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Latitudes and Longitudes output after regridding with remapbil

Added by Julie Jones almost 9 years ago

Hello,

I'm using the command remapbil, regridding ERA interim 10m u-wind data with an original resolution of 2.5 degrees by 2.5 degrees.

cdo remapbil,r45x23 inputfile.nc outputfile.nc

The output latitudes are:

-90.0000  -81.8182  -73.6364  -65.4545  -57.2727  -49.0909  -40.9091  -32.7273  -24.5455  -16.3636   -8.1818         0  8.1818   16.3636   24.5455   32.7273   40.9091   49.0909   57.2727   65.4545   73.6364   81.8182   90.0000

The output longitudes are:

0 8 16 24 32 40 48 56 64 72 80 88 96 104 112 120 128 136 144 152 160 168 176 184 192 200 208 216 224 232 240 248 256 264 272 280 288 296 304 312 320 328 336 344 352

So if one starts at -90, then I think that the latitude and longitude would be for the bottom left corner of a gridbox, but that would mean that the final gridbox with latitude 90 degrees would have data north of the north pole, which is obviously not possible.

Also, when I regrid to 45 by 24
cdo remapbil,r45x24 inputfile.nc outputfile.nc

the latitudes come out as

-86.2500 -78.7500 -71.2500 -63.7500 -56.2500 -48.7500 -41.2500 -33.7500 -26.2500 -18.7500 -11.2500 -3.7500
3.7500 11.2500 18.7500 26.2500 33.7500 41.2500 48.7500 56.2500 63.7500 71.2500 78.7500 86.2500

With the longitudes the same as above, which seems to suggest that the latitude and longitude are for the mid-left of the gridbox.

Any help would be much appreciated on which lat and lon are given in the output by CDO.

Thanks and best wishes,

Julie


Replies (1)

RE: Latitudes and Longitudes output after regridding with remapbil - Added by Brendan DeTracey almost 9 years ago

Lat and lon are for the grid cell centre. As you have seen, it is a bad idea to use an odd number for NY.

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