[CF-metadata] proposed first non-beta version of CF

[John Caron]

Hi, sorry it took me so long to notice this:

The "polar steregraphic projection" as documented is confusing.

1. I think it should be called "stereographic", since "polar 
stereographic" is often used to mean a stereographic projection whose 
tangent point is the north or south pole.

2. the meaning of the map parameters are unclear. I realize that you are 
following FGDC, but FGDC is pretty frustrating since there is no text 
explaining in more detail what they mean (actually they reference 
Snyders earlier book, but it doesnt have those names).

The following set would be consistent with the reference PROJ4 docs at 
http://www.remotesensing.org/geotiff/proj_list/polar_stereographic.html,

and the reference text by Snyder (Map Projections - A working manual) 
(actually both Snyder books):

Latitude of natural origin  / tangent point
Longitude of natural origin  / tangent point
Scale factor at natural origin  / tangent point
False Easting 
False Northing 

In any case, these names are consistent with FGDC "Stereographic" 
projection:

Stereographic =
Longitude_of_Projection_Center +
Latitude_of_Projection_Center +
False_Easting +
False_Northing

except they forgot the scale factor.

since the polar stereographic is the special case of stereographic with 
lat origin = 90, i think you should just use the stereographic.

So I would reccomend changing the name to "Stereographic", and using the 
FGDC "Stereographic" projection names with the addition of

Scale_Factor_at_Natural_Origin