Regarding Bilinear Interpolation in CDO
Added by Pankaj Narula over 2 years ago
I have netcdf file of the wind vector (u component) and rainfall netcdf file. Wind data is at gaussian grids whereas rainfall data at from regular grids. I want to interpolate wind data exactly at rainfall grids. I used
cdo remapbil,r360x180 uwnd.10m.gauss.1979.nc uwnd_1979_regular.nc, but grids are not matching with that of the rainfall file in nature (Wind data is global and rainfall data is of India, my point is lat-lon arrangement is different). I am just a beginner at CDO. Please help.
| rainfall_1979 (3.22 MB) rainfall_1979 | Rainfall Data | ||
| uwnd_1979_regular.nc (90.3 MB) uwnd_1979_regular.nc | Wind Vector |
Replies (2)
RE: Regarding Bilinear Interpolation in CDO - Added by Pankaj Narula over 2 years ago
I am not able to edit this post. I am also attaching the original file of u-wind data.
| uwnd.10m.gauss.1979.nc (16.1 MB) uwnd.10m.gauss.1979.nc | Original U-wind |
RE: Regarding Bilinear Interpolation in CDO - Added by Karin Meier-Fleischer over 2 years ago
Hi Pankaj,
it is not the same as the rainfall_1979 grid because you remapped it to a 1x1 deg global grid. But the rainfall_1979 has a regional grid.
cdo sinfon rainfall_1979
File format : NetCDF
-1 : Institut Source T Steptype Levels Num Points Num Dtype : Parameter name
1 : unknown unknown v instant 1 1 1155 1 F64 : RAINFALL
Grid coordinates :
1 : lonlat : points=1155 (35x33)
LONGITUDE : 66.5 to 100.5 by 1 degrees_east
LATITUDE : 6.5 to 38.5 by 1 degrees_north
Vertical coordinates :
1 : surface : levels=1
Time coordinate :
TIME : 365 steps
RefTime = 1900-12-31 00:00:00 Units = days Calendar = standard
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
1979-01-01 00:00:00 1979-01-02 00:00:00 1979-01-03 00:00:00 1979-01-04 00:00:00
1979-01-05 00:00:00 1979-01-06 00:00:00 1979-01-07 00:00:00 1979-01-08 00:00:00
...
To remap the data to the rainfall_1979 grid you can use the file as grid description itself.
cdo remapbil,rainfall_1979 uwnd.10m.gauss.1979.nc uwnd_1979_regular_same_grid_as_rainfall_1979.nc
And when you now take a look at the grid you can see it is the same as for rainfall_1979.
cdo sinfon uwnd_1979_regular_same_grid_as_rainfall_1979.nc
File format : NetCDF4 classic
-1 : Institut Source T Steptype Levels Num Points Num Dtype : Parameter name
1 : NCEP NCEP/DOE v instant 1 1 1155 1 F32 : uwnd
Grid coordinates :
1 : lonlat : points=1155 (35x33)
LONGITUDE : 66.5 to 100.5 by 1 degrees_east
LATITUDE : 6.5 to 38.5 by 1 degrees_north
Vertical coordinates :
1 : generic : levels=1
level : 10 m
Time coordinate :
time : 365 steps
RefTime = 1800-01-01 00:00:00 Units = hours Calendar = standard Bounds = true
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
1979-01-01 00:00:00 1979-01-02 00:00:00 1979-01-03 00:00:00 1979-01-04 00:00:00
1979-01-05 00:00:00 1979-01-06 00:00:00 1979-01-07 00:00:00 1979-01-08 00:00:00
1979-01-09 00:00:00 1979-01-10 00:00:00 1979-01-11 00:00:00 1979-01-12 00:00:00
...