NIMBO Terrain (Terrarium)

The Nimbo Terrarium layer provides a global Digital Elevation Model (DEM) service, including bathymetry (ocean depth). It delivers raster heightmaps encoded in RGBA tiles, following the historic format initiated by Mapzen.

This service is a high-performance replacement for legacy Mapzen endpoints, designed for 3D rendering engines, broadcast pipelines, and GIS applications requiring the specific Terrarium encoding standard.

Terrarium vs. Terrain-RGB

This endpoint uses the -32768 offset to handle deep ocean bathymetry. If your application expects the standard Mapbox format (-10000), please refer to our Terrain-RGB Documentation.

Example of terrarium encoding over Europe

Same area with RGB DEM encoding

Technical Specifications

Encoding Format

The elevation values are encoded into the Red, Green, and Blue channels of the image tile. This technique allows 3D software (like Blender, Unity, or Three.js) to read elevation data from a standard image texture.

Feature	Details
Service URL	https://prod-data.nimbo.earth/tiles/terrarium/{z}/{x}/{y}?kermap_token=<YOUR_TOKEN>
Format	PNG
Zoom Levels	0 to 13
Coordinate System	Web Mercator (EPSG:3857)
Coverage	Global Land (85°N to 85°S)
Tile Size	256x256 px

Decoding Formula

To parse the altitude in meters from a pixel, apply the specific Mapzen / Terrarium decoding equation:

elevation = (red * 256 + green + blue / 256) - 32768

• Red (R) & Green (G): Encode the integer part of the elevation.
• Blue (B): Encodes the fractional precision.
• Offset (-32768): This significant negative offset allows the format to represent the deepest parts of the ocean (e.g., the Mariana Trench) without using negative pixel values.

Zoom Levels & Resolution

Nimbo provides native terrain tiles up to Zoom Level 13.

While the legacy Mapzen dataset technically offered tiles up to z15, Nimbo’s optimized processing focuses on high-quality data aggregation up to z13 (approx. 19 meters/pixel at the equator).

Handling High Zoom Levels (z14+)

Do not request tiles for z14 or z15 directly; the API will return a 404 error. Instead, configure your mapping library (MapLibre, Leaflet, OpenLayers) to use oversampling. This technique automatically reuses and stretches z13 tiles to display terrain at higher zoom levels without loss of continuity.

Data Provenance & Sources

Originally hosted on AWS Public Datasets (s3.amazonaws.com/elevation-tiles-prod/terrarium/), the Mapzen service was discontinued in 2018.

The Nimbo Terrarium feed is an exact replica of the historic Mapzen elevation dataset.

Nimbo hosts a static copy of the original archives to guarantee absolute backward compatibility for legacy systems and shaders built specifically for this dataset.

As defined in the original Mapzen specifications, this composite dataset includes:

• Global Landmass (30m): primarily based on NASADEM and SRTM v3 (Shuttle Radar Topography Mission) provided by NASA, ensuring consistent mid-latitude coverage.
• High-Resolution Regional Data: We integrate higher precision Local DEMs where available, such as USGS NED/3DEP (USA), CDEM (Canada), and EU-DEM (Europe).
• Bathymetry & Oceans: Unlike many terrain services that clip at sea level, Terrarium includes seafloor topography derived from ETOPO1 (NOAA) and GEBCO, making it ideal for marine visualization.
• Polar Regions: Enhanced coverage for Arctic and Antarctic regions using ArcticDEM and REMA datasets.

Data resolution per location

Terrarium spatial resolution over the world. Source: Tilezen

Data sources by zoom level

DEM data sources by zoom level. Source: Tilezen

zoom	ocean	land	Ground resolution at 0°	Ground resolution at 45°	Ground resolution at 60°
0	ETOPO1	ETOPO1	156543.0	110692.6	78271.5
1	ETOPO1	ETOPO1	78271.5	55346.3	39135.8
2	ETOPO1	ETOPO1	39135.8	27673.2	19567.9
3	ETOPO1	ETOPO1	19567.9	13836.6	9783.9
4	ETOPO1	GMTED	9783.9	6918.3	4892.0
5	ETOPO1	GMTED	4892.0	3459.1	2446.0
6	ETOPO1	GMTED	2446.0	1729.6	1223.0
7	ETOPO1	SRTM, NRCAN in Canada, with GMTED in high latitudes above 60°	1223.0	864.8	611.5
8	ETOPO1	SRTM, NRCAN in Canada, with GMTED in high latitudes above 60°	611.5	432.4	305.7
9	ETOPO1	SRTM, NRCAN in Canada, EUDEM in Europe, with GMTED in high latitudes above 60°	305.7	216.2	152.9
10	ETOPO1, NED Topobathy in California	SRTM, NED/3DEP, ArcticDEM, LINZ, Kartverket, etc.	152.9	108.1	76.4
11	ETOPO1, NED Topobathy in California	SRTM, NED/3DEP, ArcticDEM, LINZ, Kartverket, etc.	76.4	54.0	38.2
12	ETOPO1, NED Topobathy in California	SRTM, NED/3DEP, ArcticDEM, LINZ, Kartverket, etc.	38.2	27.0	19.1
13	ETOPO1, NED Topobathy in California	SRTM, NED/3DEP, ArcticDEM, LINZ, Kartverket, etc.	19.1	13.5	9.6

Integration examples

MapLibre GL JS

Terrarium DEM encoding is not the default encoding expected by MapLibre GL JS. When defining your source, you must explicitly set encoding: "terrarium". Failing to do so will result in incorrect elevation values.

In addition, set maxzoom to 13. This allows the rendering engine to oversample the DEM tiles when users zoom further (z14+), ensuring smooth terrain rendering.

"sources": {
  "nimbo-terrain": {
    "type": "raster-dem",
    "tiles": [
      "https://prod-data.nimbo.earth/tiles/terrarium/{z}/{x}/{y}.png?kermap_token=<YOUR_TOKEN>"
    ],
    "tileSize": 256,
    "encoding": "terrarium",
    "maxzoom": 13
  }
}