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20040105: methods to export data in IDV question

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  • Subject: 20040105: methods to export data in IDV question
  • Date: Tue, 06 Jan 2004 16:02:30 -0700
>From: Jeffrey Buler <address@hidden>
>Organization: The University of Southern Mississippi
>Keywords: 200401052341.i05Nf0p2003173 IDV Level II radar

Hi Jeff-

>I use WSR-88D reflectivities to "map" variation in tropospheric migratory bird
>  
>densities as part of my dissertation research.  Currently available raster 
>radar image data does not offer sufficient resolution in reflectivity  to 
>detect subtle differences in migrant density. IDV might expedite my use of 
>Level II data into a usable form in ArcGIS.  I notice IDV has a Jython library
>  
>editor.  Does a Jython method exist to export data from IDV into an ascii 
>table where each pulse volume is identified by a dBZ value and lat-long 
>position?  If not, what parameters hold the lat-long and dBZ values for pulse 
>volumes within a sweep?  I'd appreciate any advice on how to craft a method 
>that can do this.

At present, there is no export format like what you desire.  For a
Level II radar volume, the data are stored as range, azimuth and 
elevation.  The transform to lat/lon/alt is done in a coordinate
system transformation on the fly when the data are displayed.  Are
you looking for a grid at a constant altitude, or constant radar
elevation angle?

>Alternatively, can data be saved in a georeferenced image format (e.g.GeoTIFF)
> ?

Again, since the coordinates are not lat/lon, the data would have
to be transformed and there is no simple solution to take the
volume to lat/lon/alt coordinates.  With a GeoTIFF, you'd lose the
altitude component.  

Don Murray