About

Lagrangian particle tracking, is an important tool in quantifying bio-physical transports in the ocean. Particle tracking in the unstructured grids typically used in coastal regions is computationally slow, limiting the number of particles and ranges of behaviours that can be modeled.

OceanTracker was created to be 100s of times faster than an existing freely available particle tracker when using unstructured grids. More significantly, OceanTracker computational speed is simmilar to that achieved when particle tracking on a regular grid (Vennell et. al.)

This makes it possible to routinely calculate the trajectories of millions of particles. Allowing large number of particles allows much better estimates of dispersion and transport statistics, particularly when the probability of connection is low but the consequences are significant, e.g. the spread of invasive species. It also enables wider exploration of parameter sensitivity and particles’ bio-physical behaviours to provide more robust results.

The speed increases result largely from exploiting history and reuse within the spatial interpolation of the hydrodynamic model’s output. Using multiple computer cores further increased the speed to track a given number of particles.

The code can build heat maps on the fly and within polygon counts. This eliminates the need to record large data sets of particle tracks for post processing into heat maps. In addition to speed the internal architecture of OceanTracker makes it easy for the user to customise and extend.