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Pilkey, O.H. and Cooper, J.A.G. 2014. Are natural beaches facing extinction? 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. 431–436. ISSN 0749-0208. On a generational scale, on developed shorelines, the world's recreational beaches are doomed. This is largely because of the widespread assumption that preservation of buildings is a higher priority than preservation of beaches in response to sea level rise. Continuing beach degradation will be inevitable through active or passive processes. Active degradation means the actual removal of the beach, mostly as a result of shoreline engineering or mining. By far, the most important cause of beach loss in this category will be hard structures, especially seawalls. The incorrectly but widely perceived panacea of each replenishment will become economically impossible because of raised sea levels. Replenishment leads to intensified bea...

Loureiro, C., Ferreira, O., Cooper, J.A.G., 2014. Non-uniformity of storm impacts on three high-energy embayed 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. 326–331, ISSN 0749-0208. Coastal storms are highly significant and destructive events and important natural hazards that have major impacts upon the physical and human-cultural coastline environments. Exceptional coastal storms in the last decades have emphasized the urgent need to reinforce scientific knowledge regarding the frequency, impact and role of these extreme events. This is particularly relevant for embayed beaches, where geomorphological control promotes characteristic morphodynamic responses that are distinct from the better studied long-linear beaches. This paper analyses storm response from datasets of morphological change obtained from three embayments located in three distinct wave environments...

In spite of the worldwide abundance of beachrocks and their acknowledged utility as an indicator of former sea level position, some studies have expressed doubt as to their position of cementation on paleo shorelines. These criticisms are not, however, coupled with nuanced sedimentological studies of beachrocks. Instead, few beachrock studies acknowledge any facies and therefore disregard important signatures of the depositional environment and, consequently, utility as paleo sea level indicators. This study presents detailed sedimentological descriptions and interpretations from two beachrock localities along the subtropical, microtidal, wave-dominated eastern coastline near Durban, South Africa. The outcrops record the migration of a paleo inlet and deposition in sub, inter, and supra tidal environments. Understanding the inferred depositional environment, and observed stratigraphic relationships between various beachrock facies is critical to teasing out the local evolution of shoreline and relative sea level. The outcrops studied here record multiple episodes of Holocene sea level rise and fall.

Green, A.; Cooper, J.A.G., and LeVieux, A., 2013. Unusual barrier/inlet behaviour associated with active coastal progradation and river-dominated estuaries. The mesoscale behaviour of unusual barrier inlets on the east coast of South Africa is described. The inlets are associated with river-dominated estuaries and are consequently subject to periodic closure during low river flow. They are also located on a prograding barrier coast. Deflection of the estuary channel of a small river in the direction of longshore transport by 1230 m resulted in its capture by the estuarine channel of a larger river. The larger catchment river was not deflected by coastal progradation but maintained its position by periodic breaching of a channel through the barrier during floods. Flood breaches reseal by landward reworking of ephemeral deltas and may undergo limited migration. A tidal inlet at the northern end of the barrier is maintained by a small tidal prism and has a flood-tidal delta. It exhibits limited late...

There are more than 15,000 barrier islands in fetch-limited nearshore environments around the world. About half that number are actively evolving (eroding, accreting, migrating) in response to oceanographic processes and are the subject of this study. The remaining half consists of inactive islands protected by surrounding salt marsh or mangroves. Despite their global abundance these islands have not been previously systematically studied or even recognized as a major landform type. More than 70% of fetch-limited barrier islands are found on trailing edge coasts because conditions there are favorable for formation of sheltered waters. Fully 50% are found in the coastal zone of Australia, Mexico, and Russia. We identify eight different types of fetch-limited barrier islands based on genesis and mode of occurrence. Most of the active islands form in estuaries or bays (Spencer Gulf Australia), behind open ocean barrier islands (Pamlico Sound, North Carolina), or on flood tidal deltas of open ocean t...

Despite acknowledgement by scientists and modelers of the shortcomings of mathematical models of beach behaviour, they continue in widespread use for engineering design and environmental impact studies. In part, this is because of the assumed absence of a viable alternative approach to prediction. The objective of this paper is to suggest that a conceptual approach can succeed as an alternative to mathematical models for predictions with accuracy ranges useful for engineering and coastal management purposes. The most valuable information for prediction is past engineering experience on the beach in question or the experience on neighboring beaches. The next most useful may be the global experience on oceanographically similar beaches. Another approach is the use of geoindicators and field studies on the beach. The widely applied “predict nothing” approach to beach engineering may well work if fortified by common sense. Finally, a composite approach in which the assembled body of information on a ...

Two barrier island systems from southern Mozambique (Inhaca and Bazaruto) are described. Both systems comprise a composite barrier island or barrier island chain that developed on a steep continental margin as a result of initial (Pleistocene) spit progradation. Continuing aeolian dune deposition against this initial core during subsequent sea-level highstands and lowstands has given rise to the highest dunes (120m) of any known barrier island. Wave reworking of the composite barrier island sediment during the past 6000 years of the Holocene sea-level highstand has resulted in the formation of spits, barriers, barrier islands and bluffs on the downdrift and bay side sections of the barrier island systems. The relative stability in position of the barrier systems at contemporary sea level is attributed to their large sediment volume and the development of equilibrium shoreline forms under swell waves. Beachrock and aeolianite outcrops provide anchor points for the development of contemporary shore...

The role of statutory designations to regulate activities is an important element in coastal zone management in Europe. In this paper we assess the utility of one such designation the “Area of Outstanding Natural Beauty” as a tool for coastal management in Northern Ireland. The designation is based on landscape quality and offers the potential for an integrated approach. However a variety of weaknesses reduce their effectiveness. Several suggestions are offered to improve the utility of this designation.

The methods used to determine or predict volumes of sand transported by longshore currents are briefly reviewed. We argue that the methods are flawed and that a fundamental re-examination of both field and theoretical approaches is in order. Net transport numbers obtained by any existing method should be considered order-of-magnitude values at best that are in no case sufficiently precise for coastal engineering purposes such as prediction of beach nourishment costs and environmental impacts.

Methodological aspects of GPS (Global Positioning System) and Total Station (Electronic Distance Measurement) surveying techniques were examined as part of a beach monitoring programme which was used to assess morphological variation of a high-energy beach system at Runkerry, Co.Antrim, Northern Ireland. The accuracy of the instruments as well as data processing methods concerning data conversion in different plane coordinates systems is discussed. GPS with Real Time Kinematics (RTK) provides high-resolution control on topographical surveying within limits on the order of centimeter-level accuracy in the horizontal and 2 cm in vertical dimension. Total station (EDM) also demonstrated high accuracy during its use in the monitoring programme. The model of EDM used in this work had a 5 to 6 degrees offset angle for the orientation due to the inherent characteristics of the instrument. A threshold-narrowed point selecting treatment was used to form a beach profile point set for the profile plot and any further processing. This work demonstrates that a two-dimensional translation and rotation for horizontal dimension data conversion is preferable over linear regression method; while the linear regression method for the vertical dimension data is still acceptable. It is suggested therefore that when a conversion of beach surveying data from one plane coordinate system to another is required, then this combined approach should be adopted in the analysis.