create lat lon coordinates from projected coordinates

From: Leif Truelsen <truelsen.leif_at_nyahnyahspammersnyahnyah>
Date: Wed Feb 13 2013 - 14:03:27 MST

Hello,

I have data that in a polar stereographic projection. However, there are
no associated latitude and longitude variables, so when I attempt to plot
with ncl I get the errors about not having valid coordinate arrays (e.g.,
check_for_y_lat_coord: Warning: Data either does not contain a valid
latitude coordinate array or doesn't contain one at all.). I think the
most clear solution would be if I created latitude and longitude variables,
no? Can anyone help direct me how to do this, or of the way to
plot/manipulate the data as they are?

Best regards,
Leif

Here's my data:

 dimensions:
   x = 1779;
   y = 1854;
   time = 10;
 variables:
   char polar_stereographic;
     :grid_mapping_name = "polar_stereographic";
     :straight_vertical_longitude_from_pole = 0.0; // double
     :false_easting = 0.0; // double
     :false_northing = 0.0; // double
     :latitude_of_projection_origin = -90.0; // double
     :standard_parallel = -70.0; // double
     :longitude_of_prime_meridian = 0.0; // double
     :semi_major_axis = 6378273.0; // double
     :inverse_flattening = 298.279411123061; // double
     :spatial_ref = "PROJCS[\"NSIDC Sea Ice Polar Stereographic
South\",GEOGCS[\"Unspecified datum based upon the Hughes 1980
ellipsoid\",DATUM[\"Not_specified_based_on_Hughes_1980_ellipsoid\",SPHEROID[\"Hughes
1980\",6378273,298.279411123061,AUTHORITY[\"EPSG\",\"7058\"]],AUTHORITY[\"EPSG\",\"6054\"]],PRIMEM[\"Greenwich\",0,AUTHORITY[\"EPSG\",\"8901\"]],UNIT[\"degree\",0.0174532925199433,AUTHORITY[\"EPSG\",\"9122\"]],AUTHORITY[\"EPSG\",\"4054\"]],PROJECTION[\"Polar_Stereographic\"],PARAMETER[\"latitude_of_origin\",-70],PARAMETER[\"central_meridian\",0],PARAMETER[\"scale_factor\",1],PARAMETER[\"false_easting\",0],PARAMETER[\"false_northing\",0],UNIT[\"metre\",1,AUTHORITY[\"EPSG\",\"9001\"]],AXIS[\"X\",EAST],AXIS[\"Y\",NORTH],AUTHORITY[\"EPSG\",\"3412\"]]";
     :GeoTransform = "-3966250 4450 0 4119400 0 -4450 ";
     :_CoordinateTransformType = "Projection";
     :_CoordinateAxisTypes = "GeoX GeoY";
   float ice(time=10, y=1854, x=1779);
     :_FillValue = -3.4028235E38f; // float
     :grid_mapping = "polar_stereographic";
   double time(time=10);
     :calendar = "365_day";
     :standard_name = "time";
     :units = "hours since 2001-00-00 00:00:00";
   double x(x=1779);
     :standard_name = "projection_x_coordinate";
     :long_name = "x coordinate of projection";
     :units = "m";
     :_CoordinateAxisType = "GeoX";
   double y(y=1854);
     :standard_name = "projection_y_coordinate";
     :long_name = "y coordinate of projection";
     :units = "m";
     :_CoordinateAxisType = "GeoY";

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Received on Wed Feb 13 14:03:38 2013

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