|WORLD METEOROLOGICAL ORGANIZATION||
|Explanation of the criteria for classification and numbering of components||
|Explanation of the dates on the component's description|
SNOW ACCUMULATION AND ABLATION MODEL (NWSRFS-SNOW-17)
1. Purpose and objectives
The National Weather Service River Forecast System (NWSRFS) snow accumulation and ablation model is a conceptual model of the physical processes affecting snow accumulation and snowmelt using air temperature
as the sole index of energy exchange at the snow-air interface.
The model separates snowmelt during rain-on-snow periods from melt during non-rain periods to account for differences in the magnitudes of the
energy transfer processes. During rain-on-snow periods melt is computed by
an energy balance equation after making several simplifying assumptions.
Aside from user specified parameters and program options, time series of precipitation and temperature are needed. Time series of observed water equivalents and areal snow cover can also be used. Input format is disk file.
Printer output. Rain plus melt time series data are produced, as are simulated water-equivalent and areal snow cover values. Time series are written to a file.
5. Operation requirements and restrictions
a) One person with knowledge and experience in hydrological processes,
6. Form of presentation
The main execution routine and documentation is available from the
HNRC of USA. These files can be obtained through ftp procedures.
7. Operational experience
Has been applied to a wide range of snow cover and climatic conditions
throughout the USA with good results; regular usage in U.S. by National Weather Service; implementation is complex.
8. Technical support
Dr. Victor Koren, Hydrologic Research Laboratory, NOAA-NWS.
From the HOMS National Reference Centre for USA.
10. Conditions on use
| Reclassified from J40.3.01 MAR 1987
(First entered: 03 FEB 81
Last updated: NOV 99)