The Tobler cylindrical I projection is a compromise cylindrical map projection. It was developed and introduced by Waldo Tobler in 1997 as his first simpler alternative to the Miller cylindrical projection. As is the case with the Miller projection, distortion is severe at the poles. This projection is a bit smaller than the Miller projection, but they are almost identical between 45° north and south latitudes.
The Tobler cylindrical I projection is available in ArcGIS Pro 2.5 and later and in ArcGIS Desktop 10.8 and later.
The subsections below describe the Tobler cylindrical I projection properties.
The Tobler cylindrical I projection is cylindric. The meridians are equally spaced straight lines. Parallels and both poles are straight lines, perpendicular to meridians and the same length as the equator. The spacing between parallels perceptually grows from equator to poles. The graticule is symmetric across the equator and the central meridian. The height-to-width ratio of the whole map is 0.71, slightly less than the Miller cylindrical projection.
This projection is neither conformal nor equal-area. Shapes, areas, distances, directions, and angles are all generally distorted. Distortions are minimal in equatorial areas and become severe in polar areas. Distortion values are symmetric across the equator and the central meridian.
This projection can be used for general world maps not requiring accurate areas, and whose phenomena change with longitude. But its use is not recommended due to extreme distortion in polar regions.
This projection is supported on spheres only. For an ellipsoid, the semimajor axis is used for the radius.
Tobler cylindrical I parameters are as follows:
- False Easting
- False Northing
- Central Meridian
Tobler, W. (1997). "Alternatives to Miller's projection." Cartography and Geographic Information Science, 24 (2), p. 110-112. DOI:10. 1559/152304097782439358