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APIs

Terrain ServicesAPI Reference

Under Development

Query digital elevation topography models, calculate slope steepness, flow aspects, and retrieve point elevation data.

Terrain Computational Model

The terrain subsystem provides digital elevation queries and runs mathematical gradients to solve slope contours and drainage flows.

GET/v1/terrain/dem

Download digital elevation model (DEM) grids cropped to a bounding box geometry, returned as a georeferenced GeoTIFF.

Request Parameters

ParameterTypeRequiredDescription
bboxstring (array of float)YESGeographic bounding coordinates [MinLon, MinLat, MaxLon, MaxLat] in EPSG:4326.
sourcestringNOThe digital elevation model source. Options: 'SRTM_30M' (default) or 'Copernicus_DEM_30M'.
json
1{
2"status": "success",
3"bbox": [-122.68, 45.51, -122.65, 45.53],
4"source": "SRTM_30M",
5"asset_url": "https://download.velstrom.in/terrain/dem/srtm_t10t_crop.tif"
6}
GET/v1/terrain/slope

Calculate slope steepness (in degrees) for a bounding box area. Computes steepness matrices on the fly using terrain elevations.

Request Parameters

ParameterTypeRequiredDescription
bboxstring (array of float)YESGeographic bounding coordinates [MinLon, MinLat, MaxLon, MaxLat] in EPSG:4326.
sourcestringNOThe digital elevation model source. Options: 'SRTM_30M' (default) or 'Copernicus_DEM_30M'.
json
1{
2"status": "success",
3"bbox": [-122.68, 45.51, -122.65, 45.53],
4"source": "SRTM_30M",
5"asset_url": "https://download.velstrom.in/terrain/slope/srtm_t10t_slope.tif"
6}
GET/v1/terrain/aspect

Calculate slope aspect (downhill direction in degrees, 0-360) for a bounding box area.

Request Parameters

ParameterTypeRequiredDescription
bboxstring (array of float)YESGeographic bounding coordinates [MinLon, MinLat, MaxLon, MaxLat] in EPSG:4326.
sourcestringNOThe digital elevation model source. Options: 'SRTM_30M' (default) or 'Copernicus_DEM_30M'.
json
1{
2"status": "success",
3"bbox": [-122.68, 45.51, -122.65, 45.53],
4"source": "SRTM_30M",
5"asset_url": "https://download.velstrom.in/terrain/aspect/srtm_t10t_aspect.tif"
6}
GET/v1/terrain/elevation

Perform a single-point spatial lookup to retrieve the elevation, slope, and aspect values for a specific coordinate pair.

Request Parameters

ParameterTypeRequiredDescription
latfloatYESLatitude coordinate of target point query.
lonfloatYESLongitude coordinate of target point query.
sourcestringNOThe digital elevation model source (e.g. 'SRTM_30M' or 'Copernicus_DEM_30M').
json
1{
2"status": "success",
3"coordinates": {
4"lat": 45.52,
5"lon": -122.68
6},
7"elevation_meters": 42.84,
8"slope_degrees": 1.25,
9"aspect_degrees": 184.5,
10"source": "SRTM_30M"
11}