topic Re: Equal Area Projection that centers the Philippines in Coordinate Reference Systems Questions

Equal Area Projection that centers the Philippines

AnthonyWhaley — Mon, 25 Nov 2019 03:19:12 GMT

I'm making a map tracking my wife's family migration from the Phillippines to other parts of the world (primarily the US). I want the map to be an equal area projection, but also center south Asia as the center longitude. I'm working in ArcGIS Pro, but still have access to ArcMap if needed. Any suggestions on which coordinate system to choose?

Re: Equal Area Projection that centers the Philippines

JuanSantos — Tue, 22 Jun 2021 08:01:24 GMT

Hi https://community.esri.com/migrated-users/384253

It is advisable to use the WGS 84 coordinate system, I leave a technical link: https://pro.arcgis.com/es/pro-app/help/mapping/properties/specify-a-coordinate-system.htm

You can also choose the coordinate system of your main shape, or use a geodatabase to maintain the same coordinate system.

I hope it helps.-

Re: Equal Area Projection that centers the Philippines

AnthonyWhaley — Mon, 25 Nov 2019 16:10:12 GMT

Hi Juan, thanks for following up. I didn't realize how easy it was to change the central meridian on any coordinate system.

One other question, I have is working with the XY to Line tool and how the lines are drawn with different coordinate systems? I am trying to have these lines "wrap" around the projection, not go over the north pole. Any thoughts?

This is in Equal Area World with 150 longitude as the central meridian. Shouldn't the lines travel across the Pacific, not up and through the North Pole?

Re: Equal Area Projection that centers the Philippines

JuanSantos — Mon, 25 Nov 2019 18:05:37 GMT

Hi! Anthony Whaley

It is advisable to use planar coordinates.

I leave you the following technical links:

Georeferencing and coordinate systems: https://resources.arcgis.com/help/getting-started/articles/026n0000000s000000.htm

Projection types: http://desktop.arcgis.com/arcmap/latest/map/projections/projection-types.htm#ESRI_SECTION2_C5B91D868CFE4FD48814769C74CC183F

Cylindrical equivalent: http://desktop.arcgis.com/es/arcmap/latest/map/projections/cylindrical-equal-area.htm

Conical projections: http://desktop.arcgis.com/es/arcmap/latest/map/projections/conic-projections.htm

Planar Projections: http://desktop.arcgis.com/es/arcmap/latest/map/projections/planar-projections.htm

I hope it helps.-

Re: Equal Area Projection that centers the Philippines

MelitaKennedy — Tue, 26 Nov 2019 01:09:25 GMT

The lines are the geodesic lines--the shortest path on the ellipsoid, so more like what an airplane would fly. If you want lines that are direct in that projected coordsys you're using, you need to build planar lines. You may need to project the source/target points to that projected coordsys.

Re: Equal Area Projection that centers the Philippines

BojanŠavrič — Tue, 26 Nov 2019 19:31:45 GMT

Antony, you could also use customize azimuthal equidistant projection, and centered on the origin point in the Phillippines. This way your lines between origin and destination will be straight and shortest. Unfortunately, your map will look a bit unusual... Check it out.