Local Inflow Temporal Disaggregation
The Local Inflow Temporal Disaggregation category contains two methods: the default, no action method, None, and the Specified Factors method. These methods are described below.
The selected method is executed at the beginning of the run if the subbasin is enabled. The three disaggregation methods are always executed in the following order:
1. Local Inflow Spatial Disaggregation
2. Local Inflow Temporal Disaggregation
3. Incremental Local Inflows, which may or may not include forecasting.
NoneThis method is the default for the Local Inflow Temporal Disaggregation category and should be selected when temporal disaggregation of local inflows is not desired.
There are no slots specific to this method.
Specified FactorsThis method computes the Temporally Disaggregated Flow on all control points in the subbasin by multiplying the Distributed Flow value (monthly default) on each control point by the Temporal Disagg Factors (same timestep as run) located on the computational subbasin. There is one slot specifically associated with this method on the subbasin, the Temporal Disagg Factors slot. The other relevant data is held in method dependent slots on the control points and is accessed by the computational subbasin. See the Local Inflow Temporal Disaggregation on Subbasin method on the Control Point for details of these other slots.
The Specified Factors method sets the Temporally Disaggregated Flow slot on each control point to the product of the Distributed Flow value (on the control point) and the Temporal Disagg Factors value (on the subbasin). These values are set as input to avoid being cleared in subsequent model runs. After the temporal disaggregation is completed, all control points will contain a value in the Temporally Disaggregated Flow slot for all timesteps in the Temporal Disagg Factors slot.
The default timestep size for the Distributed Flow slot is 1 Month, however, this can be changed by the user by configuring the timeseries and is independent from the model timestep size. The user is responsible to ensure that the timestep size and the associated Temporal Disagg Factors data is appropriate. The timestep size for the Temporally Disaggregated Flow and Temporal Disagg Factors slots is always the same as that of the run control.
Slots Specific to This Method
Temporal Disagg Factors
Type: SeriesSlot
Units: Fraction
Description: Proportion of the Temporally Disaggregated Flow on an object (usually daily) to the Distributed Flow on the object (usually monthly). Generally, the Temporal Disagg Factors should average to 1.0 over the Disaggregated Flow’s timestep. For example, in the typical case, the daily Temporal Disagg Factors over any month should average to 1.0.
Information: Typically generated from historical data. The value must be greater than or equal to zero.
I/O: Required input
Links: Usually not linked
Model Setup
The computational subbasin must be set up for each subbasin in which flows will be temporally disaggregated. On the computational subbasin, select the Specified Factors method from the Local Inflow Temporal Disaggregation method category. Input data in the Temporal Disagg Factors slot on the computational subbasin. Append the relevant control points to the subbasin. Each temporal disaggregation subbasin should include all control points that will use the same Temporal Disagg Factors data for the disaggregation.
For each control point in the computational subbasin, the Specified Factors method must be selected from the Local Inflow Temporal Disaggregation category. If no values exist in the Distributed Flow slot (that is, if spatial disaggregation was not/ will not be performed) enter the necessary data.
Revised: 12/06/2024