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GEUS-Glaciology-and-Climate / ice_discharge

Greenland Ice Sheet solid ice discharge from 1986 through last month
https://doi.org/10.5194/essd-12-1367-2020
GNU Lesser General Public License v3.0
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Upgrade to BedMachine v4 #26

Closed mankoff closed 3 years ago

mankoff commented 3 years ago

Per email discussion with @mmorligh, BedMachine v4 is now in EPSG:3411 projection.

I reproject to 3413 using the following code (1x, not contained in this repository, hence posted here):

vars=$(cdo showname BedMachineGreenland-2021-04-20.nc)
mkdir -p BMv4_3411 BMv4_3413
parallel --bar "gdal_translate -co COMPRESS=DEFLATE NetCDF:BedMachineGreenland-2021-04-20.nc:{1} ./BMv4_3411/{1}.tif" ::: ${vars}
parallel --bar "gdalwarp -co COMPRESS=DEFLATE -t_srs EPSG:3413 ./BMv4_3411/{1}.tif ./BMv4_3413/{1}.tif" ::: ${vars}

And the new code will load the GeoTIFFs from ${DATADIR}/Morlighem_2017/BMv4_3413/.

mankoff commented 3 years ago

The effect of BMv4 upgrade & removing Millan (2018) patching in SE is a ~10 Gt/year or ~2 % decrease in total discharge (old 500 Gt/yr is now ~490 Gt/yr), but a ~5 Gt/year or ~10 % decrease in uncertainty (from ~50 Gt/year to ~45 Gt/year).