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    This data publication contains biostratigraphic age events for the CIROS-1 drill core, updated age ranges for a suite of samples from the McMurdo erratics sample collection, age-depth tie points for CIROS-1, CRP-2/2A, DSDP 270, DSDP 274, ANDRILL 2A and ANDRILL 1B, and glycerol dialkyl glycerol tetraethers (GDGTs) abundances and indices for samples from the McMurdo erratics, CIROS-1, CRP-2/2A, DSDP 270, DSDP 274, ANDRILL 2A, and ANDRILL 1B. All sample sites are in the Ross Sea region of Antarctica. The McMurdo erratics are glacial erratics collected in the McMurdo Sound region between 1991 and 1996 (Harwood and Levy, 2000). The CIROS-1 drill core was collected from McMurdo sound in 1986 with samples spanning the upper Eocene to lower Miocene. CRP-2/2A drill core was collected in 1999 from offshore Victoria Land with samples for this study from the upper Oligocene-lower Miocene. DSDP Site 270 was recovered from the Eastern Basin of the central Ross Sea in 1973, with samples spanning the upper Oligocene-lower Miocene. DSDP Site 274 was drilled on the lower continental rise in the northwestern Ross Sea in 1973, and samples for this study have been taken from the middle Miocene sections of the drill core. The ANDRILL-2A core was recovered in 2007 from Southern McMurdo Sound, samples span the lower Miocene to middle Miocene and data was originally published in Levy et al. (2016). The ANDRILL-IB core was drilled from the McMurdo Ice Shelf in 2006, samples are compiled from the Plio-Pleistocene section of the core and were originally published in McKay et al. (2012). Biostratigraphic age events are described for CIROS-1, expanding on and updating previously published age models and biostratigraphic ranges. Ages are also revised for the McMurdo erratics by updating the ages of the biostratigraphic markers described by (Harwood and Levy (2000) to more recently published age ranges. Age models for the sample sites are developed using published age datums and the Bayesian age-depth modelling functionality in the R package Bchron (Haslett and Parnell, 2008) to ensure a consistent approach for assigning ages to core depths between datums. GDGT abundances and indices for Ross Sea sites are presented to reconstruct ocean temperatures over the Cenozoic era. Detailed methodology for the processing and analysis of samples for GDGTs is described in the methods section of supplement paper.

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    In collaboration between Korea Polar Research Institute and NIWA, an oceanographic mooring was deployed to the south of the Drygalski Ice Tongue (lat:-75.488417, lon:163.174350) on 12 February 2017 as a part of the ANA07C research cruise, and it was recovered on 7 March 2018. To monitor physical properties (Temperature, Salinity, Current) of ocean water in the south of the Drygalski Ice Tongue. GET DATA: https://kpdc.kopri.re.kr/search/9245184f-b187-4c1e-ad6f-32ed1f9493c8

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    In collaboration between Korea Polar Research Institute and NIWA, an oceanographic mooring was deployed to the North of the Drygalski Ice Tongue (lat:-75.360767, lon:164.746467) on 9 February 2017 as a part of the ANA07C research cruise, and it was recovered on 5 March 2018. To monitor physical properties (Temperature, Salinity, Current) of ocean water in the north of the Drygalski Ice Tongue. GET DATA: https://kpdc.kopri.re.kr/search/c266365d-4846-4242-952b-75102a53110b

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    In collaboration between Korea Polar Research Institute LDEO and NIWA, an oceanographic mooring was deployed close to the bottom depth in the Drygalski Basin (lat:-75.010487, lon:165.555680) on 6 March 2018 as a part of the ANA08C research cruise, and it was recovered on 5 January 2019. To monitor physical properties (Temperature, Salinity, Current) of deep water in the Drygalski Basin. GET DATA: https://kpdc.kopri.re.kr/search/992862c1-84d0-46aa-97dd-e2dcfb12357e

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    The data are approximately 800 km of airborne electromagnetic survey of coastal sea ice and sub-ice platelet layer (SIPL) thickness distributions in the western Ross Sea, Antarctica, from McMurdo Sound to Cape Adare. Data were collected between 8 and 13 November 2017, within 30 days of the maximum fast ice extent in this region. Approximately 700 km of the transect was over landfast sea ice that had been mechanically attached to the coast for at least 15 days. Most of the ice was first-year sea ice. Unsmoothed in-phase and quadrature components are presented at all locations. Data have been smoothed with an 100 point median filter, and in-phase and quadrature smoothed data are also presented at all locations. Beneath level ice it is possible to identify the thickness of an SIPL and a filter is described (Langhorne et al) to identify level ice. Level ice in-phase, quadrature and SIPL thickness, derived from these, are presented at locations of level ice. For rough ice, the in-phase component is considered the best measure of sea ice thickness. For level ice where there is the possibility of an SIPL, then the quadrature component is considered the best measure of ice thickness, along with SIPL thickness. All data are in meters.

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    Here, we present new, transient, GCM-forced ice-sheet simulations validated against proxy reconstructions. This is the first time such an evaluation has been attempted. Our empirically constrained simulations indicate that the AIS contributed 4 m to global mean sea level by 126 ka BP, with ice lost primarily from the Amundsen, but not Ross or Weddell Sea, sectors. We resolve the conflict between previous work and show that the AIS thinned in the Wilkes Subglacial Basin but did not retreat. We also find that the West AIS may be predisposed to future collapse even in the absence of further environmental change, consistent with previous studies. There are two files, for Termination 1 ('T1') and Termination 2 ('T2'). They contain spatial fields for ice thickness, ice surface elevation, bedrock elevation, surface and basal velocity, and mask. The T1 outputs are every 500 years, whereas the T2 outputs are every 100 years. The spatial resolution of both is 20 km. Sea-level-equivalent mass loss can be calculated from these outputs, but is also provided here in a text file for convenience. RELATED PUBLICATION: Golledge, N.R., Clark, P.U., He, F., et al. (2021). Retreat of the Antarctic Ice Sheet During the Last Interglaciation and Implications for Future Change. Geophysical Research Letters, 48(17). https://doi.org/10.1029/2021GL094513 GET DATA: https://doi.org/10.17605/OSF.IO/GZB3H

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    The data are approximately 800 km of airborne electromagnetic survey of coastal sea ice and sub-ice platelet layer (SIPL) thickness distributions in the western Ross Sea, Antarctica, from McMurdo Sound to Cape Adare. Data were collected between 8 and 13 November 2017, within 30 days of the maximum fast ice extent in this region. Approximately 700 km of the transect was over landfast sea ice that had been mechanically attached to the coast for at least 15 days. Most of the ice was first-year sea ice. Unsmoothed in-phase and quadrature components are presented at all locations. Data have been smoothed with an 100 point median filter, and in-phase and quadrature smoothed data are also presented at all locations. Beneath level ice it is possible to identify the thickness of an SIPL and a filter is described (Langhorne et al) to identify level ice. Level ice in-phase, quadrature and SIPL thickness, derived from these, are presented at locations of level ice. For rough ice, the in-phase component is considered the best measure of sea ice thickness. For level ice where there is the possibility of an SIPL, then the quadrature component is considered the best measure of ice thickness, along with SIPL thickness. All data are in meters.

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    The data are approximately 800 km of airborne electromagnetic survey of coastal sea ice and sub-ice platelet layer (SIPL) thickness distributions in the western Ross Sea, Antarctica, from McMurdo Sound to Cape Adare. Data were collected between 8 and 13 November 2017, within 30 days of the maximum fast ice extent in this region. Approximately 700 km of the transect was over landfast sea ice that had been mechanically attached to the coast for at least 15 days. Most of the ice was first-year sea ice. Unsmoothed in-phase and quadrature components are presented at all locations. Data have been smoothed with an 100 point median filter, and in-phase and quadrature smoothed data are also presented at all locations. Beneath level ice it is possible to identify the thickness of an SIPL and a filter is described (Langhorne et al) to identify level ice. Level ice in-phase, quadrature and SIPL thickness, derived from these, are presented at locations of level ice. For rough ice, the in-phase component is considered the best measure of sea ice thickness. For level ice where there is the possibility of an SIPL, then the quadrature component is considered the best measure of ice thickness, along with SIPL thickness. All data are in meters.

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    In collaboration between the Korea Polar Research Institute and NIWA, an oceanographic mooring was deployed close to the bottom depth near the Drygalski Ice Tongue (lat:-75.275700, lon:164.067300) on 9 March 2018 as a part of the ANA08C research cruise, and it was recovered on 3 January 2019 To monitor physical properties(Temperature, Salinity, Current) of deep water near the Drygalski Ice Tongue. To monitor physical properties (Temperature, Salinity, Current) of deep water near the Drygalski Ice Tongue. GET DATA: https://kpdc.kopri.re.kr/search/9826749c-376a-4751-8812-702cec76c4c0

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    In collaboration between Korea Polar Research Institute and NIWA, an oceanographic mooring was deployed close to the bottom depth near the Drygalski Ice Tongue (lat:-75.275700, lon:164.067300) on 9 March 2018 as a part of the ANA08C research cruise, and it was recovered on 3 January 2019. To monitor physical properties (Temperature, Salinity, Current) of deep water near the Drygalski Ice Tongue. GET DATA: https://kpdc.kopri.re.kr/search/9826749c-376a-4751-8812-702cec76c4c0