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[netCDF #UUU-464946]: Using netCDF data for hydrology

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  • Subject: [netCDF #UUU-464946]: Using netCDF data for hydrology
  • Date: Mon, 26 Sep 2011 04:41:48 -0600
> We are trying to set up a snowmelt and rainfall runoff model for a basin
> in CA.  We will be using the Army Corps of Engineers HEC-Hydrologic
> Modeling System which only reads .dss files.  We can create .dss files
> from asci files.  The problem is the all of the different types of data
> comes in different grid types, sizes and projections.  We are trying to
> write a program that will take in all types, convert it to .dss and feed
> it into the model with minimal human intervention.
> 
> We downloaded Quantitative Precip Estimate and QPForecast data.  I also
> downloaded FAN and ran nc2text.  I
> 
> I lot of data ran on the screen but I could not figure out how to write an
> ascii file.  I tried nc2text filename.nc filename.asc   and filename.out
> and filename.txt etc etc.  How do I write a file?
> 
> I am trying to determine for QPF data -  What is the cell size,
> coordinates of the lower left corner or upper left.  (I understand
> meteorologists reference the center of the grid cell and hydrologist
> use the lower left corner.)  What is the projection, 0,0 coordinates,
> is it HRAP, Polar, square, degree x degree, meters etc.
> 
> Thanks for your assistance!
> 
> Ted Cassidy
> Dewberry Engineers
> 916 380-3775
> 
> Visit Dewberry’s website at www.dewberry.com
> 
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Howdy Ted!

I'm afraid I cannot be of much help in this situation. I am not familiar with 
dss files, or the tools that you mention. If you use the ncdump command, you 
can convert a netCDF file to text, but this may not be a format easily digested 
by your other programs, and still does not deal with the problems of 
projections and grids. As far as I know, unless the data sets are part of a 
well-formulated set of conventions (like the CF conventions), there will not be 
a general way of converting from one grid to another.

Thanks,

Ed

Ticket Details
===================
Ticket ID: UUU-464946
Department: Support netCDF
Priority: Critical
Status: Closed