The modeling framework FlexSem is a fast, flexible and user friendly tool specifically targeted towards scientific and management challenges of the complex biogeochemical processes in coastal zone ecosystems. FlexSem is a modular marine modeling framework, containing a full HD module, a simplified formulation of estuarine hydrodynamics (HDLite) or it can be forced by an external hydrodynamic model. Setups can include complex descriptions of pelagic and benthic biogeochemical processes and/or sediment transport. A module for Agent Based Modelling (ABM) that can run independenly or coupled with hydrodynamics or a biogeochemical model is also available.

FlexSem allows the user to set up computational grids of different complexity ranging from simple box model configurations to high-resolution unstructured grids. It can be applied by non-experts after a short introduction and might therefore be a good candidate to support managers and scientists without the need of an extensive computing infrastructure.