How to choose which model to use

OpenDrift contains a few specific models for several applications such as oil drift, search and rescue and fish eggs.

The table below shows an overview of the advection processes within the main models:

Model

Move with currents

Direct wind drift

Stokes drift

Vertical motion

OceanDrift

yes

yes (optional wind_drift_factor)

yes

advection, turbulence

OpenOil

yes

yes (optional wind_drift_factor)

yes

wave entrainment, turbulence, buoyancy, advection

Leeway

yes

yes, at an angle. category-based empirical empirical wind_drift_factor

implicit in wind

no

PelagicEgg

yes

no

yes

turbulence, buoyancy, advection

PlastDrift

yes

no

yes

empirical-statistical depth, exponential decrease with depth, depending on turbulence/wind

OpenBergOld

yes

yes

implicit in wind

no

Direct wind drift is only applied to elements/particles at the very surface. Elements may be seeded with a user defined property wind_drift_factor (default is typically 0.02, i.e. 2%) which determines the fraction of wind speed at which elements will be advected.

Surface Stokes Drift must be obtained from a wave model, whereas the depth dependency is parameterised according to Breivik et al. (2014).

Vertical entrainment, mixing and refloating is largely following Röhrs et al. (2018)

All models are subclasses of OpenDrift, or OceanDrift and inherits all core functionality from there. The OpenDrift class itself has no specification of advection or other processes, and can thus not be used directly.