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For LAM grids we distinguish three main regions:
- model grid (- dynamics: whole grid, including halo/pilot region)
- physics : core grid plus 3 points - core grid (- model grid minus halo/pilot region but including blending/merging area/Davies sponge)
- free grid (- inner area)
The pilot region or halo contains only the driving interpolated to the model grid. The model need this region to check where the air comes from but the dynamics do not do any calculations in this region.
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