rewriting nc file using land mask
Added by kartk ram about 9 years ago
Hello folks,
I am looking for some priliminary help. I have global netcdf data file. I want to make a new .nc file from it but only with ocean data points. I understand from general reading taht i have to mask the land but dont have a clue about it. Seekiing your valuable help.
thanks in advance
Replies (1)
RE: rewriting nc file using land mask - Added by Jaison-Thomas Ambadan about 9 years ago
Hi,
you can use the topo operator along with comparison operators for your purpose: https://code.zmaw.de/boards/53/topics/1605
For more info regarding the comparison operators: https://code.zmaw.de/projects/cdo/embedded/1.6.4/cdo.html#x1-1470002.5
here is an example,
cdo -f nc -gtc,0 -topo land_sea_mask.nc
will give half degree regular grid mask file (1s over the land and 0s over the ocean). To change the resolution of the mask, use remap operators on topo and then use the comparison operator
Another option is to use the GMT tool grdlandmask : http://gmt.soest.hawaii.edu/doc/latest/grdlandmask.html
Cheers