polar stereographic projection

polar stereographic projection

A projection formed by positioning a flat sheet of paper tangential over one pole on the reduced earth and projecting the latitude and longitude graticule onto the paper from a light source positioned at the other pole. In this projection, the scale is correct only at the pole of projection and expands away from it. It has a constant value over the whole chart. Meridians appear as straight lines radiating from the point of projection, and latitudes appear as concentric circles. The rhumb lines are curves concave to the pole of projection. The great circles are also curves concave to the pole of projection except for meridians, which are straight lines that are both great circles and rhumb lines. The projection finds its use in the preparation of plotting, topographical maps, radio aids, and meteorological charts for use in the polar regions.