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19991107: proj,garea

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  • Subject: 19991107: proj,garea
  • Date: Mon, 08 Nov 1999 09:29:26 -0700
>From: Matt Fearon <address@hidden>
>Organization: Desert Research Institute
>Keywords: 199911072325.QAA10931

>Hi Steve,
>
>I am trying to use gempak to output model data that has
>uniform grid spacing; having same latitude and longitude
>spacing throughout. Seems like the settings in proj and 
>garea w/in the gdlist program should be able to perform 
>this ? I was attempting to do this with proj set to 
>lea (Lambert Equal Area), but I think the angles I was 
>using were incorrect. Any suggestions you may have 
>would be great.
>
>Thank you,
>Matt Fearon
>address@hidden
>


Matt,

If your grid has latitudes equally spaced and longitudes equally spaced,
then this is a CED (Cylindrical equidistant) projection grid. Set PROJ=CED.

The lambert projection is a connical projection.

If you data is a CED projection, then if you display it on a CED projection
map, then the rows and columns will look rectangular.

Similarly, the LCC grids like the eta 211 look rectangular when plotted
on a LCC map, but the rows and columns curve on a different projection.

Steve Chiswell