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The global gradient-based groundwater model framework G³M-f is an extesible model framework.
Its main purpose is to be used as a main building block for the global groundwater mode G³M.
G³M is a newly developed gradient-based groundwater model which adapts MODFLOW (https://water.usgs.gov/ogw/modflow/MODFLOW.html) principles for the global scale.
It is written in C++ and intended to be coupled to the global hydrology model WaterGAP (http://watergap.de), but can also be used for regional groundwater models and coupling to other hydrology models.
While it is intended to be used as a in memory coupled model it is also capable of running a standard standalone groundwater model.