What I have is a route layer of a river and points layer with associated temperature data (temperature of the river) that were collected using an airplane. The path of the points does not match the path of the river, but the points are in the vicinity of the river. My goal is to calculate river km locations of those points along that river layer. I could do this manually, but there are over 600 points. Is there a way to find locations for all of those points on the route layer that is river?
When it comes to the distance along a linear feature, linear referencing is the way to go.
The first step is to create routes if your feature class is not M-aware. Maybe this is already the case for you as you mentioned "route" in your question.
When you have routes, you just need to use "Locate feature along route" and you have the distance to the line as well as the position on the river for each point.
Depending on the algorithm you want to use for assigning the values to your stream stations there may be several ways to do this. However, I suggest you use Feature Vertices To Points (Data Management) to convert all the vertices of your stream to point. Then, using the Near (Analysis) find the closest point (vertices on the stream) to the temperature points. Finally you need to join the tables to add the desired values to stations on your stream. If you want the values on specific stations (such as 1km , 2km , 3km ...) first you have to create the points on these station (see this:Methods for splitting line features) and then using Feature Vertices To Points get the points and do the near analysis.
