topic Re: Buffering: Planar vs Geodesic measurement mode when data is in GCS in ArcGIS Pro Questions

Buffering: Planar vs Geodesic measurement mode when data is in GCS

Craig_Eissler_Iceman — Mon, 13 Nov 2023 18:46:40 GMT

See excerpt below from the Buffer Help doc.
I'm not certain I completely understand the second bullet.

...Why would this option even be allowed with data in GCS?
...Perhaps I'm not clear on how a distance input in degrees even works..?

However, I did notice that when inputting linear units I get the same result as the data in PCS but using geodesic mode.

Re: Buffering: Planar vs Geodesic measurement mode when data is in GCS

DanPatterson — Mon, 13 Nov 2023 20:18:50 GMT

angular distance is a real thing, but it doesn't mean that the planar distance will be the same at all locations along a path. Picture a line of longitude... buffer it by 1 degree... you end up with a lune. Geodesic buffers should be used. Your "however" shows this

Re: Buffering: Planar vs Geodesic measurement mode when data is in GCS

Craig_Eissler_Iceman — Mon, 13 Nov 2023 20:43:10 GMT

But, if my data is in a GCS, how is it able to use linear units to measure the buffer distance?

For instance -- see below: If my Map is in a GCS and I attempt to Measure in Planar mode, it is grayed-out.
So, is this not the equivalent concept?

Re: Buffering: Planar vs Geodesic measurement mode when data is in GCS

DanPatterson — Mon, 13 Nov 2023 21:15:29 GMT