Decision Support System for Map Projections of Small Scale Data

Quartic Authalic

Usage:*

Other Meridians: Equally spaced quartic (fourth-order equation) curves that are concave toward the central meridian.

Parallels: Unequally spaced straight parallel lines that are perpendicular to the central meridian. Their spacing changes gradually and is greatest near the Equator.

Poles: Points.

Symmetry: About the central meridian or the Equator.

        The Quartic Authalic projection is an equal-area projection. Its scale is true along the Equator, constant along any parallel, and between any pair of parallels equidistant from the Equator. Its distortion is severe near the outer meridians at high latitudes, but less so than on the Sinusoidal projection. It is free of distortion along the Equator. This projection is not conformal or equidistant.

        This projection has one standard parallel, which is by definition fixed at 0º.

*Usage information source:

"Quartic Authalic Projection." 2005. The MathWorks, Inc.. 18 May. 2005 http://www.mathworks.com/access/helpdesk/help/toolbox/map/quarticauthalicprojection.html.

Back to DSS Main Page