The Modelling of Coastal Cliffs and Future Trends

Abstract

About 80% of the world's oceanic shorelines include diverse types of cliffed and rocky coasts: plunging cliffs, bluffs backing beaches and rocky shore platforms. In combination, approximately 60% of the world's population lives within 60 km of the coast. Rapidly retreating soft cliffs may be found worldwide and are particularly vulnerable to changes in the forcing factors. The study and analysis of the rate of change in shoreline position through time is important or even imperative for coastal management. The development of cliff erosion predictive models is mainly limited to geomorphological data because of the complex interactions between physical-chemical processes acting simultaneously in time and space that result in large scale variations. Current historical extrapolation models use historical recession data, but different environments with the same historical values can produce identical annual retreat characteristics despite the potential responses to a changing environment being unequal. For that reason, process-response models (PRMs) are necessary to provide quantitative predictions of the effects of natural and human-induced changes that cannot be predicted using other models. Several models are explained and discussed, including a process-response model, based on real data at Holderness Coast (UK).

Tracking the behavior of rocky coastal cliffs in northwestern Spain

“…These types of cliff are cascading systems whereby weathering and oversteepening by waves deliver debris from the cliff face to the cliff foot. This material accumulates, at its angle of repose, until undercut and steepened by wave action, in single or multiple storm events, destabilizing the deposit and promoting its removal by landslides and wave action (McLean and Davidson 1968;Castedo et al 2017;Trenhaile 2020). In some areas, debris removal may also be facilitated by increasing exposure to wave action as the toe of a growing talus migrates seawards.…”

Submarine Geomorphology of the Southwestern Sardinian Continental Shelf (Mediterranean Sea): Insights into the Last Glacial Maximum Sea-Level Changes and Related Environments

“…The interpretation of the kinematics of these drowned-landslides was based on the geomorphological surveys of similar palaeo-landslides located along the coast (between Capo Altano and Porto Paglia. In this sector, large landslides with rotational kinematics were systematically observed [68]. The first landslide is located 500 m north of Altano Cape, while the second landslide has been recently found to the south of Porto Paglia ( Figure 10A).…”

Cliff erosion – mapping, causes and effects in the coastal zone near Cape Kaliakra (northern Bulgarian Black Sea)

“…The average height of the erosional cliff is 50 m and the relative quantity of eroded material is 0.5 m 3 per year (Shuiskij and Simeonova, 1982). The factors forming the erosional cliff type in this region are denudation (weathering, erosion) and to a lesser extent wave activity (Shuiskij and Simeonova, 1982;Castedo et al, 2017). Under the effect of the non-wave factors, the weakly cohesive aragonite sediments of the Topola Formation reach a steep, almost vertical profile.…”