Development of an Ocean-Atmospheric Model on Isocahedral Grids 
(Peter Korn, Max-Planck Institute for Meteorology, Hamburg).  
The Isocahedral Non-hydrostatic General Circulation Model (ICON) was developed in a joint project
with the German Weather Service.  This is the unified model for
global and regional modelling which utilises a isocahedral. The ICON
structure separates numerics from physics, exploits similarities
between atmospheric and ocean equations and imposes conservation of
discretized equivalents of global invariants.  Physical variables are
defined on a triangulated version of the grid (hexagons) and
discretized operators decomposed on a dualized (triangular) gird. 
Mass fluxes out of the dual cell are specified and shallow water
equations are integrated.  Although enstrophy conservation is a
property of the grid, the model is not energy conserving.  The model
was applied to discretized shallow water equations.  Challenges
include avoidance of interface artefacts and to overcome grid scale
limitations upon the threshold of turbulence modelling.