ScaleAquiferData: Scale 'AquiferData.txt' files to different model time steps

Description

ScaleAquiferData scales the RETRATE time step-dependent recession coefficient in an imported HYPE 'AquiferData.txt' file to a new target time step. See HYPE wiki tutorial on sub-daily time steps.

Usage

ScaleAquiferData(
  x = NULL,
  timestep.ratio = 1/24,
  digits = 3,
  verbose = TRUE,
  print.par = FALSE
)

Value

A data.frame() object as supplied in x, with re-scaled recession coefficients, or nothing if print.par = TRUE.

Arguments

x: Data frame containing HYPE AquiferData contents. Typically imported with ReadAquiferData().
timestep.ratio: Numeric, time step scaling factor. Defaults to (1/24) to scale from daily to hourly time steps. To scale from hourly to daily time steps use 24.
digits: Integer, number of significant digits in scaled parameter values to export. See signif().
verbose: Logical, if TRUE, then information will be printed.
print.par: Logical, print known time-scale dependent recession coefficients instead of scaling an AquiferData data frame.

Details

ScaleAquiferData applies a user-specified scaling factor timestep.ratio to the RETRATE time step-dependent recession coefficient in a HYPE AquiferData data frame. All RETRATE values that are not equal to zero are assumed to be aquifer rows and will be converted to the new time step. Recession coefficients are matched against an inbuilt set of column names. To see these names, call ScaleAquiferData(print.par = TRUE). Please notify us if you find any missing coefficients.

Timestep-dependent recession coefficients are scaled using the relationship described in: Nalbantis, Ioannis (1995). “Use of multiple-time-step information in rainfall-runoff modelling”, Journal of Hydrology 165, 1-4, pp. 135–159.

new_coefficient_value = 1 - (1 - old_coefficient_value)^time_step_ratio

Use the ScalePar and ScaleFloodData functions to scale the time-dependent parameters and recession coefficients in par.txt and FloodData.txt files, respectively. Note that ScalePar does not scale the values for the "gratk", "ilratk", "olratk", or "wetrate" rating curve recession coefficients in par.txt because they are not limited to the range 0-1. Likewise, HYPEtools does not provide any scaling function for the "RATE" columns in DamData.txt and LakeData.txt because these values are not limited to the range 0-1. We recommend looking at the results from the lakes/wetlands and recalibrating these parameters and their related power coefficients as needed.

Examples

Run this code

# Import daily HYPE AquiferData file
ad <- ReadAquiferData(filename = system.file("demo_model",
"AquiferData_Example.txt", package = "HYPEtools"))
# Scale to hourly time steps
ScaleAquiferData(x = ad)
# Print all time scale-dependent coefficients known to the function
ScaleAquiferData(print.par = TRUE)