uh function

Unit hydrograph estimation

Estimate the unit hydrograph from a sample of hydraulic lengths and a streamflow velocity.

uh(hl, ...)

## Default S3 method:
uh(hl, uc, deltat, ...)

## S3 method for class 'units'
uh(hl, uc, deltat, ...)

## S3 method for class 'stars'
uh(hl, ...)

## S3 method for class 'transfR'
uh(hl, verbose = TRUE, ...)

Arguments

• hl: hydraulic length of class stars, matrix, vector or transfR. If no unit is provided, hl is assumed to be in [m].
• ...: further arguments passed to or from other methods
• uc: streamflow velocity. If no unit is provided, uc is assumed to be in [m/s].
• deltat: time step of the time series. If no unit is provided, deltat is assumed to be in [min].
• verbose: boolean indicating if information messages should be written to the console

Returns

A data.frame with vectors of class units, or if hl is a transfR object, the same transfR object incremented by the "uh" attribute.

Details

The function estimates the unit hydrograph from geomorphometric information. A travel time to the outlet is estimated by assuming an average streamflow velocity (uc) within the river network and by applying uc over the sample of hydraulic lengths (hl). The unit hydrograph is the probability distribution of this travel time to the outlet given at each time step (deltat).

Examples

data(Oudon)
uh1 <- uh(hl=Oudon$hl[[1]], uc=units::set_units(0.5,"m/s"),
deltat=units::set_units(1,"h"))
plot(units::set_units(uh1$max_time,"h"), cumsum(uh1$prob), type = "b",
xlab = "Travel~time", ylab = "Probability~of~non-exceedance")

object <- as_transfr(st = Oudon$obs, hl = Oudon$hl)
object <- velocity(object)
object <- uh(object)
plot(object, i = 1, attribute = c("uh"))