How to use orography from DataForWind in WAsP using Surfer:
- Extract the DEM in GRD format
- In Surfer, create a Contour map following this process:
- The Map | Contour Map | New Contour Map command creates a height contour map from a GRD file. A contour map is a two-dimensional representation of three-dimensional data. The first two dimensions are the XY-coordinates, and the third dimension (Z) is represented by lines of equal elevation. The relative spacing of the contour lines indicates the relative slope of the terrain surface. The area between two contour lines contains only grid nodes having Z values within the limits defined by the two enclosing contours. The difference between two contour line values is defined as the contour interval.
- To create a new contour map:
1. Click Map | Contour Map | New Contour Map.
2. Select a grid file in the Open Grid dialog.
3. The map is created and shown.
- To change the features of the contour map, open the contour map properties dialog by either one of the following:
- double-clicking on the map in the plot window,
- double-clicking on the map name in the Object Manager,
- right-clicking the map and choosing Properties in the context menu,
- or by clicking Edit | Properties when the contour map is selected.
- Click on the Levels tab to edit the contour lines. Delete all the contours with a value inferior to 0. Single contours can be Added or Deleted by clicking the respective buttons. Click the Level heading to change the contour interval. Click Ok to see the final map displayed.
- Finally, click Map | Contour Map | Export Contours to save map as AutoCAD DXF file or File | Export to save map as Atlas Boundary (BNA) file. Both formats can be read by the WAsP Map Editor and subsequently saved as a WAsP MAP file. This file can be inserted in the WAsP hierarchy.