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20050531: Dx and Dy units in hurricane data

Hi Eric-

I apologize for the delay in responding.  I suggest you send
these inquiries to address@hidden, otherwise they
tend to get lost in my inbox.

Eric Davies wrote:

Hi Don,
I'm trying to get the georeferencing correct for when I convert your hurricane netcdf file into something we can load into a database. From what I can see, its a Lambert Conformal Conic, with Central Meridian of -81E, Latitude_Of_Origin 26N, Standard_Parallel_1 26N, Standard_Parallel_2 26N. 

That looks correct.
What is less clear is the spatial coverage of the grid. The Dx and Dy variables suggest 7437km in each projected direction. That seems rather large, even for the entire extent of the grid. Can you confirm or correct this interpretation? 

Your interpretation is correct,  but the file is wrong.  The
units for Dx and Dy should be meters.  We are automatically
dividing by 1000 to convert to kilometer, that's why they
look correct in the IDV.  We are tracking down the source
of the problem that created the bad netCDF file and also will
be checking the units to make sure we interpret the values
correctly.

Don
*************************************************************
Don Murray                               UCAR Unidata Program
address@hidden                        P.O. Box 3000
(303) 497-8628                              Boulder, CO 80307
http://www.unidata.ucar.edu/staff/donm
        "Time makes everyone interesting, even YOU!"
*************************************************************