|WORLD METEOROLOGICAL ORGANIZATION||
|Explanation of the criteria for classification and numbering of components||
|Explanation of the dates on the component's description|
SACRAMENTO SOIL MOISTURE ACCOUNTING MODEL (NWSRFS-SAC-SMA)
1. Purpose and objectives
The Sacramento Model is a conceptual soil moisture accounting model. It is an attempt to parameterise soil moisture characteristics in a manner
that logically distributes applied moisture in various depths and energy
states in the soil and that has rational percolation characteristics.
The model represents the distribution of soil moisture by an upper and lower zone. Within each zone the moisture is separated into tension water
(water held tightly by soil particles) and free water (water which can move within the soil mantle). The movement of water between the two zones is
Required are times series data for precipitation (rain plus melt); optional are times series of evapotranspiration and areal extent of snow
cover. User supplies values of the model parameters. The model requires proper definition of the input data to produce satisfactory results.
Times series of channel inflow (runoff), runoff components and soil moisture storages are output.
5. Operational requirements and restrictions
a) One person with knowledge and experience in hydrological processes,
b) With the qualification described above, training and experience are
c) Program is written in FORTRAN. The program runs as part of the
d) Maximum array sizes are variably dimensioned and are specified by
6. Form of presentation
Source code and written documentation. The main execution routine and documentation
are available from the HOMS National Reference Centre (HNRC) of USA. These files can be obtained through ftp procedures.
7. Operational experience
The model has been used in humid, arid and semi-arid areas with good results; usage in USA by National Weather Service; implementation is complex.
8. Technical support
Dr Michael Smith, Hydrologic Research Laboratory, NOAA-NWS.
10. Conditions on use
| Reclassified from J05.3.02 MAR 1987
(First entered: 03 FEB 81
Last updated: 09 NOV 99)