Create Roughness Grid From Landcover Layer...

This option allows you to generate a grid (and optionally areas) of roughness length values from a land cover layer. When you select this option, the following dialog appears allowing you to setup the roughness calculation:


The roughness grid is useful for wind power applications and can be exported to a WindSim GWS file as a roughness layer or the  roughness areas can be exported to a WaSP .map file.

Several land cover data sets useful for roughness length calculation, like CORINE, NLCD, and VCF, have built-in roughness conversion tables available.

Custom roughness tables can be defined in a roughness_tables.txt file in the user data file path listed on the Configuration > General > Advanced dialog. A sample roughness_tables.txt file can be found here.

Specify Bounds...