[cf-satellite] Question regarding gridded products

• To: cf-satellite <cf-satellite@xxxxxxxxxxxxxxxx>
• Subject: [cf-satellite] Question regarding gridded products
• From: ghansham sangar <ghanshamsangar@xxxxxxxxx>
• Date: Wed, 25 Jan 2012 08:21:43 +0530

R/Sir

This example has been taken from CF 1.6 document. As pointed below, do we
need to create first create 'x' and 'y' variables and fill values in kms of
each X and Y coordinate in 'x' and 'y' variables, respectively. And then
create variables 'lat' and 'lon' and fill in the values of latitude and
longitude coordinates in 'lat' and 'lon' variables respectively.
It then simply means adding redundant information because we can always
derive latitude/longitude values from X and Y given the projection
parameters.
Can anyone kindly provide some sample product following CF conventions in
LCC/Mercator projection.
It will be of great help.

  dimensions:
   y = 228;
   x = 306;
   time = 41;

variables:
  int Lambert_Conformal;
    Lambert_Conformal:grid_mapping_name = "lambert_conformal_conic";
    Lambert_Conformal:standard_parallel = 25.0;
    Lambert_Conformal:longitude_of_central_meridian = 265.0;
    Lambert_Conformal:latitude_of_projection_origin = 25.0;
  double y(y);
    y:units = "km";
    y:long_name = "y coordinate of projection";
    y:standard_name = "projection_y_coordinate";
  double x(x);
    x:units = "km";
    x:long_name = "x coordinate of projection";
    x:standard_name = "projection_x_coordinate";
  double lat(y, x);
    lat:units = "degrees_north";
    lat:long_name = "latitude coordinate";
    lat:standard_name = "latitude";
  double lon(y, x);
    lon:units = "degrees_east";
    lon:long_name = "longitude coordinate";
    lon:standard_name = "longitude";
  int time(time);
    time:long_name = "forecast time";
    time:units = "hours since 2004-06-23T22:00:00Z";
  float Temperature(time, y, x);
    Temperature:units = "K";
    Temperature:long_name = "Temperature @ surface";
    Temperature:missing_value = 9999.0;
    Temperature:coordinates = "lat lon";
    Temperature:grid_mapping = "Lambert_Conformal";

regards
Ghansham