The carbon cycle is based on the transfer of carbon molecules from one pool to another, where the molecules are not created, nor are they destroyed. As such, all outputs must be equal to the inputs – that is that the system is in balance. This is referred to as mass balance.
To ensure the integrity of the FLINT, mass balance is built into the FLINT’s core system. In that, all fluxes are the result of operations that draw from one pool and input into another. The FLINT can’t create a flux into a pool. For example, Flux into B = Pool A x 0.1.
While there is mass balance built into the FLINT; there is currently no set of logical stock values. For example, it will be possible for a pool to have a negative carbon stock. This will be amended in future iterations of the FLINT.