Terrain Elevation Discrepancy in Norway Using Cesium Terrain

Cesium ion
1

Hello everyone,

We’ve encountered a roughly 7 m discrepancy between Cesium’s terrain data and a GPS-based device at a specific location in Norway:

  • Latitude: 62.6644114
  • Longitude: 8.5236262

Cesium shows an elevation of about 60 m HAE, but our GPS device reports around 53 m for the same spot. We also tested Google’s terrain service at this coordinate and found a similar ~60 m result, suggesting the underlying DEM data might be off in that region.

Accurate elevation is critical in our application, and we want to figure out how to address or at least quantify this discrepancy. We’d appreciate any suggestions on:

  1. Why these differences might occur (e.g., data sources, datum issues, resolution limits).
  2. How to incorporate more precise local data or otherwise improve vertical accuracy in Cesium.
  3. What others have done to mitigate such discrepancies when building 3D apps.

Any guidance or shared experiences would be greatly appreciated!

2

Hi @Abhishek_Aneja! Thank you for raising this point.

I’ve gone ahead and move your post to the Cesium ion category, so that developers from our data team can take a closer look.

Thanks!

4

Ok, thank you, waiting for the response.

5

Hi,

  1. As you suggested, the data sources used to construct Cesium World Terrain might have issues with resolution or accuracy at that location. Cesium relied on publicly available data sources to construct Cesium World Terrain.
  2. You can always augment Cesium World Terrian by using your own or publicly available terrain data that is more accurate for the given area. See this page for more information about tiling your own terrain data.
  3. How to mitigate may depend on what your application/users are doing with the height data. Can you provide any addtional context about how height is used in your application? We hope that the community can provide some inspiration for you.
1 Like
6

Thank you.

Our use-case is to visualize in real time air devices which are providing and also depict the above ground level distance for them. Another important aspect is to plot and interact with geometries like polyline, polygon etc. while considering the “above ground level” height. For example plotting route for the devices.

All these aspects are highly critical in our application and hence the accuracy of the terrain data matters.This we need in various different countries (essentially worldwide).

Please guide if any mitigations can be done as per our use case.