This tool calculates the ratio between the surface area and planar area of grid cells within digital elevation models (DEMs). The tool uses the method of Jenness (2004) to estimate the surface area of a DEM grid cell based on the elevations contained within the 3 x 3 neighbourhood surrounding each cell. The surface area ratio has a lower bound of 1.0 for perfectly flat grid cells and is greater than 1.0 for other conditions. In particular, surface area ratio is a measure of neighbourhood surface shape complexity (texture) and elevation variability (local slope).

## Reference

Jenness, J. S. (2004). Calculating landscape surface area from digital elevation models. Wildlife Society Bulletin, 32(3), 829-839.

## See Also

ruggedness_index, multiscale_roughness, circular_variance_of_aspect, edge_density

## Function Signature

`def surface_area_ratio(self, dem: Raster) -> Raster: ...`

## Project Links

WbW Homepage User Manual Support WbW