Model help:TopoFlow-Snowmelt-Degree-Day
TopoFlow-Snowmelt-Degree-Day
This module is the snowmelt process component (Degree-Day method) for a D8-based, spatial hydrologic model
Model introduction
This process component is part of a spatially-distributed hydrologic model called TopoFlow, but it can now be used as a stand-alone model.
Model parameters
Uses ports
• Meteorology (for air temperature, T_air, etc.)
Provides ports
• Snow (snowmelt)
• Configure (tabbed dialog GUI to change settings)
• Run (only if used as the Driver)
Main equations
- Meltrate, mm/sec
[math]\displaystyle{ M= \left ( c_{0} / 86400 \right) \ast \left ( T_{air} - T_{0} \right) }[/math] (1)
- Max possible meltrate, mm/sec
[math]\displaystyle{ M_{max}= \left ( 1000 \ast h_{snow} / dt \right) \ast \left ( \rho_{water} / \rho_{snow} \right) }[/math] (2)
- Change in snow depth, meters
[math]\displaystyle{ dh_{snow}= M \ast \left (\rho_{water} / \rho_{snow}\right) dt }[/math] (3)
Symbol | Description | Unit |
---|---|---|
c_{0} | coefficient | - |
T_{0} | threshold temperature | deg C |
T_{air} | air temperature | deg C |
ρ_{snow} | density of the snow | kg / m^3 |
ρ_{water} | density of liquid water, 1000 | kg / m^3 |
h0_{snow} | initial snow depth | m |
h_{snow} | snow depth | m |
h0_{swe} | initial depth, snow water equivalent | m |
h_{swe} | depth, snow water equivalent | m |
M | meltrate | mm / sec |
M_{max} | max possible meltrate | mm / sec |
d_{h} | change in snow depth | m |
Notes
For each variable, you may choose from the droplist of data types. For the "Scalar" data type, enter a numeric value with the units indicated in the dialog. For the other data types, enter a filename. Values in files must also have the indicated units.
Single grids and grid sequences are assumed to be stored as RTG and RTS files, respectively. Time series are assumed to be stored as text files, with one value per line. For a time series or grid sequence, the time between values must coincide with the timestep provided.
All variables and their units can be seen by expanding the Nomenclature section above.
Examples
An example run with input parameters, BLD files, as well as a figure / movie of the output
Follow the next steps to include images / movies of simulations:
- Upload file: https://csdms.colorado.edu/wiki/Special:Upload
- Create link to the file on your page: [[Image:<file name>]].
See also: Help:Images or Help:Movies
Developer(s)
References
Zhang, Z., D.L. Kane and L.D. Hinzman (2000) Development and application of a spatially-distributed Arctic hydrological and thermal process model (ARHYTHM), Hydrological Processes, 14, 1017-1044.
Links
Related Help Pages
Model Metadata