Interpolation barriers

The physical, geographic barriers that exist in the landscape, like cliffs or rivers, present a particular challenge when trying to model a surface using interpolation. The values on either side of a barrier that represents a sudden interruption in the landscape are drastically different.

Elevation values change suddenly and radically near the edge of a cliff. When you interpolate a surface with this type of barrier, you can't use known values at the bottom of the cliff to accurately estimate values at the top of the cliff.

Most interpolators attempt to smooth over these differences by incorporating and averaging values on both sides of the barrier. The Inverse Distance Weighted method allows you to include barriers in the analysis. The barrier prevents the interpolator from using samples points on one side of it.

When you use a barrier with interpolation, the estimated cell value is calculated from sample points on one side of the barrier.