Investigation of wind and tidal forcing on stratified flows in Greenland fjords with TELEMAC-3D
Keywords:
Stratification, horizontal pressure gradients, Coriolis force, buoyancy force, fjord circulation, double diffusion, Ekman transportAbstract
Many researchers have analysed the effect of wind on fjord dynamics by using two-dimensional numerical models. This paper investigates the wind and tidal forcing effects on the strong stratification and circulation by application of the threedimensional model TELEMAC-3D. The capability of the model to reproduce the physical processes has been investigated by applying it to Sermilik Fjord, Greenland. This study shows that the major changes in the fjord dynamics are wind induced. Any changes in the wind speed have an instant impact on the water surface velocities. Also, the diffusively driven circulation produced by the horizontal pressure gradients at coast plays an important role in fjord dynamics. After calibration, the tidal model produced matching results with the measured wave height. The tidal analysis shows that the strength and direction of the tidal currents are sensitive to any changes in the width and shape of the domain. The effect of the tidal propagation on the salinity profile has been shown to play an important role, with salinity picks being 5–6 h behind the tidal flood and ebb picks, along the wind forcing, on the fjord circulation. TELEMAC-3D is a suitable model to simulate accurately such complicated dynamics as in presented case study.
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