[gradsusr] Reading NetCDF files from AVHRR data

[Lance Steele]

Hello everyone,

 

I would like to open NetCDF files converted from AVHRR data in GrADS.
However, I am running into an error.

 

I am using the sat2netcdf utility from Weather Climate Toolkit (3.4.8)
to convert AVHRR files from the CLASS website (in .GC format) to NetCDF.
However, when I try to open the .nc file in GrADS (v 2.0.a9 running on
Mac OSX), I see the following error:

 

sdfopen ga-> sdfopen AVHRR.GC.nc

Scanning self-describing file:  AVHRR.GC.nc

gadsdf: SDF file has no discernable X coordinate.

 

One reason I think this is the problem is the lack of range.  For
example, when I do an ncdump on the AVHRR file, I see the following:

 

float lon(pixels, scans) ;

lon:long_name = "Longitude" ;

lon:units = "degrees_east" ;

lon:_CoordinateAxisType = "Lon" ;

 

When I do an ncdump on a file that does open in GrADS, I see the
following:

 

float lon(lon) ;

      lon:units = "degrees_east" ;

      lon:long_name = "longitude" ;

      lon:min_value = 120.f ;

      lon:max_value = 139.7997f ;

 

Does GrADS require a range (min_value, max_value) to allow sdfopen to
work?  If so, how can I change the headers for lat and lon to include a
range?

 

Thank you,

 

Lance Steele

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20110525/0d8fc92c/attachment-0003.html