If you love Slope Angle Shading and Shaded Relief, then you are a fan of digital elevation models (DEMs) whether you know it or not. 

A DEM is a representation of the bare surface of the earth, with trees, buildings, and other objects stripped away. DEMs are the backbone of digital mapping – they provide the elevation data behind many of CalTopo’s tools and layers. When you want to see how much elevation you’ll gain and lose along a route? The Line Profile will pull from the DEM to build the graph. Looking to highlight areas above treeline? Custom Terrain Shading uses the DEM to shade everywhere above the elevation you choose.

So yeah, we love our DEM at CalTopo. 

DEMs come from a variety of sources, from topographic maps to high resolution LiDAR. We are always on the lookout for newer, high quality elevation data sources and we have a few updates that we are excited to share.

More High Resolution Elevation Data

Higher resolution elevation data means more detailed terrain. Who doesn’t love that? 

In the continental United States, we’ve added more LiDAR coverage, including:

• Death Valley, CA
• Palm Springs, CA
• The rest of Red Rock Canyon National Conservation Area, NV
• Mount Democrat, CO

This update is best seen for yourself. Move the slider on the image below to check out the striking difference between the original lower resolution elevation (left) data and the new high resolution LiDAR (right):

Split image of Mummy Mountain, NV with MapBuilder Topo and slope angle shading. 

Outside the US, we’ve added more LiDAR too. The latest round of updates include: 

• Parts of Antarctica (plus elevation data in general across the whole continent)
• Expanded coverage in New Zealand
• Almost all of Norway 

We’re pretty stoked about this one. Move the slider on the image below to take a look at the level of detail now available for Aoraki (Mount Cook), NZ:

Split image of Aoraki, NZ with Shaded Relief and MapBuilder Overlay. New LiDAR data is on the left and the original lower resolution elevation data is on the right.

To see everywhere we currently have high resolution elevation data, check out our interactive high resolution coverage map.

Existing LiDAR data got an overhaul

This change is subtle but it makes a big difference. We’ve improved how we render our existing LiDAR elevation data, going from 2-meter to 1-meter resolution. 

So what does this mean for you? 

Terrain in those areas is now twice as sharp, so you can zoom in and see much more detail than before. The difference is especially striking when scouting talus fields and trails, such as in the image below showing a boulder field near Mount of the Holy Cross, CO:

Split image of Mount of the Holy Cross, CO with Shaded Relief. New LiDAR data is on the left and the original lower resolution elevation data is on the right.

This upgrade applies everywhere we already had LiDAR coverage, except the Arctic. It’s available online in the web and mobile app.

NEW: LiDAR Coverage

We aim to use the best available elevation data worldwide, but the resolution of that data varies a lot from place to place. Knowing the resolution for a given area can help inform your decision making, especially when it comes to slope and avalanche terrain analysis.

The new LiDAR Coverage overlay shows the resolution of the underlying elevation data, from coarse, low resolution coverage to true 1-meter LiDAR. A simple, fixed color scheme makes it easy to see how much detail is available, so you know the quality of the data you’re working with.

LiDAR Coverage is available to all users on the web and mobile app. To add it to your Overlays list:

1. Open the Map Layers menu and click or tap the gear icon in the top right.
2. Search for “LiDAR Coverage.”
3. Click or tap the checkbox next to the layer name to add it to your overlays.

Learn more in the LiDAR Coverage overlay section of our user guide. 

UPDATED: Terrain Shaded Relief

Last but definitely not least, we’ve updated Terrain Shaded Relief.

Terrain Shaded Relief is now a less exaggerated version of Normal Shaded Relief. This makes it easier to see fine detail on south- and east-facing slopes in particular, which often end up in shadow on other Shaded Relief layers. On its own, Terrain Shaded Relief can reveal abandoned roads, old building sites, and other features that don’t show up on other map layers.

Learn more in the Terrain Shaded Relief section of our user guide.

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We’re committed to offering the best data, tools, and map layers out there, and we’re always working behind the scenes to make CalTopo more powerful. Stay tuned.

Have a question or suggestion for our elevation data? Let us know in the comments below.