NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.

To learn about what's going on, see About the Archive Site.

Re: [netcdfgroup] "Advanced Hydrologic Precipication Analysis" grid as CF-compliant NetCDF file?

On 12/17/10 1:45 PM, Rich Signell wrote:

NetCDF folks,

We are looking for a netcdf file that contains the lon/lat values and
perhaps the grid_mapping parameters for the precip data available
from:

http://water.weather.gov/precip/download.php

You can download gridded precip data as NetCDF, but the files do not
contain the lon/lat values, and no such netcdf "grid" file seems
available on the site.   There is a Shapefile with all the lon/lat
points that we could convert to NetCDF, but surely someone must have
already done this, and perhaps even added the x,y coordinates and the
polar_stereographic parameters in a grid_mapping to make it all
CF-compliant?

Thanks,
Rich
Rich: I think this is the info you need (from http://www.nws.noaa.gov/oh/hrl/distmodel/hrap.htm)
"The HRAP grid is defined in the plane of a polar stereographic map projection with the following parameters: longitude of the projection center = -105, standard (true) latitude = 60 N. A spherical earth of radius 6371.2 km is assumed in defining the HRAP coordinate system. Using "ster" as the third argument to the xmrgtoasc.c program generates header information in Polar Stereographic coordinates with units of meters. The "hrap" argument generates header information in HRAP units. These Polar Stereographic coordinates are related to HRAP coordinates as follows: 

    xster=hrapx*4762.5 - 401*4762.5
    yster=hrapy*4762.5-1601*4762.5"

would be nice if they included this metdata in the netcdf file....

-Jeff
  • 2010 messages navigation, sorted by:
    1. Thread
    2. Subject
    3. Author
    4. Date
    5. ↑ Table Of Contents
  • Search the netcdfgroup archives: