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I have a NetCDF file of ice velocities of the Greenland ice sheet but they are in polar stereographic coordinates (y: -655750 to -3355750 and x: -639750 to 855750 meters).

I am wondering if there exists a command in NCO or CDO that can convert from NSIDC polar stereographic north (which is in meters) to WGS84 degrees. I checked this ncremap module, but what is this 1x1.nc file in the NCO documentation? Is it just some random data in the WGS84 lat/lon coordinates? Does it have to be the same extent as the original data? Will this module automatically recognize the NSIDC Sea Ice Polar Stereographic North projection in the original file?

Below is some info about the NetCDF file:

Format:
           netcdf4
Global Attributes:
           Conventions                = 'CF-1.6'
           product_version            = 'ESP 2.1'
           date_created               = '2018-06-25'
           title                      = 'greenland_iv_500m_s1_20171228_20180228_v1_0'
           institution                = 'ENVEO IT GmbH'
           summary                    = 'Greenland IV from Sentinel-1'
           project                    = 'ESA Greenland Icesheet CCI'
           tracking_id                = '4d99b8ce-9418-4a84-aa47-92d0dd90a746'
           time_coverage_start        = '2017-12-28'
           time_coverage_end          = '2018-02-28'
           sensors_used               = 'Sentinel-1'
           methods_used               = 'Offset-tracking'
           velocity_projection_method = 'Horizontal Flow'
Dimensions:
           y = 5401
           x = 2992
Variables:
    crs                                
           Size:       1x1
           Dimensions: 
           Datatype:   int32
           Attributes:
                       grid_mapping_name                     = 'polar_stereographic'
                       standard_parallel                     = 70
                       straight_vertical_longitude_from_pole = -45
                       false_easting                         = 0
                       false_northing                        = 0
                       unit                                  = 'meter'
                       latitude_of_projection_origin         = 90
                       spatial_ref                           = 'PROJCS["WGS 84 / NSIDC Sea Ice Polar Stereographic North",GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]],PROJECTION["Polar_Stereographic"],PARAMETER["latitude_of_origin",70],PARAMETER["central_meridian",-45],PARAMETER["scale_factor",1],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","3413"]]'
    y                                  
           Size:       5401x1
           Dimensions: y
           Datatype:   double
           Attributes:
                       units         = 'm'
                       axis          = 'Y'
                       long_name     = 'y coordinate of projection'
                       standard_name = 'projection_y_coordinate'
    x                                  
           Size:       2992x1
           Dimensions: x
           Datatype:   double
           Attributes:
                       units         = 'm'
                       axis          = 'X'
                       long_name     = 'x coordinate of projection'
                       standard_name = 'projection_x_coordinate'
    land_ice_surface_velocity_magnitude
           Size:       2992x5401
           Dimensions: x,y
           Datatype:   single
           Attributes:
                       _FillValue   = 3.402823466385289e+38
                       units        = 'meter day-1'
                       description  = 'magnitude of horizontal ice velocity'
                       grid_mapping = 'crs'
                       coordinates  = 'y x'

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