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Question: Do we need to ask also for another already accumulated parameter "Percolation" [kgm-2] as some model are producing it and they would have to convert it into the rate?
Justification: The newly proposed percolation is the downward movement of water under hydrostatic pressure in the saturated zone.This water might still end up in rivers and lakes as discharge but it is a slower process than water runoff or drainage. Such defined percolation is an input for hydrological models together with e.g. water runoff. If percolation is to the ground water it can also be named as ground water recharge.
Real-life example:
The newly proposed percolation rate what be the parameter K3 in the SURFEX 3-layers scheme (right picture ISBA 3-L; it is called gravitational drainage there).
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