Switzerland Elevation Model

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Swiss DTM. Image showing elevations from the 20m grid model. Data source: Bundesamt für Landestopografie swisstopo
Coverage of the Swiss DTM - here shown as polygons for the about 40000 tiles each 1km x 1km forming the DTM.
Image: 3 different elevation models (SwissALTI3D, CopernicusDEM and NASADEM) and 2 wind turbines close to Entlebuch, Switzerland.

Introduction

The Switzerland Elevation Model (SwissALTI3D) is a digital terrain model (Digitales Geländemodell, DGM) produced by SwissTopo - the Swiss Bundesamt for Landestopografie. The dataset is an accurate digital terrain model developed as a part of a 6-year data-collection process - and being build from airborne laser-scans and stereo-imagery. Two Swiss elevation models are delivered with windPRO: one at 5m resolution and one at 20m resolution. The original models are available at maximum resolution of 0.5m and 2m, however, the highest resolution model in windPRO version is resampled by EMD to obtain a slightly coarser resolution - 5m. This is done in order for the data to be operational for the larger domains needed in the context of wind farm analysis and wind flow modelling. The resampling is made based on 2m data using a bi-linear interpolation algorithm. Data made available by EMD represents the data status of October 2021.

Dataset Overview

  • Spatial Coverage: Switzerland
  • Resolution: 5m and 20 m in windPRO (original data in 0.5m and 2.0m grid resolution)
  • Data-type: Digital Terrain Model (DTM)
  • Coordinate system: Swiss coordinate system (LV95 LN02) - EPSG 2056
  • Version: Data downloaded in October 2021
  • Accuracy:
    • The accuracy depends on the data-source. The following statement on accuracy is given as a one-sigma estimate for all 3 dimensions (see more at the links below):
      • LiDAR: Newest data: 0.3m, Other data (below 2000m agl): 0.5m
      • Elevations derived from stereo-correlation (above 2000m agl): 1.0m - 3.0m
      • Manually corrected data (single points, edge-lines and areas): 0.1m - 1.0m

More on Model Acurracy

Vertical accuracy within the native 2m resolution dataset is stated to be ±0.3m to ±0.5m for elevations below 2000m agl. The acurracy of the derived 5m and 20m models delivered with windPRO were evaluated on the 58 wind turbine locations in Switzerland. For the evaluation of accuracy, we are taking the 2m model as reference data (ground truth) and then evaluate accuracy at the turbine positions. For the 5m model, the deviation from the 2m model was an average of -0.02m and the standard deviation was 0.15m. A comparison with other popular DTM/DSM's and the 20m dataset are shown in the table below.

DEM accuracy at 58 wind turbines locations in Switzerland - evaluated as the deviation (in meters) from the Swiss 2m model.
Parameter Swiss-5m Swiss-20m CopernicusDEM-30m NASADEM-30m SRTM1-30m AW3D30-30m EUDEM-1.0-30m EUDEM-1.1-30m
Mean -0.02 -0.35 -1.02 -1.46 -2.58 2.00 -3.09 -5.04
Standard Deviation 0.15 0.61 1.87 3.02 2.84 2.57 5.50 5.48
Minimum -0.58 -2.21 -7.72 -11.40 -11.59 -2.44 -22.97 -24.52
Maximum 0.28 1.32 3.66 3.40 3.41 14.30 4.83 2.73

Availability from within WindPRO

The data are available directly from within windPRO in 5m and 20-meter grid resolution. The data can be accessed from the online-services in the following objects:

  • Line Object (with purpose to height contour lines)
  • Elevation Grid Object

License and Attribution

The product belongs to the open geo-data of Switzerland. The data have been licensed under a national open data policy based on the following legal framework:

  • Bundesgesetz über Geoinformation (Geoinformationsgesetz GeoIG SR 510.62) Art. 10 ff
  • Verordnung über Geoinformation (Geoinformationsverordnung GeoIV SR 510.620) Art. 20 ff
  • Verordnung des VBS über die Gebühren des Bundesamtes für Landestopografie (GebVswisstopo SR 510.620.2)

Please read and accept the usage-conditions before use - and be aware a proper attribution is required when using this dataset, such as:

Source: 
 - Bundesamt für Landestopografie swisstopo
 - Office fédéral de topographie swisstopo
 - Ufficio federale di topografia swisstopo
 - Uffizi federal da topografia swisstopo
 - Federal Office of Topography swisstopo
 - ©swisstopo
Distribution through EMD and windPRO. 

Link to the usage-conditions (accessed 2021-10-05):

  • Usage conditions (Nutzungsbedingungen, German Language) - HERE.
  • General usage conditions (Allgemeine Nutzungsbedingungen und Betriebsbestimmungen, German Language) - HERE.

Acknowledgement

  • The SwissTopo and the Swiss public are thanked for producing this digital elevation dataset – and disseminating it in the public domain and thus for aiding the development of renewable energy.

External Links

  1. Description of the elevation model - at SwissTopo - HERE
  2. Product Sheet (pdf, german language) - HERE