass loss during the last deglaciation. Nat. Commun. 12, 1–13 (2021).
Sutter, J. et al. Modelling the Antarctic Ice Sheet across the mid-Pleistocene transition – Implications for Oldest Ice. Cryosphere 13, 2023–2041 (2019).
Frezzotti, M. et al. Geophysical survey at Talos Dome, East Antarctica: The search for a new deep-drilling site. Ann. Glaciol. 39, 423–432 (2004).
Werner, M., Jouzel, J., Masson-Delmotte, V. & Lohmann, G. Reconciling glacial Antarctic water stable isotopes with ice sheet topography and the isotopic paleothermometer. Nat. Commun. 9, 1–10 (2018).
Capron, E. et al. Temporal and spatial structure of multi-millennial temperature changes at high latitudes during the Last Interglacial. Quat. Sci. Rev. 103, 116–133 (2014).
Chadwick, M., Allen, C. S., Sime, L. C., Crosta, X. & Hillenbrand, C. D. How does the Southern Ocean palaeoenvironment during Marine Isotope Stage 5e compare to the modern? Mar. Micropaleontol. 170, 102066 (2022).
Pritchard, H. D. et al. Antarctic ice-sheet loss driven by basal melting of ice shelves. Nature 484, 502–505 (2012).
Fogwill, C. J. et al. Testing the sensitivity of the East Antarctic Ice Sheet to Southern Ocean dynamics: past changes and future implications. J. Quat. Sci. 29, 91–98 (2014).
Elderfield, H. et al. A record of bottom water temperature and seawater δ18O for the Southern Ocean over the past 440 kyr based on Mg/Ca of benthic foraminiferal Uvigerina spp. Quat. Sci. Rev. 29, 160–169 (2010).
Crosta, X. et al. Last Abundant Appearance Datum of Hemidiscus karstenii driven by climate change. Mar. Micropaleontol. 157, 101861 (2020).
Schneider-Mor, A. et al. Nutrient regime at the siliceous belt of the Atlantic sector of the Southern Ocean during the past 660 ka. Paleoceanography 23, PA3217 (2008).
Turney, C. S. M. et al. Early Last Interglacial ocean warming drove substantial ice mass loss from Antarctica. Proc. Natl Acad. Sci. USA 117, 3996–4006 (2020).
Bamber, J. L., Riva, R. E. M., Vermeersen, B. L. A. & Lebrocq, A. M. Reassessment of the potential sea-level rise from a collapse of the West Antarctic Ice Sheet. Science 324, 901–903 (2009).
Colville, E. J. et al. Sr-Nd-Pb isotope evidence for ice-sheet presence on Southern Greenland during the Last Interglacial. Science 333, 620–623 (2011).
Ross, N. et al. Steep reverse bed slope at the grounding line of the Weddell Sea sector in West Antarctica. Nat. Geosci. 5, 393–396 (2012).
Golledge, N. R., Levy, R. H., McKay, R. M. & Naish, T. R. East Antarctic ice sheet most vulnerable to Weddell Sea warming. Geophys. Res. Lett. 44, 2343–2351 (2017).
Sun, S. et al. Antarctic ice sheet response to sudden and sustained ice-shelf collapse (ABUMIP). J. Glaciol. 66, 891–904 (2020).
Bayon, G. et al. An improved method for extracting marine sediment fractions and its application to Sr and Nd isotopic analysis. Chem. Geol. 187, 179–199 (2002).
Tanaka, T. et al. Jndi-1: A neodymium isotopic reference in consistency with LaJolla neodymium. Chem. Geol. 168, 279–281 (2000).
Weis, D. et al. High-precision isotopic characterization of USGS reference materials by TIMS and MC-ICP-MS. Geochem. Geophys. Geosyst. 7, Q08006 (2006).
McCave, I. N. & Hall, I. R. Size sorting in marine muds: Processes, pitfalls, and prospects for paleoflow-speed proxies. Geochem. Geophys. Geosyst. 7, Q10N05 (2006).
Itaki, T. Elutriation technique for extracting radiolarian skeletons from sandy sediments and its usefulness for faunal analysis. Radiolaria 24, 14–18 (2006).
Sakamoto, T. et al. Non-destructive X-ray fluorescence (XRF) core-imaging scanner. TATSCAN-F2. Sci. Drill. 2, 37–39 (2006).
Bourlès, D. L., Raisbeck, G. M. & Yiou, F. 10Be and 9Be in marine sediments and their potential for dating. Geochim. Cosmochim. Acta 53, 443–452 (1989).
Simon, Q. et al. Authigenic 10Be/9Be ratios and 10Be-fluxes (230Thxs-normalized) in central Baffin Bay sediments during the last glacial cycle: Paleoenvironmental implications. Quat. Sci. Rev. 140, 142–162 (2016).
Matsuzaki, H. et al. Current status and future direction of MALT, the University of Tokyo. Nucl. Instrum. Methods Phys. Res. B Beam Interact. Mater. 223, 92–99 (2004).
Matsuzaki, H., Ohkura, M. A., Ishige, Y., Nogami, Y. & Okamoto, H. Photoinduced switching to metallic states in the two-dimensional organic Mott insulator dimethylphenazine-tetrafluorotetracyanoquinodimethane with anisotropic molecular stacks. P Phys. Rev. B Condens. Matter 91, 1–10 (2015).
Nishiizumi, K. et al. Absolute calibration of 10Be AMS standards. Nucl. Instrum. Methods Phys. Res. B Beam Interact. Mater. 258, 403–413 (2007).
Chmeleff, J., von Blanckenburg, F., Kossert, K. & Jakob, D. Determination of the 10Be half-life by multicollector ICP-MS and liquid scintillation counting. Nucl. Instrum. Methods Phys. Res. B Beam Interact. Mater. 268, 192–199 (2010).
Korschinek, G. et al. A new value for the half-life of 10Be by Heavy-Ion Elastic Recoil Detection and liquid scintillation counting. Nucl. Instrum. Methods Phys. Res. B Beam Interact. Mater. 268, 187–191 (2010).
Yokoyama, Y. et al. Widespread collapse of the Ross Ice Shelf during the late Holocene. Proc. Natl Acad. Sci. 113, 2354–2359 (2016).
Willenbring, J. K. & von Blanckenburg, F. Meteoric cosmogenic Beryllium-10 adsorbed to river sediment and soil: Applications for Earth-surface dynamics. Earth Sci. Rev. 98, 105–122 (2010).
Holloway, M. D. et al. The spatial structure of the 128 ka Antarctic sea ice minimum. Geophys. Res. Lett. 44, 11–129 (2017).
Brathauer, U., Abelmann, A., Gersonde, R., Niebler, H. S. & Fütterer, D. K. Calibration of Cycladophora davisiana events versus oxygen isotope stratigraphy in the subantarctic Atlantic Ocean—A stratigraphic tool for carbonate-poor Quaternary sediments. Mar. Geol. 175, 167–181 (2001).
Wu, L. et al. Productivity-climate coupling recorded in Pleistocene sediments off Prydz Bay (East Antarctica). Palaeogeogr. Palaeoclimatol. Palaeoecol. 485, 260–270 (2017).
Howard, W. R. & Prell, W. L. Late Quaternary surface circulation of the Southern Indian Ocean and its relationship to orbital variations. Paleoceanography 7, 79–117 (1992).
Martinson, D. G. et al. Age dating and the orbital theory of the ice ages: development of a high-resolution 0 to 300,000-year Chronostratigraphy1. Quat. Res. 27, 1–29 (1987).
Hays, J. D., Lozano, J. A., Shackleton, N. & Irving, G. Reconstruction of the Atlantic and western Indian Ocean sectors of the 18,000 B.P. Antarctic Ocean. Geol. Soc. Am. Mem. 145, 337–372 (1976).
Hayes, C. T. et al. A stagnation event in the deep South Atlantic during the last interglacial period. Science 346, 1514–1517 (2014).
Uemura, R. et al. Ranges of moisture-source temperature estimated from Antarctic ice cores stable isotope records over glacial-interglacial cycles. Climate 8, 1109–1125 (2012).
Matsuoka, K. et al. Quantarctica, an integrated mapping environment for Antarctica, the Southern Ocean, and sub-Antarctic islands. Environ. Model. Softw. 140, 105015 (2021).
Acknowledgements
O.S. acknowledges support from the Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Numbers 17H01166, 17H06318, and 20H00626. Mu.I. is supported by Grant-in-Aid for JSPS Fellows Grant Number 21J13181 and Sasagawa Scientific Research Grant from the Japan Society. Y.S. is supported by the JSPS KAKENHI Grant Numbers 16H05739, 17H06321, 19H00728. Ta. I. is supported by the JSPS KAKENHI Grant Numbers 21H01201. D.J.W. is supported by a Natural Environment Research Council independent research fellowship (NE/T011440/1). Thanks also go to N. Pratt for her kind technical support with detrital neodymium isotope measurements.
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O.S. designed the project. Mu.I., K.H., T.v.d.F., D.J.W., and O.S. conducted Nd isotope measurements. Y.S., M.H., and H.M. analysed Be isotopes. Mu.I. and To.I. measured the grain size. Mu.I. and Ta.I. measured the Radioralia assemblage. Mi.I. conducted the XRF analysis. All authors (Mu.I., O.S., D.J.W., Y.S., K.H., T.v.d.F., Mi.I, Ta.I., To.I., M.Y., M.H., H.M., and S.S.) interpreted the data and wrote the manuscript.
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Iizuka, M., Seki, O., Wilson, D.J. et al. Multiple episodes of ice loss from the Wilkes Subglacial Basin during the Last Interglacial. Nat Commun 14, 2129 (2023). https://doi.org/10.1038/s41467-023-37325-y
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DOI: https://doi.org/10.1038/s41467-023-37325-y
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