In coupled models the performance of massively parallelmodel components strongly suffers from sequential coupling overhead.A coupling interface for parallel interpolation and parallelcommunication is urgently required to work out this performancedilemma. Performance measurements for a parallel coupling ofparallel regional atmosphere and ocean models are presented for theCRAY-T3E-1200 using the coupling library MpCCI. The differentrotated grids of the models MOM2 (ocean-seaice) and PARHAM(atmosphere) are configured for the arctic region. In particular, asunderlying MPI-implementations CRAY-MPI and MetaMPI are compared intheir performance for some relevant massive parallel configurations.It is demonstrated that an overhead of 10\% for coupling, includinginterpolation and communication, can be achieved. Perspectives for acommon coupling specification are given enabling the modelingcommunity to easily exchange model components as well as couplingsoftware, making model components reusable in other couplingprojects and on next generation computing architectures. Futureapplications of parallel coupling software in parallel nesting anddata assimilation are discussed
