Balouin, Y., Belon, R., 2014. Evolution of Corsican pocket beaches. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 096–101, ISSN 0749-0208.
Pocket beaches are small beaches that are formed between headlands and within coves along rocky shorelines. They can be composed of a mix of boulders, pebbles, sand and mud and therefore have the attributes of a combination of shoreline types. Their evolution depends on wave forcing and morphological characteristics, and the most commonly observed dynamic is that of beach rotation due to prevailing wave direction. In this study, 44 pocket beaches off Corsica Island, in the Mediterranean were studied. The absence of significant tides and the generally weak coastal currents restrict significant beach morphology changes to the most important storm events though the variability of coastal evolution suggests that other factors played a role. To assess these evolution parameters, the morphological characteristics of the beaches as well as the historical evolution of the shoreline were studied. This analysis, based on aerial photos and DGPS surveys, allowed for the behavior of beaches over historical (1948–2012) period to be assessed. Over this period, 15 beaches are considered to be in erosion, 16 are stable and the others show shoreline progression. The historic analysis, through several increments of time, shows that beaches have been in perpetual movement. Moreover, some periods are particularly erosive (i.e., 1996 to 2002) for a number of beaches. Several parameters must be considered to explain the beach behavior changes such as: beach orientation, closure, geology, hydro-climatic regime, grain size and length. The wave backward modeling ANEMOC was used to analyze wave characteristics and the occurrence and direction of the most important storm events. The entire dataset was used to obtain a conceptual model describing the most important factors involved in the contrasting coastal evolutions observed, i.e., symmetric or asymmetric beach rotation, homogeneous retreat or progradation and rapid shoreline movements due to the presence of beach-cast Posidonia Oceanica seagrass litter.
