A particle-tracking model for simulating pollutant dispersion in the Strait of Gibraltar.

A particle-tracking model to simulate the dispersion of contaminants in the Strait of Gibraltar has been developed. The model solves the hydrodynamic equations off-line and tidal analysis is carried out to determine tidal constants for the two main constituents. Tidal constants and residuals are stored in files that are read by the dispersion model. A lagrangian approach is used to solve dispersion; diffusion and decay are simulated by a Monte Carlo method. A method for assessing the areas of the Strait with higher probability of being affected by contamination occurring after an accident in the shipping routes is given. Generally speaking, the fate of a pollutant discharge strongly depends on wind conditions. Winds from the east tend to retain contamination into the Strait. As a consequence, transverse mixing occurs and both Spain and Morocco coasts are affected by contamination. Under calm conditions and west winds, contaminants are flushed out of the Strait faster and transverse mixing does not occur. Thus, only part of Morocco coast has a higher probability of being affected by contamination.

[1]  Michael Karcher,et al.  Modelling Siberian river runoff — implications for contaminant transport in the Arctic Ocean , 2000 .

[2]  J. R. Hunter.  The Application of Lagrangian Particle-Tracking Techniques to Modelling of Dispersion in The Sea , 1987 .

[3]  L León Vintró,et al.  Vertical and horizontal fluxes of plutonium and americium in the western Mediterranean and the Strait of Gibraltar. , 1999, The Science of the total environment.

[4]  J. Backhaus,et al.  Control Variability and Internal Bore Evolution in the Strait of Gibraltar: A 2-D Two-Layer Model Study , 2001 .

[5]  John Noye.  Numerical modelling : applications to marine systems , 1987 .

[6]  Alfredo Izquierdo,et al.  Simulation of the semidiurnal tides in the Strait of Gibraltar , 1999 .

[7]  M. Tsimplis,et al.  A two‐dimensional tidal model for the Mediterranean Sea , 1995 .

[8]  Harry L. Bryden,et al.  Estimation of the transports through the Strait of Gibraltar , 2000 .

[9]  Stephan Dick,et al.  Water transport and mixing in the North Frisian Wadden Sea — Results of numerical investigations , 1996 .

[10]  D. Pugh.  Tides, Surges and Mean Sea-Level , 1987 .

[11]  Rafael Mañanes,et al.  Non-linear interaction between tidal and subinertial barotropic flows in the Strait of Gibraltar , 1998 .

[12]  Roger Proctor,et al.  Modelling tides and surface drift in the Arabian Gulf—application to the Gulf oil spill , 1994 .

[13]  C. Winant,et al.  Tides in the Strait of Gibraltar , 1990 .

[14]  P. Mansfield,et al.  On the disposal of contaminated milk in coastal waters. , 2001, Marine Pollution Bulletin.

[15]  Roger Proctor,et al.  Forecast and hindcast simulations of the Braer oil spill , 1994 .

[16]  Paulo C. Leitão,et al.  A two-dimensional particle tracking model for pollution dispersion in A Coruna and Vigo Rias (NW Spain) , 1999 .

[17]  A. Elliott,et al.  Shear diffusion and the spread of oil in the surface layers of the North Sea , 1986 .

[18]  A. M. Riddle.  The specification of mixing in random walk models for dispersion in the sea , 1998 .

[19]  W. Schönfeld,et al.  Numerical simulation of the dispersion of artificial radionuclides in the English Channel and the North Sea , 1995 .

[20]  A. J Elliott.  Simulations of Atmospheric Dispersion Following a Spillage of Petroleum at Sea , 1999 .

[21]  A. Elliott,et al.  A particle-tracking method for simulating the dispersion of non-conservative radionuclides in coastal waters. , 2002, Journal of environmental radioactivity.

[22]  T. Jensen.  Open boundary conditions in stratified ocean models , 1998 .