New map projections supported in ArcGIS 10.4

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02-18-2016 12:05 AM
BojanŠavrič
Esri Contributor
4 6 3,427

ArcGIS 10.4 now supports eight small-scale map projections displayed in an animated gif:

Compact Miller
Patterson
Natural Earth
Natural Earth II
Wagner IV
Wagner V
Wagner VII
Eckert-Greifendorff

The Eckert-Greifendorff, Wagner IV and Wagner VII are equal-area projections; the remaining five are compromise projections that try to minimize overall distortion. Sample definitions for the first seven projections are available in the Projected Coordinate Systems\World  and Projected Coordinate Systems\World(Sphere-based) folders.

The Eckert-Greifendorff, Wagner IV and Wagner VII also support ellipsoidal equations. Gnomonic, quartic authalic and Hammer projections are now available in ellipsoidal forms too.

With Eckert-Greifendorff, Hammer ellipsoidal, quartic authalic ellipsoidal, Wagner IV, and Wagner VII, one can select a custom central latitude and create oblique aspects of the projections.

New-Projections-ArcGIS-10.4.gif

ArcGIS 10.4 includes three variants of polar stereographic projection (variant A, B and C – EPSG codes 9810, 9829 and 9830 respectively) and two new variants of Mercator projection (variant A and C – EPSG codes 9804 and 1044 respectively). Mercator variant B (EPSG code 9805) was already included before as Mercator projection.

Mercator variants A and B have origin of northings / Y values at the equator. Variant A uses a scale factor at the equator to reduce overall scale distortion and effectively defines two standard parallels that are symmetric around the equator. Variant B takes a standard parallel and effectively forces the scale factor at the equator to be less than one. Variant C is similar to variant B, but with the addition of a latitude of origin. The origin of northings / Y values occurs at the latitude of origin.

The polar stereographic variant A is centered at a pole. The longitude of origin defines which longitude will be going straight “down” from the North Pole or “up” from the “South Pole” towards the middle of the map. A scale factor reduces the overall scale distortion and effectively defines a standard parallel. The variant B is similar to variant A, only that it takes a standard parallel to reduce the overall scale distortion of the projection and results in a scale factor at the pole of less than one. Variant C is similar to variant B, but with the addition of a latitude of origin. The origin of northings / Y values occurs at the intersection of the latitude of origin and the longitude of origin.

6 Comments
AjitkumarBabar
Occasional Contributor II

Nice

AdrianWelsh
MVP Notable Contributor

This makes me think of XKCD's map projections comic. 

xkcd: Map Projections

Map Projections

JoshuaBixby
MVP Esteemed Contributor

Content wise, great, but the animated GIF isn't working for me.  At first glance I thought it was clever, but then I got frustrated by not being able to get a decent look at a single projection.  Maybe just increasing the cycle time would help, but I am still not sure that wouldn't just create a different issue.

BojanŠavrič
Esri Contributor

Johsua, here are static images from the animated GIF.  Hope this helps!

New-Projections-Static-ArcGIS-10.4.png

JoshuaBixby
MVP Esteemed Contributor

Quite helpful, much easier to visualize, at least for me.

WilliamMortimer
New Contributor III

Good to see the Gif and the static version as well.

I know that comic is great, but I wanted to share a favourite link about map projections as well.

I'm sure most of you might know it anyway:

A Gallery of Map Projections

Have a good day.

William.

About the Author
Bojan is a senior software development engineer at Esri, a co-author of several map projections for world maps, and an enthusiastic lover of the math behind maps.