| Variable or Parameter | Units | Examples |
| unit area | m2 | All SOM and biomass pools. |
| simulation pool | g m-2 * simulation layer thickness (cm) | SOMTC output variable |
| leached pool | g m-2 | STREAM(2) output variable |
| density | g cm-3 | BULKD site parameter |
| thickness | cm | THICK site parameter |
| erosion amount | kg m-2 month-1 | EROD event |
| soil water amount | cm of H2O within a layer or range | ASMOS output variable |
| volumetric soil content | cm of H2O per cm-3 soil | used internally |
| precipitation | cm of H2O per month | PRECIP site parameter |
| temperature | degrees Celcius | STEMP output variable |