Re: Rotated pole coordinate system

NCL will plot correctly.

>From the NCL home page: http://www.ncl.ucar.edu/

Click "Application examples" on the yellow bar.
Under "Models, click "CCSM:POP"

The POP ocean model is a "rotated pole" grid.

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"

  f = addfile("POP.nc","r")
  t = f->TEMP

  lat2d = f->TLAT ; rotated coordinates
  lon2d = f->TLONG
  t_at_lon2d = lon2d
  t_at_lat2d = lat2d

  wks = gsn_open_wks("ps","popscal") ; open a ps file
  res = True
  res_at_gsnAddCyclic = True
  plot = gsn_csm_contour_map_ce(wks,t(0,0,:,:),res)
 
On Fri, 11 Jul 2008, alberto maurizi wrote:

>
> I'm quite new to NCL and I'm exploring its capabilities.
>
> The output of our meteo-chem model is given in a "rotated pole"
> (RP) coordinate system (CS). This means that the "north pole" of
> the CS is located in a different location with respect to the
> geographical one. In the RP frame, the grid is regular which
> means that is non-regular in the geographycal system (GS).
>
> The RP CS is fairly common and is also defined in the CF
> convention for NetCDF so I expect NCL to be able to deal with
> it.
>
> Should I expect that a CF complianf netcdf file with RP CS be
> plotted correclty?
>
> Alberto
>
> Below there is the ncdup -h of a typical file
>
> netcdf qq {
> dimensions:
> lon = 110 ;
> lat = 95 ;
> time = UNLIMITED ; // (24 currently)
> variables:
> double lon(lon) ;
> lon:long_name = "longitude" ;
> lon:units = "degrees_east" ;
> lon:standard_name = "longitude" ;
> double lat(lat) ;
> lat:long_name = "latitude" ;
> lat:units = "degrees_north" ;
> lat:standard_name = "latitude" ;
> char rotated_pole ;
> rotated_pole:grid_mapping_name = "rotated_latitude_longitude" ;
> rotated_pole:grid_north_pole_latitude = 36.5 ;
> rotated_pole:grid_north_pole_longitude = -170.25 ;
> double time(time) ;
> time:units = "day as %Y%m%d.%f" ;
> float CO(time, lat, lon) ;
> CO:long_name = "CO" ;
> CO:units = "g/m2" ;
> CO:grid_mapping = "rotated_pole" ;
> CO:_FillValue = -9.e+33f ;
> [...]
>
>
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Received on Fri Jul 11 2008 - 11:17:52 MDT