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| Volet |
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SFCVAR(name_sfc, name_bus) |
Where:
'name_sfc' is the name the field will have in the surface bus and
'name_bus' is the "VN" name the one of the busses above.
The main specialty with this bus is that it is "different" for each surface fraction. It always contains all surface fields but only for the points for which a certain surface scheme is valid. For example, when a land surface scheme (ISBA, SVS, CLASS) is called, this bus will only contain points with a land fraction greater than a certain threshold. By doing this one avoids nasty if-constructions inside the surface routines checking that a point has a valid surface fraction and the bus is more compact, without any "holes".
Explain what a bus is: slab with just land points etc.
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