CliffDelineaTool v1.2.0: an algorithm for identifying coastal cliff base and top positions

Correct quantification of coastal cliff erosion requires accurate delineation of the cliff face bounded by the cliff top and base lines. Manual mapping is time consuming and relies on the mapper's decisions and skills. Existing algorithms are generally site specific and may be less suitable for areas with diverse cross-shore cliff geometries. Here we describe CliffDelineaTool (v1.2.0), a MATLAB/Python-based algorithm that identifies cliff base and top positions on complex cliffs using cross-shore transects extracted from digital elevation models. Testing on four 750-1200 m cliffed coastlines shows that the model performance is comparable to manual mapping and provides some advantages over existing methods but provides poor results for cliff sections with ambiguous cliff top edges. The results can form the basis for a range of analyses, including coastal inventories, erosion measurements, spatiotemporal erosion trends, and coastline evolution modeling.

Automated summary

This article describes an algorithm that uses digital elevation models to identify the base and top positions of complex cliffs. Testing shows that the algorithm performs comparably to manual mapping and offers some advantages, but it may not provide accurate results for cliff sections with ambiguous top edges.