How to make features illuminate an underlying basemap

Sure, we can make features look like they are glowing. But how can we make them look like they are casting light on the basemap below? Here’s a silly little trick using crafty symbology and blend modes in ArcGIS Pro. In this case we’ll use glorious stork migration paths, from Movebank.

The Gist:

1. Create a nighttime version of your basemap by adding the World Hillshade Dark layer with an overlay blend. Duplicate as-needed.
2. Illuminate the basemap by giving the line features a very thick gradient stroke with white in the middle fading to transparent white at the edges, and an overlay blend.
3. Style another copy of the line features however you want.

Here’s a three-minute how-to if you want to walk through it with me. Try it with any line (or point) data you like…

Thanks for tuning in! I hope it’s useful to you at some point and your maps get a jolt of illumination. Feel free to share your work as we’d all love to see what you come up with!

Love, John