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The Role of Thermohaline Fronts in Shaping the Pathways for Sediment Transport in the Vicinity of the Wave Hub. by G.I.Shapiro and D.A.Huntley. Why thermohaline fronts ?.
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The Role of Thermohaline Fronts in Shaping the Pathways for Sediment Transport in the Vicinity of the Wave Hub by G.I.Shapiro and D.A.Huntley
Why thermohaline fronts ? Thermohaline fronts are abrupt contrasts in temperature and salinity, which can generate sharp changes in water density (density fronts) Density fronts generate regional , slow varying currents
Why currents ? Currents modify the surface waves Currents transport pollution and sediment and spread the environmental impact of energy extraction over large areas of coastal waters Mesoscale circulation in the eastern Celtic Sea as seen from Landsat satellite imagery, July 1999.
Fast Tidal Streams Against Slow Regional Currents At any one time the tidal stream is the strongest current in the Celtic Sea In the longer term (over a few tidal cycles) the slow currents caused by thermohaline fronts have a much greater effect on spread of pollution and sediment Brown et al, 2003
Are Historical Observations Sufficient to Predict the Regional Currents ? Movie goes here Tidal model combined with historical observations of temperature and salinity • Fully 3D predictive model initialised with the same historical data
Development of the Temperature Front in the Summer 1 June 1998 25 June 1998 (Shapiro, Aleynik, Huntley, 2009)
Fine / Coarse Grain Sediment Transport in the vicinity of the Wave Hub Coarse sediment Fine grained sediment Arrows show direction , colour shows the relative strength of sediment transport
Advanced computer modelling NEW CAPABILITIES + Observations Building predictive capabilities in assessing the impact of wave energy generation on the marine / coastal environment in a situation which never happened before in the World’s history