# Plate carrée

## Description

The plate carrée map projection is an equidistant cylindrical projection with the standard parallel located at the equator. A grid of parallels and meridians forms perfect squares from east to west and from pole to pole. It is one of the simplest and oldest map projections, and therefore its usage was more common in the past. The radius is used as a conversion factor between angular and linear units. Another usage of this projection is to display spatial data stored in a geographic coordinate system, known as the pseudo-plate carrée projection.

The projection was invented by Marinus of Tyre around A.D. 100. It is available in ArcGIS Pro 1.0 and later and in ArcGIS Desktop 8.0 and later.

## Projection properties

The subsections below describe the plate carrée projection properties.

### Graticule

Plate carrée is a cylindrical projection. The meridians and parallels are equally spaced straight lines forming a Cartesian grid of perfect squares in the normal aspect. In this projection, the poles are represented as straight lines across the top and bottom of the grid, the same length as equator. The graticule is symmetrical across the equator and the central meridian.

### Distortion

The plate carrée projection in the normal aspect is equidistant along any meridian and the equator. Shape, scale, and area distortion increase with the distance from the equator. North, south, east, and west directions are always accurate, but general directions are distorted, except locally along the equator. Distortion values are symmetrical across the equator and the central meridian. In oblique aspects, all vertical lines are equidistant when used with sphere-based Earth models.

## Usage

This projection can be used for simple portrayals of the world or regions with minimal geographic data and those not requiring accurate areas. This makes the projection useful for index maps and to map phenomena that change with longitude, for example, time zones. Most often, data in a geographic coordinate system is displayed in a pseudo-plate carrée projection in which the decimal degree values are treated as if they are linear.

## Variants

There are two variants of the plate carrée projection available in ArcGIS:

• Plate carrée is available in ArcGIS Pro 1.0 and later and in ArcGIS Desktop 8.0 and later.
• Plate carrée oblique is available in ArcGIS Pro 2.9 and later and in ArcGIS Desktop 10.8.2 and later.

The plate carrée oblique version supports oblique variations of this projection. Both implementations support sphere-based Earth models and use the semimajor axis and spherical equations for ellipsoids.

## Limitations

The projection is supported on spheres only. For an ellipsoid, the semimajor axis is used for the radius. Some distortion properties are not maintained in oblique aspects or when ellipsoidal-based Earth models are used.

## Parameters

Plate carrée parameters are as follows:

• False Easting
• False Northing
• Central Meridian

Plate carrée oblique parameters are as follows:

• False Easting
• False Northing
• Azimuth
• Longitude Of Center
• Latitude Of Center

## Sources

Snyder, J. P. (1987). Map Projections: A Working Manual. U.S. Geological Survey Professional Paper 1395. Washington, DC: United States Government Printing Office.

Snyder, J. P. (1993). Flattening the Earth. Two Thousand Years of Map Projections. Chicago and London: University of Chicago Press.

Snyder, J. P. and Voxland, P. M. (1989). An Album of Map Projections. U.S. Geological Survey Professional Paper 1453.Washington, DC: United States Government Printing Office.