>Im working with reanalysis data that has 277 grid boxes for lat and 349
>boxes for lon. I'd like to narrow the area to specific lat and lon (one
>grid box) and then output certain variables in that region to netcdf.
>Is there a way to do this in the script you provide to convert grib to
>netcdf?
The short answer is "yes, of course!"
[1] I assume you are working with the NARR
[North American Regional Reanalysis] dataset
[2] You say "one grid box"
[a] Do u mean one point?
[b] Do u mean 4 points that define an area?
What point(s) ?
[3] What do u mean by: "the script you provide to
convert grib to netcdf"
What "script you provide" are you referring to?
The a034 release [Jan 2006] of NCL will have a command
line tool [ncl_grib2nc] that will convert GRIB to netCDF. However,
it will not provide the level of granularity described above.
--- If you know the subscript location(s) of the point(s) you want, say, i and j, then [***untested***] load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl" begin i = j = fili = "foo.grb" fout = "foo.nc" f = addfile (fili , "r") ; 3d variables h = f->HGT_221_ISBL(:,j,i) t = f->TMP_221_ISBL(:,j,i) u = f->U_221_ISBL(:,j,i) v = f->V_221_ISBL(:,j,i) q = f->SPF_H_221_ISBL(:,j,i) ; 2d variables prc = f->PRECIP(j,i) lat = f->gridlat_221(j,i) lon = f->gridlon_221(j,i) ; time stime = h_at_initial_time ; 01/01/1997 (18:00) <==> MM/DD/YYYY time = grib_stime2itime(stime) ; 1997010118 <== YYYYMMDDHH system ("/bin/rm -f "+fout) ncdf = addfile (fout, "c") ncdf_at_title = "NARR" ncdf_at_yyyymmddhh = time ncdf_at_time_string = stime ncdf_at_lat = lat ncdf_at_lon = lon ncdf_at_source = fili ncdh_at_creation_date = systemfunc("date") ncdf->HGT = h ncdf->TMP = t ncdf->U = u ncdf->V = v ncdf->Q = q ncdf->HGT = prc end The above could be made more efficient and work on multiple files. good luck D _______________________________________________ ncl-talk mailing list ncl-talk_at_ucar.edu http://mailman.ucar.edu/mailman/listinfo/ncl-talkReceived on Wed Dec 21 2005 - 13:50:28 MST
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