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PMIP4 GLAC-1D ice-sheet data
Grid
- nb_lat, nb_lon = 360, 360
- latitude_values = [ -89.75, -89.25, -88.75, … 88.75, 89.25, 89.75 ]
- longitude_values = [ 0.5, 1.5, 2.5, … 357.5, 358.5, 359.5 ]
- time axis: see the Time steps section below
Time steps and data files
- 261 time steps in one file, from 0k to 26k : data every 100 years, from 0k to 26k BP
- time_values = [ -26. , -25.9, -25.8, … -0.2, -0.1, 0. ]
- all the variables and all the time steps are in the same file:
TOPicemsk.GLACD26kN9894GE90227A6005GGrBgic.nc
Variables
- HDC: GLAC contemp. elevation(masl), meters
- on continents (including ice sheets) and ice shelves: surface altitude (including ice sheets/shelves)
- on ice-free ocean: bathymetry
- HDCB: GLAC contemp. elevation(masl), bathymetry for floating ice, meters
- on continents (including ice sheets) and ice shelves: surface altitude (including ice sheets)
- on ice-shelves: altitude of the bottom of the floating ice
- on ice-free ocean: bathymetry
- ICEM: GLAC ice mask, fraction
- ice fraction values between 0.0 (no ice) and 1.0 (100% ice)
Notes:
- The land-sea mask can be computed with:
- HDCB > 0 : ls_mask = 1 (land)
- HDCB ≤ 0 : ls_mask = 0 (no land)
- Computing the
HDC-HDCB
difference yields:- ice-shelves thickness where there are ice shelves
- 0.0 everywhere else
References
Please cite all the following papers:
- L. Tarasov and W. Richard Peltier Greenland glacial history and local geodynamic consequences, Geophysical Journal International, 150, 198-229, doi:10.1046/j.1365-246X.2002.01702.x
- Lev Tarasov, Arthur S. Dyke, Radford M. Neal and W.R. Peltier, A data-calibrated distribution of deglacial chronologies for the North American ice complex from glaciological modeling, Earth and Planetary Science Letters, Volumes 315–316, 15 January 2012, Pages 30–40, doi:10.1016/j.epsl.2011.09.010
- Robert D. Briggs , David Pollard , Lev Tarasov, A data-constrained large ensemble analysis of Antarctic evolution since the Eemian, Quaternary Science Reviews, Volume 103, 1 November 2014, Pages 91–115, doi:10.1016/j.quascirev.2014.09.003
- 4th paper to be added here (Eurasian component)
Download
You will find below a table with all the available data files, and their md5sum checksum (if you want to check that you download was OK, you can just type md5sum file.nc
and compare the result to what is displayed in the table).
If you want to download a file, click on the ice_sheet download link and then on the file you need. The files are currently protected by a password. Get in touch with Jean-Yves Peterschmitt if you need to access them.
Groups running the lgm experiment have to use the GLAC-1D.sftlf.21_DIRTY-CASPIAN.nc
land-sea mask file, where the Caspian sea has been set to the modern Caspian sea in the land-sea mask variable.
The files for the entire deglaciation have not been modified accordingly yet.
md5sum output | Data file |
---|---|
3796bd615de2811f593483d648b94562 | GLAC-1D.sftlf.21_CASPIAN.nc |
e8be8847a4dabd0a446682d51f6d77c3 | TOPicemsk.GLACD26kN9894GE90227A6005GGrBgic.nc |