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

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

md5sum output	Data file
3796bd615de2811f593483d648b94562	GLAC-1D.sftlf.21_DIRTY-CASPIAN.nc
e8be8847a4dabd0a446682d51f6d77c3	TOPicemsk.GLACD26kN9894GE90227A6005GGrBgic.nc