Numerical Models for Operational Ocean Observing

Abstract

Ocean general circulation models (OGCM) mathematically simulate ocean water mass movements making use of the hydrodynamic equations adhering to the conservation of mass, and energy through simplifying assumptions that allow operational algorithms. Models are built upon grids and computations are performed at grid nodes and propagated through the grid at predetermined time steps. Local coastal circulation models, addressing a smaller area, can implement denser grids providing greater detail. These however are commonly embedded or nested within large-scale OGCMs reducing computational demand by providing boundary conditions between the models. Operational assimilation of instrumental data constrains model drift, extending the fidelity of model forecasts. Lagrangian tracking of virtual particles released into or upon the water surface provides guidance for spill tracking and search and rescue operations. Spectral ocean wave models determine energy density across the wave spectrum allowing forecasts of wave heights, parameterized as significant or maximum wave height, wave period, and wave direction. Accurate coastal circulation and wave modeling requires detailed coastline and bottom topography databases as well as fine-grained model wind fields. Chemical models are being used to track and forecast ocean acidification and biological models are being tuned for prediction of harmful algal bloom occurrences.

The original version of this chapter was revised. A correction to this chapter can be found at https://doi.org/10.1007/978-3-319-78352-9_9