Map Projection Families

Map projectionMap ProjectionMap projections are mathematical transformations that convert the three-dimensional surface of the Earth onto a two-d... families group the hundreds of known map projections into categories based on the geometric surface used to transform spherical coordinates into planar coordinates. The three primary families are cylindrical, conic, and azimuthal, each named for the developable surface—cylinder, cone, or plane—conceptually wrapped around or touching the globe. Cylindrical projections (such as Mercator and Transverse Mercator) unroll the globe onto a cylinder. They are well suited for equatorial regions and navigational charts because they can preserve angles (conformality). Conic projections (such as Albers Equal-Area and Lambert Conformal Conic) project onto a cone tangent or secant to the globe, excelling at mid-latitude regions like the continental United States or Europe. Azimuthal projections (such as Stereographic and Lambert Azimuthal Equal-Area) project onto a plane, and are often used for polar regions or hemispheric views centered on a point of interest. No projection can simultaneously preserve area, shape, distance, and direction, so the choice of projection family depends on what property matters most for the map’s purpose. GISGISGeographic Information Systems (GIS) enable users to analyze and visualize spatial data to uncover patterns, relation... software like ArcGISArcGISArcGIS is a leading GIS platform offering tools for spatial analysis, mapping, and data visualization. It serves a wi... Pro and QGISQGISQGIS is a user-friendly, open-source GIS platform that provides tools for geospatial data analysis, mapping, and inte... provide extensive projection libraries with on-the-fly reprojection. Understanding projection families helps cartographers and GIS analysts select transformations that minimize distortion for their specific geographic extent and analytical needs.