Percorrer por autor "Cooper, J. A. G."
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- Storm impacts on a coupled human-natural coastal system: resilience of developed coastsPublication . Malvarez, G.; Ferreira, Oscar; Navas, F.; Cooper, J. A. G.; Gracia-Prieto, F. J.; Talavera, L.Human occupation of and alteration of the world's coast has transformed large stretches of it into Coupled Human-Natural Systems (CHANS) in which humans both influence and are influenced by coastal evolution. In such systems, human activity is as critical on natural resilience as processes and sediment supply derived from the natural setting. Pre- and post-storm observations of these interactions on the intensively developed Atlantic coast of the Gulf of Cadiz, (Spain and Portugal) are examined to determine natural and engineering resilience. Three case studies are used in three CHANS, showing that human interventions interact in complex ways with the natural system influencing post-storm recovery. In natural coasts, storm impact is assessed in terms of geomorphological response; on developed coasts, it is quantified as damage to infrastructure or loss of amenity. Preparedness, availability of resources, choice of response and the speed at which human agencies respond affect resilience for post-storm beach behaviour. Results show in some sites natural resilience adjusting by post-storm sediment transfers and an equilibrium morphology that may differ from pre-storm morphology; engineering resilience ensured that CHANS regained their pre-storm human infrastructure and amenity. Their management requires a fundamentally different approach to that of natural coastlines. The current immature stage of understanding of CHANS (especially the human preparedness and response components) is illustrated by the case studies presented where short-term political decisions and reactions to storms play a strong role in post-storm response. The nature and extent of many developed coasts as CHANS is slowly becoming more widely acknowledged, but to increase natural resilience and decrease vulnerability in CHANS better planning is required so that future storms are anticipated and when they happen, pre-planned human response actions are activated. Storms are an integral and inevitable element in the behaviour of coastal CHANS, not a disaster or emergency. (C) 2021 Published by Elsevier B.V.
- Stratigraphy, evolution and morphology of a sand-rich shorefacePublication . Green, A. N.; Cooper, J. A. G.; Draycott, H. L.; Loureiro, CarlosShoreface morphology and stratigraphic evolution are poorly documented along most of the world’s coasts yet are acknowledged to be important influences on shoreline behaviour during changing sea levels. A wide, low gradient, wave-dominated shoreface characterises the area off Xai-Xai in southern Mozambique. It is developed on a Holocene wave ravinement surface cut into deltaic sands punctuated by lithified aeolianite ridges. The 2 kmwide mobile shoreface sand body extends to − 23 m depth and averages 10 m in thickness. The modern shoreface bathymetry mimics the underlying wave ravinement surface and this, in turn, is influenced by the presence of aeolianite ridges that create a pronounced break in slope that defines the base of the modern shoreface. The aeolianite influences the wave ravinement profile from which the modern bathymetry is inherited. Comparison with theoretical equilibrium shoreface profile models reveals contrasting shoreface morphodynamic state conditions, dependent upon the model chosen. Based on the model better suited for the lower shoreface. These results emphasize the widely acknowledged but still poorly understood role of geologic inheritance on shoreface morphodynamics and geomorphological evolution, even in sand-rich environments.
