still in developing,
MPAS is global model, and it solves the problem of boundary issue with regional model. It also can work with high resolution.
Please reference the following manuscript when introducing MPAS-O: T. Ringler, M. Petersen, R.L. Higdon, D.W. Jacobsen, P.W. Jones and M. Maltrud, 2011, A Multiresolution Approach to Global Ocean Modeling , Ocean Modeling, accepted, 10.1016/j.ocemod.2013.04.010, (PDF)