A new boundary small eddy additions technique improves long-term integration results of one-way nested regional ocean model

Generation of small-scale structure in dynamical downscaling and nesting procedure using the regional oceanographic models is really an important issue. A great number of studies have shown that small-scale features in one-way nested regional circulation model are well generated when driving by large-scale flows and information supplied from global-scale model output or observations at the lateral boundaires and incorporates with local forcing. This research, however, find that reproduction of small – scale motions is too weak enven sustain the energy at larger scales, then leading to degradation of results of nested regional ocean model. Base on that, this work proposed an efficient method, named “boundary small eddy additions” to improve the quality of nested regional ocean model’s results even though a stimulating source absents in the domain of simulation. In this technique, new adding artificial small-scales motions, which are constructed from the information of large-scale, are added at the boundaries in a nested model. This method can significanty enhance the reproducing of the model and help to reduce the horizontal resolution jump different between driving data and nested model.