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The Chilean coastal zone (CCZ) is subjected to a complex spectrum of anthropogenic, geophysical, biogeochemical, and climate-driven perturbations. Potentially affected variables including atmospheric sea level pressure (Pa), alongshore wind, sea surface temperature (SST), chlorophyll-a, rainfall, river discharge, relative mean sea level (RMSL), and wave climate are studied using in situ and satellite records, hindcasts, and reanalysis datasets. Linear temporal trends and correlations of anomalies are estimated between 18°S and 55°S along the CCZ. The comparison of some of the variables is achieved by means of a strict homogenization procedure on a monthly basis for 35 years. Our findings show that the poleward drift and strengthening of the Southeast Pacific Subtropical Anticyclone (SPSA) partially explains the increase in Pa and reduction in rainfall and river discharge. The enhancement of alongshore winds, also attributable to changes in the SPSA, increases coastal upwelling, which in turn could reduce SST and increase chlorophyll-a. Despite differential latitudinal responses, increasing wave heights and a southward rotation are evidenced. RMSL does not show significant variation as it is presumably affected by seafloor changes during the seismic cycle. Though some correlations are evidenced, the influence of climate variability at decadal scale (PDO, SAM) may be affecting the detected trends due to the short length of available data. Impacts on coastal communities, infrastructure, and ecosystems are discussed, aiming to highlight that coastal vulnerabilities and risk management should be based on the cumulative impacts of these variables.

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RESUMEN.El temporal del 8 de Agosto de 2015 se caracterizó por la ocurrencia conjunta de condiciones meteo-oceanográficas que causaron la destrucción de infraestructura costera y edificaciones en varias localidades del litoral central de Chile. El oleaje extremo se sumó a rachas de vientos provenientes del noroeste y una mínima histórica de la presión atmosférica asociada al sistema frontal. La marea de origen astronómico -aun cuando no extrema-hizo su contribución para peraltar el nivel del mar sobre el cual las olas rompieron con violencia en el borde costero. Para estudiar el evento se procesaron: a) registros de 64 estaciones meteorológicas distribuidas en el sector costero de las regiones de Valparaíso y Coquimbo, b) registros de 6 estaciones mareográficas en Chile Central, c) pronósticos y registro de oleaje en aguas profundas, y d) un modelo de propagación de oleaje desde aguas profundas hacia los sectores más afectados de la región. A partir del análisis de estas variables se explican los daños observados en la infraestructura costera. Palabras clave: registros de viento, oleaje, presión atmosférica, marea astronómica. The storm of August 8, 2015 in the regions of Valparaíso and Coquimbo, Central ChileABSTRACT. A storm of August 8, 2015 was characterized by the joint occurrence of meteorological and oceanographic conditions that caused the destruction of coastal infrastructure and buildings in several localities of the central coast of Chile. The extreme swell was added to wind gusts coming from the northwest winds, and a historical minimum of atmospheric pressure. The tide of astronomical origin -although not extreme-, made its contribution to the sea level banking on which the waves broke violent on the coastal edge. In order to study the event, records of: a) 64 weather stations distributed in the coastal zone of Valparaiso and Coquimbo regions, b) six tide gauge stations, c) forecast and wave records in deep-waters, and d) a model of deep-water wave propagation towards the most affected sectors of the region, were processed. From the analysis of these variables, the observed damages in the coastal infrastructure are explained.