User:Jcreer/SMS:GSSHA Model Control

General

• Total time (TOT_TIME) – Enter an integer giving the total duration of the simulation in minutes
• Time step (TIMESTEP) – Enter an integer giving the duration of each time step in the simulation in seconds. The time step must be evenly divisible into 60 seconds (e.g., 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, or 60 seconds).
• Outlet slope (OUTSLOPE) – Enter an integer for the slope of the cell containing the watershed outlet. This must be a positive decimal number.

Overland Flow

• ELEVATION dataset –
  • Select – Opens Select dataset for ELEVATION dataset dialog. Must specify one for use in model.
• Solver(OVERTYPE) – Select one of the two following options from dropdown. Check any of the four following options if applicable.
  • "ADE" – Alternating Direction Explicit method.
  • "ADE-PC" – Alternating Direction Explicit Predictor-Corrector method. Completes most slowly, but is the most robust.
• ROUGH_EXP –
• INTERCEPTION – If selected, will use interception using data present in the Mapping Table file
• RETENTION – Selecting this specifies that a uniform retention depth is to be used for all overland flow cells.
• AREA_REDUCTION –

Infiltration

• Infiltration type – Select the method for calculating infiltration type from the drop down menu.
  • "No infiltration" – Select in order to not calculate any infiltration.
  • "Green & Ampt w/ soil moisture redistribution (INF_REDIST)" – Specifies infiltration calculations using Green and Ampt with Redistribution method - redistributes soil moisture during periods of no- or low- intensity rainfall
    • Soil moisture depth (SOIL_MOIST_DEPTH) –
    • Top layer depth (TOP_LAYER_DEPTH) –
  • "Green & Ampt multilayer (INF_LAYERED_SOIL)" – Specifies three layered Green and Ampt infiltration
    • Soil moisture depth (SOIL_MOIST_DEPTH) –
  • "Richards' infiltration (INF_RICHARDS)" – Select when using Richards' equation to simulate infiltration.
    • Weight (RICHARDS_WEIGHT) – Used to determine how much weight is placed on upper and lower cells using the arithmetic weighting method for calculating inter-cell hydraulic conductivities.
    • DTHETA MAx (RICHARDS_DTHETA_MAX) – Specifies maximum water content change allowable. Default value = 0.025.
    • C option (RICHARDS_C_OPTION) – Hydraulic conductivity and water capacity values dependent on water content of each cell. Select either brooks or havercamp
    • K option (RICHARDS_K_OPTION) – Inter-cell hydraulic conductivity weighting method - ARITHMETIC or GEOMETRIC
    • Upper option (RICHARDS_UPPER_OPTION) – Selections here compute the hydraulic conductivity at the ground surface - either green_ampt ( or average
    • Max Iteration (RICHARDS_ITER_MAX) – Maximum number of iterations specified by the user. Default = 1.
    • Max num. cells (MAX_NUMBER_CELLS) –
    • Soil moisture depth (SOIL_MOIST_DEPTH) – A decimal depth value in meters.

Channel Routing

• Channel routing computation scheme –
  • "No routing" –
  • "Diffusive wave (DIFFUSIVE_WAVE)" –
    • Allow overbank flow (OVERBANK_FLOW) – Selecting this allows the water in the channel to flow back onto the overflow plane when the stream elevation is above the top of the bank.
    • Allow overland backwater (OVERLAND_BACKWATER) – Selecting this option includes backwater effects on overland. . .
    • Outlet head BC (HEAD_BOUND / BOUND_DEPTH) – Enter a decimal value for the specified head boundary at the channel outlet.
    • Create hot start file – Check box to save a file containing soil moistures for every grid cell in the watershed after the simulation has run.
    • Start from hot start file – Check box in order to select a file containing starting surface moisture data for every grid cell in the watershed
    • Soil erosion (SOIL_EROSION) – Allows user to calculate overland soil erosion.
      • Sediment porosity (SED_POROSITY) – Enter the value of the porosity of the channel bed sediments. This value must be between 0.0 and 1.0. The default is 0.25.
      • Water temperature (WATER_TEMP) – Enter the value of the water temperature
      • Sand size (SAND_SIZE) – Enter the value of the representative grain-size of the sand.
    • Compute containment transport –
      • Decay coefficient (CHAN_DECAY_COEF) –
      • Dispersion coefficient (CHAN_DISP_COEF) –
      • Initial concentration (INIT_CHAN_CONC) –

Output – General

• Dataset write frequency (MAP_FREQ) –
• Hydrograph write frequency (HYD_FREQ) –
• Output units – Select the type of output unit needed for your results from the dropdown menu.
  • "English (QOUT_CFS)" – Select this option to show outflow hydrograph ordinates in ft³/s.
  • "Meters (METRIC)" – Select this option to show the outflow hydrograph ordinates in m³/s.
• Suppress screen printing (QUIET) – Selecting this option suppresses printing information to the screen each time step.
• Suppress long term simulation printing (SUPER_QUIET) – Selecting this option suppresses all printing of information to the screen. Useful in calibration mode.
• Strict Julian dates (STRICT_JULIAN_DATE) – Selecting this option makes all time series data output with strict Julian dates.
• Output contaminants (ALL_CONTAM_OUTPUT) –

Output – Gridded Datasets

• Distributed rainfall intensity (DIS_RAIN) –
• Surface depth (DEPTH) –
• Cumulative infiltration depth (INF_DEPTH) –
• Infiltration rate (RATE_OF_INFIL) –
• Surface soil moisture (SURF_MOIST) –
• Flood (max) depth (FLOOD_GRID) –
• Snow water equivalent (SNOW_SWE_FILE) –

Output – Link/Node Datasets

• Channel depth (CHAN_DEPTH) –
• Channel flow (CHAN_DISCHARGE) –
• Channel velocity (avg) (CHAN_VELOCITY) –
• Channel sediment flux (CHAN_SED_FLUX) –
• Flood (max) depth (FLOOD_STREAM) –
• Water surface elev (CHAN_STAGE) –
• Pipe flow (PIPE_FLOW) –
• Pipe node depths (PIPE_HEAD) –
• Pipe tile in/out flow (PIPE_TILE) –
• Superlink junction in/out flow (SUPERLINK_JUNC_FLOW) – Select to access the file containing the time series output data for junctions
• Superlink node in/out flow (SUPERLINK_NODE_FLOW) – Select to access the file containing the time series output data for the nodes

Precipitation

• Precipitation type: – Select one of the two methods for simulation
  • Uniform (PRECIP_UNIF) – Select this for uniform rainfall in both time and over every cell of the grid.
    • Start date/time (START_DATE,START_TIME): – Edit the calendar start date and start time.
    • Intensity (mm/hr) (RAIN_INTESITY): – Input how intense the rain is over the grid and during the simulation time. Uniform throughout.
    • Duration (min) (RAIN_DURATION): – Input the length of time in minutes the rain is falling for the simulation
  • Hyetograph –
    • Start date/time (START_DATE,START_TIME): –
    • Hyetograph: –
    • Edit XY Series... – Clicking this button brings up the XY Series Editor dialog which allows the user to import an XYS (.xys) file.
    • Average depth (mm): –