Re: [netcdf-java] Can't open Gridded data in NetCDF Java based tools (ToolsUI, IDV) for AZE, LCEA, Mercator projections?

Hi Patrick:

1) we dont have projection classes for "azimuthal_equidistant" and "lambert_cylindrical_equal_area" because ive never seen an actual example before. I will add them when i get a chance.

2) mercator is recognized, but is not handling "scale_factor_at_projection_origin" correctly. i will get a fix for that.

thanks for reporting these problems.

John

On 9/29/2011 1:17 AM, Patrick Sunter wrote:
Hello all,

I've been doing some testing with exporting to NetCDF CF-1 files from
GeoTiff's using GDAL ... and am having problems opening 3 files that
seem to be CF-compliant (IE passed the online compliance checker, and
their projections have the right attributes according to
http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.5/apf.html).

Can anyone see an issue here? The Azimuthal Equidistant and Lambert
Cylindrical Equal Area files refuse to be recognised as gridded data,
whereas the Mercator file loads but IDV/ToolsUI seem unable to
recognise the coordinates properly and display in the right spot.

Files attached and ncdumps listed below.

thanks, Patrick.

--

netcdf melb-small_AZE {
dimensions:
        x = 193 ;
        y = 83 ;
variables:
        char azimuthal_equidistant ;
                azimuthal_equidistant:grid_mapping_name = 
"azimuthal_equidistant" ;
                azimuthal_equidistant:semi_major_axis = 6378137. ;
                azimuthal_equidistant:inverse_flattening = 298.257223563 ;
                azimuthal_equidistant:latitude_of_projection_origin = -37. ;
                azimuthal_equidistant:longitude_of_projection_origin = 145. ;
                azimuthal_equidistant:false_easting = 0. ;
                azimuthal_equidistant:false_northing = 0. ;
                azimuthal_equidistant:proj4 = "+proj=aeqd +lat_0=-37 +lon_0=145
+x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs " ;
                azimuthal_equidistant:spatial_ref = 
"PROJCS[\"unnamed\",GEOGCS[\"WGS
84\",DATUM[\"WGS_1984\",SPHEROID[\"WGS
84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]],AUTHORITY[\"EPSG\",\"6326\"]],PRIMEM[\"Greenwich\",0],UNIT[\"degree\",0.0174532925199433],AUTHORITY[\"EPSG\",\"4326\"]],PROJECTION[\"Azimuthal_Equidistant\"],PARAMETER[\"latitude_of_center\",-37],PARAMETER[\"longitude_of_center\",145],PARAMETER[\"false_easting\",0],PARAMETER[\"false_northing\",0],UNIT[\"metre\",1,AUTHORITY[\"EPSG\",\"9001\"]]]"
;
                azimuthal_equidistant:GeoTransform = "75048.08411999565
30.0083799812434 0 -7954.467523806079 0 -30.0083799812434 " ;
        double x(x) ;
                x:standard_name = "projection_x_coordinate" ;
                x:long_name = "x coordinate of projection" ;
                x:units = "m" ;
        double y(y) ;
                y:standard_name = "projection_y_coordinate" ;
                y:long_name = "y coordinate of projection" ;
                y:units = "m" ;
        byte Band1(y, x) ;
                Band1:long_name = "GDAL Band Number 1" ;
                Band1:grid_mapping = "azimuthal_equidistant" ;

// global attributes:
                :GDAL_AREA_OR_POINT = "Area" ;
                :Conventions = "CF-1.5" ;
                :GDAL = "GDAL 1.9dev, released 2011/01/18" ;
}

===

netcdf melb-small_LCEA {
dimensions:
        x = 192 ;
        y = 81 ;
variables:
        char lambert_cylindrical_equal_area ;
                lambert_cylindrical_equal_area:grid_mapping_name =
"lambert_cylindrical_equal_area" ;
                lambert_cylindrical_equal_area:semi_major_axis = 6378137. ;
                lambert_cylindrical_equal_area:inverse_flattening = 
298.257223563 ;
                lambert_cylindrical_equal_area:longitude_of_central_meridian = 
145.f ;
                lambert_cylindrical_equal_area:false_easting = 0.f ;
                lambert_cylindrical_equal_area:false_northing = 0.f ;
                lambert_cylindrical_equal_area:standard_parallel = -37. ;
                lambert_cylindrical_equal_area:proj4 = "+proj=cea +lon_0=145
+lat_ts=-37 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs " ;
                lambert_cylindrical_equal_area:spatial_ref =
"PROJCS[\"unnamed\",GEOGCS[\"WGS
84\",DATUM[\"WGS_1984\",SPHEROID[\"WGS
84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]],AUTHORITY[\"EPSG\",\"6326\"]],PRIMEM[\"Greenwich\",0],UNIT[\"degree\",0.0174532925199433],AUTHORITY[\"EPSG\",\"4326\"]],PROJECTION[\"Cylindrical_Equal_Area\"],PARAMETER[\"standard_parallel_1\",-37],PARAMETER[\"central_meridian\",145],PARAMETER[\"false_easting\",0],PARAMETER[\"false_northing\",0],UNIT[\"metre\",1,AUTHORITY[\"EPSG\",\"9001\"]]]"
;
                lambert_cylindrical_equal_area:GeoTransform = "75046.57819714122
30.00481221042836 0 -4789456.678646537 0 -30.00481221042836 " ;
        double x(x) ;
                x:standard_name = "projection_x_coordinate" ;
                x:long_name = "x coordinate of projection" ;
                x:units = "m" ;
        double y(y) ;
                y:standard_name = "projection_y_coordinate" ;
                y:long_name = "y coordinate of projection" ;
                y:units = "m" ;
        byte Band1(y, x) ;
                Band1:long_name = "GDAL Band Number 1" ;
                Band1:grid_mapping = "lambert_cylindrical_equal_area" ;

// global attributes:
                :GDAL_AREA_OR_POINT = "Area" ;
                :Conventions = "CF-1.5" ;
                :GDAL = "GDAL 1.9dev, released 2011/01/18" ;
}

=====

(This Mercator does actually load, but then doesn't project properly)

netcdf melb-small_M-1SP {
dimensions:
        x = 192 ;
        y = 81 ;
variables:
        char mercator ;
                mercator:grid_mapping_name = "mercator" ;
                mercator:semi_major_axis = 6378137. ;
                mercator:inverse_flattening = 298.257223563 ;
                mercator:longitude_of_projection_origin = 145.f ;
                mercator:scale_factor_at_projection_origin = 1.f ;
                mercator:false_easting = 0.f ;
                mercator:false_northing = 0.f ;
                mercator:proj4 = "+proj=merc +lon_0=145 +k=1 +x_0=0 +y_0=0
+datum=WGS84 +units=m +no_defs " ;
                mercator:spatial_ref = "PROJCS[\"unnamed\",GEOGCS[\"WGS
84\",DATUM[\"WGS_1984\",SPHEROID[\"WGS
84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]],AUTHORITY[\"EPSG\",\"6326\"]],PRIMEM[\"Greenwich\",0],UNIT[\"degree\",0.0174532925199433],AUTHORITY[\"EPSG\",\"4326\"]],PROJECTION[\"Mercator_1SP\"],PARAMETER[\"central_meridian\",145],PARAMETER[\"scale_factor\",1],PARAMETER[\"false_easting\",0],PARAMETER[\"false_northing\",0],UNIT[\"metre\",1,AUTHORITY[\"EPSG\",\"9001\"]]]"
;
                mercator:GeoTransform = "93968.49658325009 37.56813175897275 0
-4422925.417953242 0 -37.56813175897275 " ;
        double x(x) ;
                x:standard_name = "projection_x_coordinate" ;
                x:long_name = "x coordinate of projection" ;
                x:units = "m" ;
        double y(y) ;
                y:standard_name = "projection_y_coordinate" ;
                y:long_name = "y coordinate of projection" ;
                y:units = "m" ;
        byte Band1(y, x) ;
                Band1:long_name = "GDAL Band Number 1" ;
                Band1:grid_mapping = "mercator" ;

// global attributes:
                :GDAL_AREA_OR_POINT = "Area" ;
                :Conventions = "CF-1.5" ;
                :GDAL = "GDAL 1.9dev, released 2011/01/18" ;
}


_______________________________________________
netcdf-java mailing list
netcdf-java@xxxxxxxxxxxxxxxx
For list information or to unsubscribe, visit: 
http://www.unidata.ucar.edu/mailing_lists/

  • 2011 messages navigation, sorted by:
    1. Thread
    2. Subject
    3. Author
    4. Date
    5. ↑ Table Of Contents
  • Search the netcdf-java archives: