r.snow given the temperature (temp) [°C], the radiation (RAD) [W/(m^2*t)], the rain (rain) [mm/t], the initial snowpack water content (in_snow) [mm] and the initial snowpack energy content (in_energy) [Kcal/m^2] calculates the snowpack water equivalent (out_snow) [mm], the snowpack energy content (out_energy) [Kcal/m^2], and the snowmelt (out_snowmelt) [mm/t] at the end of the timestep t.
This algorithm has been developed following the SHE model approach
with some modification.
For more details on the algorithms see the references.
Alternatively, the user can simply type r.snow on the command line and the program will ask for parameter values settings interactively, using the standard GRASS parser interface.
The algorithm basically estimates the needed energy to maintain the snowpack in a solid phase (in a zero snowmelt hypothesis). If the available energy is enough to melt part of the snowpack then the snow is melted and the enrgy is depleted, otherwise no melting occurs the enrgy remain available in the snowpack for further step.
Original version of program: The HydroFOSS project, 2006, IST-SUPSI. (http://istgis.ist.supsi.ch:8001/geomatica/index.php?id=1)
Massimiliano Cannata,
Istituto Scienze della Terra - Scuola Universitaria Professionale della Svizzera Italiana
Maria A. Brovelli, Politecnico di Milano - Polo regionale di Como
Contact: Massimiliano Cannata
Cannata M., 2006. A GIS embedded approach for Free & Open Source Hydrological Modelling. PhD dissertation in Geodesy and Geomatic engineering, Politecnico di Milano.
Abbott, M. et al., 1986a, An introduction to the European Hydrological System – Système Hydrologique Européen, SHE; 1. History and philosophy of a physically based distributed modeling system, Journal of Hydrology, Vol. 87, 45-59.
Abbott, M. et al., 1986b, Physically based distributed modelling of an upland catchment using the Système Hydrologique Européen, Journal of Hydrology, Vol. 87, 79-102.
Tarboton, D. G. and C. H. Luce, 1996. Utah Energy Balance Snow Accumulation and Melt Model (UEB): Computer model technical description and user's guide, Utah Water Research Laboratory and USDA Forest Service Intermountain Research Station.
Last changed: $Date$