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New map projections supported in ArcGIS 10.4

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02-18-2016 12:05 AM
BojanŠavrič
Esri Contributor
4 6 5,904

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
Frequent Contributor

Nice

AdrianWelsh
MVP Honored 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
Regular Contributor

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 on the Projection Engine team at Esri, specializing in coordinate reference systems, datum transformations, and map projections. He is the coauthor of several map projections for world maps and is an enthusiastic lover of the math behind maps.