[Proj] Have LCC center terms, need PROJ.4 terms

Andre Joost andre+joost at nurfuerspam.de
Mon Feb 10 15:07:38 EST 2014

Am 09.02.2014 21:59, schrieb Hamish:
> Hi,
> I'm working with some weather model (WRF) output and I'll like to
> import the results into proj4-aware software (gdal or grass gis).
> The LCC model domain specification takes center of region lat/lon as
> input, not +lat_0, +lon_0. The values I've been given for +lat_1 and
> +lat_2 are equal, and near to +lon_0. That doesn't look quite
> right but the model seems happy enough with it:
> the values I was given:
> CEN_LAT = 40.26405f ;
> CEN_LON = -76.99222f ;
> TRULAT1 = 39.338f ;
> TRUELAT2 = 39.338f ;
> MOAD_CEN_LAT = 39.33799f ;
> STAND_LON = -84.f ;

I guess that should be a LCC 1SP projection with these parameters:
+proj=lcc +lat_1=39.338 +lat_0=39.338 +lon_0=-84 +k_0=1 +x_0=0 +y_0=0 
+ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

> This trial and error gets me to within about 5% (see attatched)

 From the image it is hard to tell what grid line should be right or 
wrong. For lon_0=-84, the 84W should be exactly vertical.

Can you share sample coordinates?

André Joost

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