I have a shapefile containing around a hundred points (lat/longs). And, I have a shapefile that contains a polyline representing a river. The river is somewhat horizontal (runs east to west) but meanders quite a bit. I am trying to compute how far a point lies to the north or south of the river in meters.
So far I have used the ArcGIS Near tool. My understanding of this tool is that it computes the shortest/perpendicular distance from the closest part of the near feature (in my case the river/polyline). Since the river is not perfectly horizontal, these distances will contain a horizontal component.
How should I compute how far a point lies north or south from the river (i.e. no horizontal component and only vertical distance from the nearest point on the river)?