SPACE OCEANOGRAPHY FOR THE MONITORING OF MOROCCAN UPWELLING DYNAMIC

摘要

The Moroccan coastal upwelling is a complex physical and biological phenomenon which requires a regular and permanent monitoring to apprehend its dynamic in time and space. In order to meet this need and considering the influence of the upwelling events on the Moroccan marine resources fluctuations, the Royal Centre for Remote Sensing (CRT) in collaboration with the National Institute for Fisheries Research (INRH), has carried out GERMA (Management of Marines Resources) project to develop useful tools and applications to generate routine operational upwelling products for supporting fisheries. The characterizing and the monitoring of the upwelling fluctuations aim at exploiting ea Surface Temperature (SST), ocean colour data and derived products combined with in situ data. The main objective is to provide users with operational products representing some environmental parameters and likely to help understanding the fish stock fluctuations. Indeed, methodologies and tools were set up to produce a derived upwelling index (CUI) from SST data. This synthetic product, based on the thermal difference between Open Ocean and coastal cold water, is particularly adapted to monitor the upwelling phenomenon along Moroccan coast and to characterize the spatial and temporal variation of the cold water ascent, taking into account the local geographical specificities. In addition, another application is developed integrating several geophysical parameters, obtained both from satellites and in situ data, which allow the analysis of this phenomenon. This application permits the time series extraction of each parameter, separated or combined with others parameters, for a selected point along the coast thus allowing easy validation of satellite-derived products and analysis of long time series. The availability of the upwelling geophysical indicators time series supplies important information for the assessment of the upwelling evolution and fluctuations.