Application of MOHID-water modelling system to the Nervion estuary (North Spain)

Supervisors: Angel Borja, Marina Chifflet (AZTI)
This study allows an understanding of the local hydrodynamic and hydrology of the Nervion estuary (North Spain) using MOHID-water modelling system and provides prediction of the oceanographic variables which tightly influence the important species of the system. This contribution will give advantage to the European Research Project MARS (Managing Aquatic Ecosystems and water Resources under Multiple Stress) in an objective of understanding the effects of multiple stressors on surface waters and ground waters, their biota, and the services they provide to humans. The result of numerical simulations, obtained using the MOHID-water modelling system, for the dynamic and hydrological variables of the Nervion estuary were compared to the observations. Hydrodynamic modelling was carried out to predict the hydrological characteristic for a specific period in which data were available. Numerical tests were constructed to find the best configuration for the hydrodynamic in order to produce some hydrological characteristics of the Nervion estuary, by imposing three main forcing: tide, wind and river discharge. The results showed that the model feet well the observations for the tides. The model was able to reproduce a coherent salinity plume. The time lag of the salinity in response to the discharge was also characterized. This let us know about the time the freshwater takes to disperse in any point of the estuary after a high river discharge event. This information could be a background knowledge related to the dispersion of contaminants from the river.