Geomorphometry, the science that quantitatively describes terrains, has traditionally focused on the investigation
of terrestrial landscapes. However, the dramatic increase in the availability of digital bathymetric data and the increasing
ease by which geomorphometry can be investigated using Geographic Information Systems (GIS) has prompted interest in
employing geomorphometric techniques to investigate the marine environment. Over the last decade, a suite of
geomorphometric techniques have been applied (e.g. terrain attributes, feature extraction, automated classification) to investigate the characterisation of seabed terrain from the coastal zone to the deep sea. Geomorphometric techniques are,
however, not as varied, nor as extensively applied, in marine as they are in terrestrial environments. This is at least partly due
to difficulties associated with capturing, classifying, and validating terrain characteristics underwater. There is nevertheless
much common ground between terrestrial and marine geomorphology applications and it is important that, in developing the
science and application of marine geomorphometry, we build on the lessons learned from terrestrial studies. We note, however, that not all terrestrial solutions can be adopted by marine geomorphometric studies since the dynamic, four-
dimensional nature of the marine environment causes its own issues, boosting the need for a dedicated scientific effort in
marine geomorphometry.
This contribution offers the first comprehensive review of marine geomorphometry to date. It addresses all the five main
steps of geomorphometry, from data collection to the application of terrain attributes and features. We focus on how these steps are relevant to marine geomorphometry and also highlight differences from terrestrial geomorphometry. We conclude
with recommendations and reflections on the future of marine geomorphometry.peer-reviewe
