Extract values for station coordinates
Added by Jonas Müller over 4 years ago
Hello,
I am currently working with model data of the German weather service, which are available in .grb format.
I have already converted these into .nc files with the CDO package in Ubuntu.
Now I wanted to know if there is a possibility to extract the values for certain station coordinates from this model data with the CDO package?
Thanks in advance
Replies (3)
RE: Extract values for station coordinates - Added by Ralf Mueller over 4 years ago
hi Jonas!
Since the grid is not part of the data, you have to download it separately from https://opendata.dwd.de/weather/lib/cdo/.
check which grid is needed with
cdo sinfolike this:
% cdo sinfov icon_global_icosahedral_single-level_2019100612_018_U_10M.grib2
File format : GRIB2
-1 : Institut Source T Steptype Levels Num Points Num Dtype : Parameter name
1 : DWD unknown v instant 1 1 2949120 1 P16 : 10u
Grid coordinates :
1 : unstructured : points=2949120
grid : number=26 position=1
uuid : a27b8de6-18c4-11e4-820a-b5b098c6a5c0
Vertical coordinates :
1 : height : levels=1
height : 10 m
Time coordinate : 1 step
RefTime = 2019-10-06 12:00:00 Units = minutes Calendar = proleptic_gregorian
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
2019-10-07 06:00:00
cdo sinfon: Processed 1 variable over 1 timestep [0.09s 66MB].
CDO prints a grid number (26) and a UUID. Download the correct one and attach it to the data within your CDO call:
% cdo sinfov -sellonlatbox,0,10,-10,10 -setgrid,icon_grid_0026_R03B07_G.nc icon_global_icosahedral_single-level_2019100612_018_U_10M.grib2
cdo(1) sellonlatbox: Process started
cdo(2) setgrid: Process started
File format : GRIB2
-1 : Institut Source T Steptype Levels Num Points Num Dtype : Parameter name
1 : DWD unknown v instant 1 1 13899 1 P16 : 10u
Grid coordinates :
1 : unstructured : points=13899 nvertex=3
clon : 8.511765e-17 to 0.1745291 radian
clat : -0.1745276 to 0.1745085 radian
available : cellbounds
Vertical coordinates :
1 : height : levels=1
height : 10 m
Time coordinate : 1 step
RefTime = 2019-10-06 12:00:00 Units = minutes Calendar = proleptic_gregorian
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
2019-10-07 06:00:00
cdo(2) setgrid: Processed 1 variable over 1 timestep.
cdo(1) sellonlatbox: Processed 2949120 values from 1 variable.
cdo sinfon: Processed 1 variable [0.74s 950MB].
for the selection of a special location I recommend using remapnn or what ever interpolation you like:
cdo infov -remapnn,lon=-22.2_lat=54.9 -setgrid,icon_grid_0026_R03B07_G.nc icon_global_icosahedral_single-level_2019100612_018_U_10M.grib2
hth
ralf
RE: Extract values for station coordinates - Added by Jonas Müller over 4 years ago
Hi Ralf!
I cant upload my data cause its to big but i can give u the download link (https://opendata.dwd.de/climate_environment/REA/COSMO_REA6/hourly/2D/CLCT/) - CLCT.2D.200901.grb
When I get the command "cdo sinfo CLCT.2D.200901.grb" I get the following output:
root@DESKTOP-PPMRK6S:/home/jonas/CDO/CLCT# cdo sinfo CLCT.2D.200901.grb
File format : GRIB
-1 : Institut Source T Steptype Levels Num Points Num Dtype : Parameter ID
1 : DWD unknown v instant 1 1 698752 1 P16 : 71.2
Grid coordinates :
1 : projection : points=698752 (848x824)
mapping : rotated_latitude_longitude
rlon : -28.403 to 18.182 by 0.055 degrees
rlat : -23.403 to 21.863 by 0.05500122 degrees
Vertical coordinates :
1 : surface : levels=1
Time coordinate : unlimited steps
RefTime = 2009-01-01 01:00:00 Units = hours Calendar = proleptic_gregorian
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
2009-01-01 01:00:00 2009-01-01 02:00:00 2009-01-01 03:00:00 2009-01-01 04:00:00
2009-01-01 05:00:00 2009-01-01 06:00:00 2009-01-01 07:00:00 2009-01-01 08:00:00
2009-01-01 09:00:00 2009-01-01 10:00:00 2009-01-01 11:00:00 2009-01-01 12:00:00
2009-01-01 13:00:00 2009-01-01 14:00:00 2009-01-01 15:00:00 2009-01-01 16:00:00
2009-01-01 17:00:00 2009-01-01 18:00:00 2009-01-01 19:00:00 2009-01-01 20:00:00
2009-01-01 21:00:00 2009-01-01 22:00:00 2009-01-01 23:00:00 2009-01-02 00:00:00
2009-01-02 01:00:00 2009-01-02 02:00:00 2009-01-02 03:00:00 2009-01-02 04:00:00
2009-01-02 05:00:00 2009-01-02 06:00:00 2009-01-02 07:00:00 2009-01-02 08:00:00
2009-01-02 09:00:00 2009-01-02 10:00:00 2009-01-02 11:00:00 2009-01-02 12:00:00
2009-01-02 13:00:00 2009-01-02 14:00:00 2009-01-02 15:00:00 2009-01-02 16:00:00
2009-01-02 17:00:00 2009-01-02 18:00:00 2009-01-02 19:00:00 2009-01-02 20:00:00
2009-01-02 21:00:00 2009-01-02 22:00:00 2009-01-02 23:00:00 2009-01-03 00:00:00
2009-01-03 01:00:00 2009-01-03 02:00:00 2009-01-03 03:00:00 2009-01-03 04:00:00
2009-01-03 05:00:00 2009-01-03 06:00:00 2009-01-03 07:00:00 2009-01-03 08:00:00
2009-01-03 09:00:00 2009-01-03 10:00:00 2009-01-03 11:00:00 2009-01-03 12:00:00
................................................................................
.......................................................
2009-01-29 13:00:00 2009-01-29 14:00:00 2009-01-29 15:00:00 2009-01-29 16:00:00
2009-01-29 17:00:00 2009-01-29 18:00:00 2009-01-29 19:00:00 2009-01-29 20:00:00
2009-01-29 21:00:00 2009-01-29 22:00:00 2009-01-29 23:00:00 2009-01-30 00:00:00
2009-01-30 01:00:00 2009-01-30 02:00:00 2009-01-30 03:00:00 2009-01-30 04:00:00
2009-01-30 05:00:00 2009-01-30 06:00:00 2009-01-30 07:00:00 2009-01-30 08:00:00
2009-01-30 09:00:00 2009-01-30 10:00:00 2009-01-30 11:00:00 2009-01-30 12:00:00
2009-01-30 13:00:00 2009-01-30 14:00:00 2009-01-30 15:00:00 2009-01-30 16:00:00
2009-01-30 17:00:00 2009-01-30 18:00:00 2009-01-30 19:00:00 2009-01-30 20:00:00
2009-01-30 21:00:00 2009-01-30 22:00:00 2009-01-30 23:00:00 2009-01-31 00:00:00
2009-01-31 01:00:00 2009-01-31 02:00:00 2009-01-31 03:00:00 2009-01-31 04:00:00
2009-01-31 05:00:00 2009-01-31 06:00:00 2009-01-31 07:00:00 2009-01-31 08:00:00
2009-01-31 09:00:00 2009-01-31 10:00:00 2009-01-31 11:00:00 2009-01-31 12:00:00
2009-01-31 13:00:00 2009-01-31 14:00:00 2009-01-31 15:00:00 2009-01-31 16:00:00
2009-01-31 17:00:00 2009-01-31 18:00:00 2009-01-31 19:00:00 2009-01-31 20:00:00
2009-01-31 21:00:00 2009-01-31 22:00:00 2009-01-31 23:00:00 2009-02-01 00:00:00
cdo sinfo: Processed 1 variable over 744 timesteps [0.78s 38MB]
If I'm not mistaken, there's already a grid here.
So now i want to select the data for following coordinates:
latitude= 53.0316; longitude= 13.9907
So what do i have to do now?
Sorry, but i am a complete beginner at ubuntu and cdo.
Thanks in advance.
Jonas
RE: Extract values for station coordinates - Added by Ralf Mueller over 4 years ago
hi!
latitude range is from -23.403 to 21.862, so there will be no point with lat=53.0316 I think.
If it was there your would use
cdo remapnn,lon=13.9907_lat=53.0316 <ifile> <ofile>and get the values at the nearest cell of the grid.
hth
ralf