Natural_time_increase: Natural_time_increase

In FannyVille/hydroSEG: Hydrograph segmentation and discretization between natural event or hydropeak

Description

#' Courret (2014) shows that in natural hydrology the rise and fall times of hydrographs follow an exponential law. Q= 4 * exp(-a * t^b) The value of the coefficient a can be expressed according to the module of the river. The value of the coefficient b is depends on the type of variation: increase or decrease Instead of reading the gradients graphically, this function gives directly by calculation an estimate of the shortest time to go from one flow rate to another.

Usage

Natural_time_increase(
  Stream_Module,
  Start = 50,
  End = 150,
  b_drop = 0.75,
  b_rise = 1.15
)

Arguments

Stream_Module	A numeric value corresponding to the average inter annual flow rate ""module"".
Start	A numeric value in this selection: 400, 350, 300, 250, 200, 150, 100, 75, 50, 25, 15, 10, 5, 4, 3, 2, 1, 0.5
End	A numeric value in this selection: 400, 350, 300, 250, 200, 150, 100, 75, 50, 25, 15, 10, 5, 4, 3, 2, 1, 0.5
b_drop	A numeric value of the coefficient b for decrease. By default b_drop = 0.75
b_rise	A numeric value of the coefficient b for increase. By default b_rise = 1.15

Value

a text informing of the fastest duration for increase

Examples

Natural_time_increase <- function(Stream_Module=10, Start=50,End=150, b_drop = 0.75, b_rise = 1.15)

FannyVille/hydroSEG documentation built on March 6, 2021, 12:23 a.m.