From Unofficial BOINC Wiki
A Coupled Model indicates that there is a dynamic ocean rather than a "slab ocean".
A slab ocean just uses estimates for heat flow at the ocean surface. This cannot respond dynamically. In contrast a Coupled Model will have lots of cells like for the atmosphere which do respond dynamically. The model being used has 20 different layers.
Such dynamic oceans take a long time to respond to changes. Water takes about 1000 years to circulate in the Thermo Haline Circulation and this gives an indication of the timescales. Thus if the ocean is out of balance with the atmosphere provided for the model, it drifts for a long time before reaching an equilibrium. This creates the need for the 200 year long Coupled Spin-Up Models and the need for Control Models for each Transient Coupled Model.
 Also See
- Definitions of model type descriptive words
- Types of Model - Experiment list
- Climateprediction.net Model Parts
- Climateprediction Size Table