Polar Stereographic Projection

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08-27-2012 01:27 PM
GabrielMcMahan
New Contributor
I was asked to create a map in a custom projection for meteorological data and I am having some trouble figuring out how to specify the projection in ArcGIS.

This was the description of the projection. 

"The map projection we use is a local polar stereographic one.

map_proj = 'polar',
ref_lat   =  59.20,                <------------------- projection point
ref_lon   = -145.3,              <------------------- projection point
truelat1  =  60.1,
truelat2  =  90.0,
stand_lon = -149.3"

I've tried a few things, but I can't seem to get the map to match some hard copies he already has.  Does anyone have any insight into using this information in ArcGIS?

Thanks
Gabe
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MelitaKennedy
Esri Notable Contributor
Hi Gabe,

I'm wondering if this data is actually using a rotated world. Perhaps 59.2, -145.3 is the equivalent of the north pole, with -149.3 showing where the central meridian runs (which will be either north or south from the center point) and 60.1 is a standard parallel on the rotated world. 

Hmm, according to this tutorial:

stand_lon = longitude/meridian parallel to the y-axis.
truelat1,2 = standard parallels (2 is only used for lambert conformal conic)
ref_lat, ref_lon = set the center of the displayed data

Have you tried using Stereographic_North_Pole with:

central meridian = -149.3
standard parallel 1 = 60.1

Do you have the sphere's radius value? Because that will throw off the calculations if you're using a standard GCS like WGS84.

Melita
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GabrielMcMahan
New Contributor
thanks for the input Melita.  I did try

central meridian = -149.3
standard parallel 1 = 60.1

and it is pretty close to the example map, however there is a slight counter clockwise rotation in my system compared to the example map.  I did use WGS84, so there is a good chance that the GCS is my problem.
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