Transverse Mercator Projection

cartography

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July 14, 2026

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The Transverse Mercator projection is a variation of the Mercator projection, a cylindrical map projection introduced by Gerardus Mercator in 1569. In this projection, the cylinder is tangent to the Earth along a chosen meridian, rather than along the Equator. This treatment is advantageous for creating maps that are elongated in the north-south direction.1

The standard Mercator projection represents meridians as parallel vertical lines and parallels of latitude as horizontal lines that increase in spacing away from the Equator. This makes it useful for navigation charts as straight lines represent constant true bearings. However, it significantly distorts areas farther from the Equator, making them appear disproportionately large. All map projections involve some distortion, and those covering the entire Earth have significant distortions.23

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Geographic and plane coordinate systems
…long in north–south dimension, the Transverse Mercator is generally used, while for those long in east–west direction, the Lambert conformal (intersecting cone) projection is usually employed. In the case of large regions, two or more zones may be established to limit distortions. Positions of geodetic control points have been computed…
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…long in north–south dimension, the Transverse Mercator is generally used, while for those long in east–west direction, the Lambert conformal (intersecting cone) projection is usually employed. In the case of large regions, two or more zones may be established to limit distortions. Positions of geodetic control points have been computed…
Read More