Whenever possible, I do route planning with Google Earth. Google Earth’s 3D imagery allows me to fine-tune a route and identify features I might otherwise miss in two dimensions.
But Google Earth is losing the resolution battle with the other imagery powerhouse, ESRI. I’m willing to trade resolution for 3D exploration in many applications, but not all. I want higher resolution imagery for identifying rapids on remote rivers. Here is an example of the difference in resolution, from unusable in Google Earth to unbelievable in ESRI Worldview.
In a perfect world, I would pull ESRI imagery into Google Earth. It might be possible, but if so, they don’t make it easy (no surprise). Here are other ways to work with the ESRI basemap.
My preferred application for drawing routes on ESRI Worldview is CalTopo. If you are unfamiliar with CalTopo, here is a basic introdution. ESRI Worldview is not available in CalTopo by default; you have to load it manually.
- Go to http://caltopo.com/.
2. Select Add New Layer from the menu on the left side of the page and choose Custom Source.
3. In the Custom Source dialog box, provide a name for the layer and paste the url below in the URL Template field. I’ve increased the Max Zoom from the default 16 to 20. Zoom levels above 16 aren’t always available, but if they are, I want them.
If you have a CalTopo account, click the Save To Account link so that you don’t have to repeat this process. Saved layers can be found in the layer menu in the upper right, at the bottom of the list of options, under Your Layers.
Now I can add waypoints at each rapid and identify which side of the river might be easier to portage. At the end of my work in CalTopo, I save the waypoints and portage line segments to be imported into Google Earth and combined with the rest of my existing route work. But you could certainly do all of your route planning within CalTopo.
ESRI Worldview is available at the premium subscription level of GaiaGPS. Select the Layers & Overlays icon from the buttons on the left, then Add Map Layers at the bottom, Satellite Imagery –> World Imagery.
If you don’t have the premium subscription level, you can manually load the ESRI layer. Follow the directions in the Custom Load Google Earth Imagery section of my Gaia tutorial, but use the ESRI URL instead of the Google Earth URL.
My routes are all going to end up in GaiaGPS anyway (so that I can load them onto my phone for the trip), so why not use the Gaia website in the first place? The reason is that Gaia’s web application tile servers are prohibitively slow. GaiaGPS is absolutely the easiest way to work with the ESRI basemap. I just get impatient. The hassle of loading ESRI into CalTopo pays for itself after 10 minutes of mapping.
There are a few easy ways to view the ESRI layer without the ability to add waypoints or routes. These are my go-to in the exploration phase of trip planning.
The direct from ESRI option allows you to determine the date that the imagery was collected. In this case, the river imagery was collected August 31st, 2015. The timestamp is very helpful for anticipating water levels at other summer months.