Retrieve SRTM tiles

Last update: Oct. 2016

This service provides a TIFF image with values from the SRTM (Shuttle Radar Topography Mission) Digital Elevation Model.

Available worlwide and for free. WGS 84 projection.

Command:

http://www.webservice-energy.org/mapserv/srtm?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&
BBOX=min_lat,min_lon,max_lat,max_lon&
CRS=EPSG:4326&WIDTH=nb_pix&HEIGHT=nb_pix&LAYERS=srtm_version&FORMAT=image/tiff

with:

  • min_lon: west bound of your bbox
  • max_lon: east bound of your bbox
  • min_lat: south bound of your bbox
  • max_lat: north bound of your bbox
  • nb_pix: size of the image in pixels
  • srtm_version: srtm_s0 (full resolution, 16 bits), srtm_s2 (½ resolution srtm_s0), srtm_s4 (½ resolution srtm_s2), or srmt_s8 (8 bits, ½ res. srtm_s4)

Characteristics:
The webservice enables you to retrieve a map of max 2048 by 2048 pixels. Where SRTM is not defined, i.e. in the water areas, value is -32768 or -2ˆ15. The highest spatial resolution is 5°/6000 pixels, which means that 1 pixel corresponds to 0.000833° (= 3" = 3*1/3600). If you request a pixel size higher than the spatial resolution, an undersampling operator is applied to create a coarser image. Whereas, if the requested pixel size is smaller than the spatial resolution, a bilinear oversampling is applied on the image.

Don't hesitate to explore the webservice-energy.org catalog.

 

Example

Retrieve the SRTM tile over Corsica (right illustration =>)

http://www.webservice-energy.org/mapserv/srtm?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&
BBOX=41.2,8.3,43.2,9.8&
CRS=EPSG:4326&WIDTH=600&HEIGHT=1000&LAYERS=srtm_s0&FORMAT=image/tiff

Click on the image to magnify