Water balance outputs across tools
Modelling tools differ in the hydrological processes, or water balance elements, that they calculate individually, save, and allow users to export for further analyses.
| Flux or storage | Tool output and/or calculation approach | ||||||
|---|---|---|---|---|---|---|---|
| WRSM-Pitman
(Sami GW) |
SPATSIM-Pitman
(Hughes GW) |
ACRU4 | SWAT2012 | MIKE-SHE, | MIKE-SHE, | ||
| AET total | Output | no*
calculate: (long term average, not monthly due to lags): precip. - runoff – Δ soil storage – Δ GW storage |
no*
calculate: ET output (includes canopy interception) + AET from GW (external calculation) |
no*
calculate: canopy evap. + AET from soil |
no*
calculate: AET from soil + AET from GW |
YES | YES |
| Scale | (runoff module) | (subcatchment) | (HRU) | (HRU) | grid cell, polygon, catchment | grid cell, polygon, catchment
| |
| Canopy interception evaporation | Output | no# | YES | YES | not modelled | YES | YES |
| Scale | subcatchment | HRU | grid cell, polygon, catchment | grid cell, polygon, catchment
| |||
| AET from soil | Output | no# | YES | YES | YES | YES | YES |
| Scale | subcatchment | HRU | HRU, subcatchment, catchment | grid cell, polygon, catchment | grid cell, polygon, catchment
| ||
| AET from GW | Output | no# | no*
calculate: see algorithm |
not modelled
(exception: riparian HRU approximation) |
YES
(‘Revap’) |
YES | YES |
| Scale | (subcatchment) | HRU | subcatchment aquifer, catchment | grid cell, polygon, catchment, (aquifer layer or all)
| |||
| Runoff (RO) total | Output | YES | YES | YES | YES | YES | YES |
| Scale | runoff module, route (any scale) | subcatchment | HRU, subcatchment, catchment | HRU, subcatchment, catchment | river cross section | river cross section
| |
| Surface runoff | Output | no*
calculate: RO total – interflow – aquifer RO |
YES | no*
calculate: “Quickflow” – “DelayedStormflow” |
YES | YES | YES |
| Scale | runoff module | subcatchment | HRU | HRU, subcatchment, catchment | grid cell, polygon, catchment | grid cell, polygon, catchment
| |
| Interflow | Output | YES | YES
(‘soil moisture runoff’) |
YES
(‘DelayedStormflow’) |
YES
(‘Lateral Q’) |
YES | YES
(saturated zone, upper layer) |
| Scale | runoff module | subcatchment | HRU | HRU, subcatchment, catchment | subcatchment interflow reservoir | grid cell, polygon, catchment
| |
| Aquifer to channel | Output | YES | YES | YES | YES | YES | YES |
| Scale | runoff module | subcatchment | HRU, subcatchment | HRU, subcatchment, catchment | subcatchment aquifer, catchment | grid cell, polygon, catchment, (aquifer layer or all)
| |
| Aquifer GW flow in/out | Output | no | YES | not modelled | no*
GW can ‘leave’ catchment by recharging an inactive deep aquifer |
no*
GW can ‘leave’ catchment by recharging an inactive deep aquifer or ‘dead storage’ |
YES |
| Scale | subcatchment | grid cell, polygon, catchment, (aquifer layer or all)
| |||||
| Soil profile storage | Output | YES | YES | YES | YES | YES | YES |
| Scale | runoff module | subcatchment | soil layer in HRU | HRU, subcatchment, catchment | grid cell, polygon, catchment | grid cell, polygon, catchment
| |
| Aquifer storage | Output | YES | no | YES | YES | YES | YES |
| Scale | runoff module | HRU, subcatchment | HRU, subcatchment | subcatchment aquifer, catchment | grid cell, polygon, catchment, (aquifer layer or all)
| ||
| Percolation out of soil storage | Output | YES
(‘total recharge’) |
YES
(same as recharge) |
YES
(same as recharge) |
YES | YES | YES |
| Scale | runoff module | subcatchment | HRU | HRU, subcatchment | grid cell, polygon, catchment | grid cell, polygon, catchment
| |
| Aquifer recharge | Output | YES
(‘aquifer recharge’) |
YES | YES
( ‘SaturatedFlow’ B horizon + ‘UnsaturatedFlow’ if option to include is selected) |
YES | YES | YES |
| Scale | runoff module | subcatchment | HRU, subcatchment | HRU, subcatchment | subcatchment aquifer, catchment | grid cell, polygon, catchment, (aquifer layer or all) | |