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This article discusses a case study made on research carried out on a currently decaying inner harbor in a Cantabrian estuary (ría) (northern Spain), of which natural shelter conditions had led to the development of an old fishing vessel refuge against extraordinary winds and storms and the subsequent construction of a port. Previous research work has been on-going since 1978, seeking shore protection through simple beach restoration based solely on field observations with purely morphodynamic comprehension aims. The object of this investigation work is to now analyze possible definitive solutions for stabilizing the port's entry channel and maintaining its depth by using not only accumulated field experience but new measurements and numerical models. [ABSTRACT FROM AUTHOR]

The article describes El Niño and other concomitant phenomena happening around the globe. El Niño is a change in the movement of surface waters on the Peruvian platform, which ceases to sweep the waters to the open sea and, instead, causes them to flow toward the coast. The phenomenon is perfectly explained by the Eckmann model, which explains the drift current or movement of surface waters under the action of prevailing winds. Atmospheric circulation is well known and is the response of the "heat engine," formed by the oceans and the atmosphere, to the unequal heating of the Earth's surface by solar radiation. The author is concerned by the frivolous or anticipatory manner in which changes in weather have been handled and by the fact that the greenhouse effect has been attributed to the increase in carbon dioxide.

This paper discusses the following items affecting the comprehensionand evaluation of the 'sea-level rise' phenomenon and an accurate determination of real present values and trends: (1) the question of the carbon dioxide increasing production rate related to its predictable atmospheric accumulation rate; (2) the question of the incidence ofthis further rate in the 'greenhouse effect'; (3) the question of suitably discerning its real singular impact in the present climatic change and, consequently, of accurately predicting future trends, and (4) the question of relating the 'sea-level rise' trend to short and long term trends of the 'climate change'. It discusses the subsidence factor in sea-level changes and its time-spatial variability and the different phenomena usually included in it, as a major element of confusion; the general and local factors and the different conditions between the Mediterranean and North-Atlantic (East-North America and Northwest Continental-European, where most of the surveys have been developed and issued) coasts. The paper also considers different impactsattributed to sea-level rise on coastal and shoreline evolution, critically analyzing some conclusions on coastal engineering and management. [ABSTRACT FROM AUTHOR]

The rias are a characteristic feature of the Spanish coasts. Despitetheir important differences, all of them have some common problems such as those derived from infilling processes. Their littoral dynamics have been considered, with special attention to the Cantabrian coast, and a phenomenon particularly frequent in all indentated coasts has been observed: the reversion of the general direction of processes within the indented area; this phenomenon is essential to understanding the mechanisms of formation and evolution of the inlet shoals and emerged barriers of the rias, which separate their internal (sheltered) and external (open) zones; many different morphological observations have verifyed it (Diez, 1996 b). Current morphodynamics has been accurately approached in the ria de Foz (Diez, 1980-96) to get a morphodynamic model suiting the natural as well as the anthropic evolution. The balance of sediments used to verify the model (Escobar et al., 1991) is justified and summarized. Data about deposit volumes at different times had to be laboriously obtained to show total consistence with the morphodynamic model insider. [ABSTRACT FROM AUTHOR]