Snow Card Inputs - Optional
From Gsshawiki
The following tables list all project file cards pertaining to snow accumulation, melt, and melt-water transport. The Hybrid Energy Balance method is the default snow melt method (no additional card required to run this method).
Cards calling which snow melt algorithm to use
Melt Method | Card | Description |
---|---|---|
Hybrid Energy Balance | default (no card) |
The Hybrid Energy Balance Method for melting snow is the default, so it is utilized if NWSRFS_SNOW and EB_SNOW are not present in the Project File. |
Temperature Index | NWSRFS_SNOW |
The Temperature Index Method for melting snow is utilized if this card is present in the Project File. |
Energy Balance | EB_SNOW |
The Energy Balance Method for melting snow is utilized if this card is present in the Project File. |
Cards Associated with All Three Melt Methods
Card | Argument | Units | Description |
---|---|---|---|
NWSRFS_SCF ##.## |
real | fraction | Snow Cover Factor (adjusts for mis-readings in the gage data (see Continuous:Snowfall_Accumulation_and_Melting). |
SNOW_TEMP_BASE ##.## |
real | °C | Base Temperature (MBASE) at which melt in snow begins |
SNOW_SWE_FILE ***.swe |
File | m | Outputs time-series snow water equivalent maps (similar to DEP file). |
Cards Associated with BOTH Hybrid Energy Balance and Temperature Index Methods
Card | Argument | Units | Description |
---|---|---|---|
NWSRFS_FR_USE ##.## |
real | fraction | Specifies the fraction of precipitation in the form of rain when temperature drop below MBASE. |
NWSRFS_TIPM ##.## |
real | Snow Cover Thermal Gradient | |
NWSRFS_NMF ##.## |
real | mm/°C/dt | Negative Melt Factor. |
NWSRFS_FUA ##.## |
real | Empirical Wind Function Factor. | |
NWSRFS_PLWHC ##.## |
real | % | Percent Liquid Water Holding Capacity. |
Cards Associated with JUST Temperature Index Method
Card | Argument | Units | Description |
---|---|---|---|
NWSRFS_MF_MAX ##.## |
real | mm/°C/dt | Maximum Melt Factor, only works with NWSRFS_SNOW. |
NWSRFS_MF_MIN ##.## |
real | mm/°C/dt | Minimum Melt Factor, only works with NWSRFS_SNOW. |
Cards Associated with Vertical Melt Water Transport (Vertical MWT)
Card | Argument | Units | Description |
---|---|---|---|
SNAP_RETENTION |
Uses the SNAP model to simulate the vertical transport of melt-water through the snow pack (Vertical MWT). | ||
VERT_SNOW_RETENTION |
Uses the SNAP model to simulate the vertical transport of melt-water through the snow pack (Vertical MWT), but also distributes the melt incrementally over an hour instead of abruptly at every timestep that SNAP is run (which is hourly). |
Cards Associated with Lateral Melt Water Transport (Lateral MWT)
Card | Argument | Units | Description |
---|---|---|---|
SNOW_DARCY |
Simulates the lateral transport of melt-water through the snow pack based on work by Colbeck (1974) (Lateral MWT). | ||
SNOW_REYNOLDS ##.## |
real | Reynolds Number at which flow simulation switches from Darcian to regular Overland. Only effects cells covered by snow and only works when SNOW_DARCY card present in Project File. |
Cards Associated with Orographic Effects
Card | Argument | Units | Description |
---|---|---|---|
OROGVAR_HMET |
Adjusts the temperature in each cell based on elevation differences between the cell and the gage site (Orographic Effects). | ||
HMET_ELEV_GAGE ##.## |
real | m | Elevation (m) of the gage site where temperature is measured. Only works when OROGVAR_HMET card present in Project File. |
HMET_LAPSE_RATE ##.## |
real | °C km-1 | Dry adiabatic lapse rate of the area modeled. Only works when OROGVAR_HMET card present in Project File. |
GSSHA User's Manual
- 3 Project File
- 3.1 Required Inputs
- 3.2 Mapping Table – Optional
- 3.3 Overland Flow – Required
- 3.4 Interception – Optional
- 3.5 Rainfall Input and Options – Required
- 3.6 Infiltration – Optional
- 3.7 Channel Routing – Optional
- 3.8 Continuous Simulations – Optional
- 3.9 Saturated Groundwater Flow – Optional
- 3.10 Soil Erosion – Optional
- 3.11 Constituent Transport – Optional
- 3.12 Subsurface Drainage Network – Optional
- 3.13 Output Files – Required