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Abstract.-The ocean is characterized by a circulation dominated by vortex of different sizes; the vortex play a very important role in the oceanic climate as they transport energy, mass and organisms. Their study is therefore of first importance to understand the different processes that occurring in the seas at different time-space scales. The Bay of Campeche, in the southern Gulf of Mexico, is characterized by a cyclonic circulation. With the aim of identifying the origin and the formation of the cyclonic vortex, data of currents registered in an oceanographic survey and data of sea altimetry obtained with remote sensors were analyzed. From the results, the formation of the cyclonic vortex of the Bay of Campeche depends mainly on the conservation of the potential vorticity. Key words: Potential vorticity, cyclonic eddies, circulation in bays, altimetryResumen.-El océano se caracteriza por una circulación dominada por giros de diferentes tamaños; los giros juegan un papel muy importante en el clima oceánico ya que transportan energía, masa y diversos organismos. Su estudio es por tanto de primera importancia para entender los diferentes procesos que ocurren en los mares a diferentes escalas espacio -temporales. La Bahía de Campeche, en el sur del Golfo de México se caracteriza por tener una circulación de tipo ciclónica. Con la finalidad de identificar el origen y la formación del giro ciclónico se analizaron datos de corrientes registradas en una campaña oceanográfica y datos de altimetría del mar obtenidos con sensores remotos. De los resultados obtenidos se deduce que la formación de los giros ciclónicos de la Bahía de Campeche depende principalmente de la conservación de la vorticidad potencial.Palabras clave: Vorticidad potencial, giros ciclónicos, circulación en bahías, altimetría

This study examined the evolution of the beach profile and sedimentary balance in Playa del Coco, Mexico, during one year (September 2013–September 2014) to monitor these conditions at a site with little or no anthropogenic influence. The type of beach profile was determined according to the energy profile of the geomorphology, resulting in three types of profiles: low, medium, and high energy. In addition, sediment volumes were quantified, and erosion or accumulation at each study site was described. The results showed that the medium-energy profile was characteristic of the beach most of the time. High-energy conditions were recorded only once due to the influence of a high-category hurricane (Odile, III) during the hurricane season. The dominant sediment size was medium, moderately well-classified to well-classified, coinciding with the medium-energy profile. Coarse, well-sorted sand was recorded at the end of the study, coinciding with the highest loss of sediment on the beach. Playa del Coco showed a state of quasi-equilibrium before the end of the annual cycle, recovering the characteristics of the beach at the beginning of the study. After that time, there was a great loss of sedimentary material influenced by Hurricane Odile (III), modifying the beach’s state of recovery. Therefore, the stability of this beach could be cyclical and respond to the self-organization principle rather than to seasonal parameters. However, the duration of the cycles that influence Playa del Coco seems to be determined by the hurricane season, especially the combination of two main factors: the proximity to the coast of the hurricane and the amount of rainfall associated with the hurricane.