Abstract:
Global monthly outputs of orography, surface air temperature and water stable isotopes (d18O) were run by the isotope-enabled atmosphere/ocean coupled model HadCM3 for the last interglacial (128 ka). An ensemble of ten idealised Antarctic Ice Sheet (AIS) simulations were processed, included a pre-industrial and a last interglacial control simulations. The eight other simulations used changed topography of the AIS relative to Dome C to ensure the preservation of the atmospheric pathways. The simulations were run 100 years and the last 50 years were used for the analyses.
This work was funding through the European Research Council under the Horizon 2020 research and innovation programme (grant agreement No 742224, WACSWAIN) and NERC grant NE/P009271/1.
Keywords:
Antarctica, climate modelling, effect of the elevation, last interglacial, water stable isotopes
Goursaud, S., Holloway, M., Sime, L., Wolff, E., Valdes, P., Steig, E., & Pauling, A. (2020). Global monthly outputs of orography, surface air temperature and water stable isotopes for the last interglacial for idealised Antarctic Ice Sheet simulations run by the isotope-enabled HadCM3 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/09330d14-7f2d-4c12-ad00-08a9cd1fb214
| Access Constraints: | No restrictions apply. |
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| Use Constraints: | This data is supplied under Open Government Licence v3.0 http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/. |
| Creation Date: | 2020-11-06 |
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| Dataset Progress: | Complete |
| Dataset Language: | English |
| ISO Topic Categories: |
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| Parameters: |
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| Personnel: | |
| Name | UK Polar Data Centre |
| Role(s) | Metadata Author |
| Organisation | British Antarctic Survey |
| Name | Sentia Goursaud |
| Role(s) | Technical Contact, Investigator |
| Organisation | University of Cambridge |
| Name | Max Holloway |
| Role(s) | Investigator |
| Organisation | British Antarctic Survey |
| Name | Louise Sime |
| Role(s) | Investigator |
| Organisation | British Antarctic Survey |
| Name | Eric Wolff |
| Role(s) | Investigator |
| Organisation | University of Cambridge |
| Name | Paul Valdes |
| Role(s) | Investigator |
| Organisation | University of Bristol |
| Name | Eric Steig |
| Role(s) | Investigator |
| Organisation | University of Washington |
| Name | Andrew Pauling |
| Role(s) | Investigator |
| Organisation | University of Washington |
| Parent Dataset: | N/A |
| Reference: | Holloway, M. D., Sime, L. C., Singarayer, J. S., Tindall, J. C., Bunch, P., & Valdes, P. J. (2016, aug). Antarctic last interglacial isotope peak in response to sea ice retreat not ice-sheet collapse. Nature Communications, 7 , 12293. doi: 10.1038/ncomms12293 Holloway, M. D., Sime, L. C., Singarayer, J. S., Tindall, J. C., & Valdes, P. J. (2018). Simulating the 128 ka Antarctic climate response to Northern Hemisphere ice sheet melting using the isotope-enabled HadCM3. Geophysical Research Letters. doi: 10.1029/2018GL079647 Masson-Delmotte, V., Buiron, D., Ekaykin, a., Frezzotti, M., Gallée, H., Jouzel, J., Vimeux, F. (2011, apr). A comparison of the present and last interglacial periods in six Antarctic ice cores. Climate of the Past, 7 (2), 397-423. doi: 10.5194/cp-7-397-2011 Parrenin, F., Dreyfus, G., Durand, G., Fujita, S., Gagliardini, O., Gillet, F., Kawamura, K. (2007). 1-D-ice flow modelling at EPICA Dome C and Dome Fuji , East Antarctica. Climate of the Past, 3 , 243-259. doi: 10.5194/cp-3-243-2007 Sime, L. C., Wolff, E. W., Oliver, K. I. C., & Tindall, J. C. (2009, nov). Evidence for warmer interglacials in East Antarctic ice cores. Nature, 462 , 342-345. doi: 10.1038/nature08564 Tindall, J. C., Valdes, P. J., & Sime, L. C. (2009, feb). Stable water isotopes in HadCM3: Isotopic signature of El Niño - Southern Oscillation and the tropical amount effect. Journal of Geophysical Research, 114 , 12pp. doi: 10.1029/2008JD010825 |
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| Quality: | No quality control procedures out of the described methodology were processed. | |
| Lineage: | The isotopic response to idealised changes in AIS elevation are simulated using the isotope-enabled coupled ocean--atmosphere--sea-ice General Circulation Model, HadCM3 (Tindall et al., 2009). Two control simulations were used: a pre-industrial (PI) simulation, and a 128 ka simulation centred on the last interglacial (LIG) Antarctic isotope maximum including a modern day AIS configuration (Holloway et al., 2016). Then a suite of eight idealised AIS elevation change simulations were performed using orbital and greenhouse-gas forcing at 128 ka. Each experiment scaled the AIS and relates the change to elevation at the EPICA Dome C (EDC) ice core site following: beta = ZEDC / (ZEDC + DeltaZ) where ZEDC is the EDC ice core site elevation in the modern day AIS configuration, DeltaZ is the prescribed elevation change which extends to +/- 1000 m, and beta is the scaling coefficient. Elevations across the Antarctic continent are then increased or decreased proportional to beta; ZA' = ZA / beta where ZA is the two-dimensional array of modern AIS elevations and ZA' is a new array of altered AIS elevations. This approach maintains the modern shape of the AIS, thus reducing the influence of changing ice sheet configuration on circulation and climate and isolating the effect of elevation changes alone. We perform experiments with DeltaZ equal to (+/-) 100, 200, 500 and 1000 m. Each of the above elevation change scenarios is integrated for a total of 500-years to ensure that surface and mid-depth climate fields are sufficiently spun-up with the imposed elevation changes. The last 50 years of each simulation are analysed. LIG Antarctic isotope maximum of between +2-4 per mille above PI in d18O are recorded in East Antarctic ice cores. We evaluate our elevation scenarios against LIG d18O maxima from five published ice core records from East Antarctica (Masson Delmotte et al., 2011): Vostok, Dome Fuji, EPICA Dome C, EPICA Dronning Maud Land and Talos Dome Ice Core. The records are processed following the approach outlined in Holloway et al. (2017): The ice core isotope records are synchronised to the EDC3 age scale (Parrenin et al., 2007) and interpolated onto a common 100 year time grid. Any residual temporal misalignment between the ice cores is minimised by applying a 1500 yr low-pass filter to each record before taking the LIG peak (Sime et al., 2009). Fractional isotopic content is expressed for oxygen-18 as: d18O = 1000 x (H218O / H216O) / RVSMOW-1 in per mille, where RVSMOW is the ratio of H218O to H216O for Vienna standard mean ocean water. |
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| Paleo Temporal Coverage: | |
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| Paleo Start Date | 128 ka |
| Paleo End Date | 128 ka |
| Chronostratigraphic Unit | N/A |
| Spatial Coverage: | |
| Latitude | |
| Southernmost | -90 |
| Northernmost | 90 |
| Longitude | |
| Westernmost | -180 |
| Easternmost | 180 |
| Altitude | |
| Min Altitude | N/A |
| Max Altitude | N/A |
| Depth | |
| Min Depth | N/A |
| Max Depth | N/A |
| Data Resolution: | |
| Latitude Resolution | 2.5 degrees |
| Longitude Resolution | 3.75 degrees |
| Horizontal Resolution Range | N/A |
| Vertical Resolution | N/A |
| Vertical Resolution Range | N/A |
| Temporal Resolution | N/A |
| Temporal Resolution Range | N/A |
| Location: | |
| Location | Global |
| Detailed Location | N/A |
| Data Collection: | Model code developed to analyse the outputs can be found on Github: https://github.com/aitens/Antarctic-Ice-Sheet-elevation-impacts-on-water-isotope-records-during-the-Last-Interglacial. To analyse the outputs using the model code, one needs python 2.7 (or 3), with modules likes matplotlib, numpy, iris. The model was run using 128k orbital parameters for 100 years. Data consist of surface outputs (1 level) with global coverage (longitude from 0 to 360 degrees and latitude from -90 to 90 degrees). When analysing the outputs, a focus was made on location of ice cores covering the last interglacial: Vostok (E106.8, S78.5), Dome F (E39.7, S77.3), EDC (E123.4, S75.1), EDML (E0.07, S75.0), Taylor Dome (E158.7, S77.8), TALDICE (E159.2, S72.8), WAIS Divide (E247.9, S79.5), Hercules Dome (E255, S86), Skytrain (E280.3, S78). |
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| Distribution: | |
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| Distribution Media | Online Internet (HTTP) |
| Distribution Size | 109 MB |
| Distribution Format | netCDF |
| Fees | N/A |
| Data Storage: | There are 10 simulations, one per netCDF file. |