How is sulfuric acid handled?

This schematic shows how sulfuric acid is handled in different modelling scenarios. The reason for this seemingly complex logic is that sulfuric acid is very special compound that takes part in many parts of atmospheric phenomena, and the model tries to handle situations where input is used instead of modelling, or if the chemistry for some unimaginable reason has not included sulfuric acid (you probably should not use such scheme). In case you are interested what different option combinations mean in perspective of sulfuric acid, here goes. Note that in the figure the meaning of the crossed over H2SO4 is that H2SO4 is not included in the list of Variables, or that "Ignore input H2SO4 and always..." option is checked.