
R-geo users,

I am new at posting, please forgive if I err in protocol.  I have searched the archives, but cannot locate the exact fix to this problem:

I am using a shapefile from NSIDC (sea ice data) with a strange projection.  I believe it is in stereographic UTM, so I would like to be able to plot it in lat/lon or alternatively, project existing lat/lon data (e.g. ship tracks) onto the stereographic projection.   I have tried PBSMapping, sp, maptools and gdal, but no single one seems to fix the 'invalid' projection issue. 

ice <- importShapefile("extent_N_200906_polygon.shp", readDBF=TRUE)
plotMap(ice, projection=TRUE) 
convUL(ice)

 >> Error in convUL(ice) : Missing or invalid projection attribute.

where the .prj file for the associated .shp file is:

PROJCS["Stereographic_North_Pole",GEOGCS["GCS_WGS_1984",
DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137,298.257223563]],
PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],
PROJECTION["Stereographic_North_Pole"],PARAMETER["standard_parallel_1",70],
PARAMETER["central_meridian",-45],PARAMETER["scale_factor",1],PARAMETER["false_easting",0],
PARAMETER["false_northing",0],UNIT["Meter",1]]


Thank you

~ patrick





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