Usually a combination of both, yet in some areas one can be more dominant. Flow is not prescribed through the Bering Strait or the channel. The spinup forcing consists of 365 files, each representing one day of forcing data, and each day represents a 15 year average for that day. We have not as yet performed any integration using forcing from any actual years. At the beginning of the 10th year of spinup, deep acceleration for diffusion was turned on.
Deep acceleration is a numerical technique that helps bring a model toward equilibrium faster.
Below 3050 m, the deep ocean evolves ten times faster than the upper ocean. Each year of model integration results in a decade of deep ocean integration. Deep acceleration for diffusion was turned off at the end of spinup year 20. In essence, the deep ocean has been integrated for 110 years at this point. This is being performed to eliminate or smooth any potential discontinuities that may have resulted from the deep acceleration for diffusion technique.