projection of the polar region is the fact that in theconic projection, the cone is cut and flattenedout to form the map or chart, whereas the gnomonicprojection will appear as is. On the conic projection,points lying close together on either side of themeridian along which the cone is cut will be widelyseparated on the map. The gnomonic projection, onthe other hand, will give a continuous and contiguousview of the areas. Figure 9-23 shows the appearanceof meridians and parallels on a polar gnomonic pro-jection.CONFORMALITYAccording to some authorities, to be conformal,a projection must possess both of the followingcharacteristics:1. It must be a projection on which direction is thesame in all parts of the map. Obviously, for thisdirectional conformality, the meridians (which indicatethe direction of true north) must be parallel, and theparallels (which indicate true east-west direction) mustbe parallel to each other and perpendicular to themeridians.2. It must be a projection on which the distancescale north and south is the same as the distance scaleeast and west.Obviously, none of the projections that we havedescribed have both of these characteristics. The onlyone that has the first characteristic is the Mercator. Onthis projection the meridians are parallel, and theparallels are parallel to each other and perpendicularto the meridians; therefore, the direction of north oreast is the same anywhere on the map. With regard tothe second characteristic, however, a distance of15 degrees (for example) is longer in any part of themap north-south than a distance of 15 degreeseast-west (even in the same part).Figure 9-23.-Meridians and parallels on a polar gnomonic projection.9-20
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