  Idealized and comprehensive ocean models at low resolutions cannot reproduce
nominally-resolved flow structures similar to those presented in the
high-resolution solution. Although there are various underlying physical
reasons for this, from the dynamical system point of view all these reasons
manifest themselves as a low-resolution trajectory avoiding the phase space
occupied by the reference solution (the high-resolution solution projected onto
the coarse grid). In order to solve this problem, a set of
hyper-parameterization methods has recently been proposed and successfully
tested on idealized ocean models. In this work, for the first time we apply one
of hyper-parameterization methods (Advection of the image point) to a
comprehensive, rather than idealized, general circulation model of the North
Atlantic.
  The results show that the hyper-parameterization method significantly
improves a non-eddy-resolving solution towards the reference eddy-resolving
solution by reproducing both the large- and small-scale features of the Gulf
Stream flow. The proposed method is much faster than even a single run of the
coarse-grid ocean model, requires no modification of the model, and is easy to
implement. Moreover, the method can take not only the reference solution as
input data but also real measurements from different sources (drifters, weather
stations, etc.), or combination of both. All this offers a great flexibility to
ocean modellers working with mathematical models and/or measurements.
