model provides daily ocean circulation on a global scale.
In the second stage the velocity data extracted from HYCOM
was coupled to a particle tracking model ‘Pol3DD’
(Black & Gay, 1990) and used to drive the dispersion of
floating material across the ocean surface. The HYCOM
model contained 32 vertical layers, but only the velocities
in the surface layer were used as the principal driver of
floating particles.
Particles were tracked on a Meridian grid between 78 °S
and 47 °N (North Pacific Gyre). The grid consists of 1500
x 1100 grid cells at ~21 km resolution and was later converted
to a 2D grid as it is illustrated in Figure 2.39. The
simulations were run at hourly time steps for a period of
30 years. The model output updated particles position
and the history of particle visits per cell on a weekly basis.