superPos {berryFunctions}R Documentation

superposition of discharge, unit hydrograph


superposition of precipitation along unit hydrograph (to simulate Q from P)


superPos(P, UH)



Vector with precipitation values


Vector with discrete values of the Unit Hydrograph. This can be any UH summing to one, not just the storage cascade model.


Vector of streamflow values


Berry Boessenkool,, July 2013

See Also

lsc where superPos is used, unitHydrograph


N <- c(9,5,2,14,1,3) # [mm/hour]
UH <- c(0, 0.1, 0.4, 0.3, 0.1, 0.1) # [1/h]
sum(UH) # sum must be 1

superPos(N, UH)
# If catchment area = 34 km^2 and precipitation is homogenous:
superPos(N/10^3, UH) * 34*10^6 / 3600  # m^3/s  # Add baseflow and you're done...

SP <- data.frame(Prec=c(N, 0,0,0,0,0),
          P1=c( UH*N[1], 0,0,0,0,0),
          P2=c(0, UH*N[2], 0,0,0,0),
          P3=c(0,0, UH*N[3], 0,0,0),
          P4=c(0,0,0, UH*N[4], 0,0),
          P5=c(0,0,0,0, UH*N[5], 0),
          P6=c(0,0,0,0,0, UH*N[6] ),
          runoff=superPos(N, UH))
SP # SuperPosition

SPcum <- t( apply(SP[2:7], 1, cumsum) )

plot(N, type="h", col=2:7, lwd=3, xlim=c(1, 10), ylim=c(30,0), lend=1)
plot(1, type="n", ylim=c(0, 15), xlim=c(1, 10), axes=FALSE, ann=FALSE)
axis(4, las=1)
polygon(x=c(1:11, 11:1), y=c(SPcum[,1], rep(0, 11)), col=2)
for(i in 2:6) polygon(x=c(1:11, 11:1), y=c(SPcum[,i], rev(SPcum[,i-1])), col=i+1)
text(3.5, 1, "Shape of UH")
lines( superPos(N, UH), lwd=3)

plot(UH, type="o", ylim=lim0(0.4), las=1)
lines(UH, type="h" )

# Effect of distribution of Prec:
P_a <- c(1,2,3,4,5,6,7,8)
P_b <- c(4,4,4,4,4,4,4,4,4)
P_c <- c(8,7,6,5,4,3,2,1)
sum(P_a) ; sum(P_b) ; sum(P_c)

UH_1 <- unitHydrograph(n=2, k=2.3, t=1:25)
UH_2 <- unitHydrograph(n=5.5, k=1.8, t=1:25)

par(mfrow=c(2,3), mar=c(2,3,2,1), las=1)
plot(P_a, type="h", col=3, lwd=3, ylim=c(0,8), main="Precipitation a")
plot(P_b, type="h", col=4, lwd=3, ylim=c(0,8), main="Precipitation b")
plot(P_c, type="h", col=5, lwd=3, ylim=c(0,8), main="Precipitation c")
plot(UH_1, type="l", main="unit hydrograph", ylab="",xlab="Zeit")
lines(UH_2, col=2)
text(c(7,14), c(0.12, 0.07), c("UH_1","UH_2"), col=1:2)
plot( superPos(P=P_a, UH=UH_1), col=3, ylim=c(0,5), type="l",
      main="Discharge", ylab="Q [m^3/s]")
lines(superPos(P=P_b, UH=UH_1), col=4)
lines(superPos(P=P_c, UH=UH_1), col=5)
legend("topright", c("P a","P b", "P c"), title="with UH_1", col=3:5, lty=1)
plot( superPos(P=P_a, UH=UH_2), col=3, ylim=c(0,5), type="l",
      main="Discharge", ylab="Q [m^3/s]")
lines(superPos(P=P_b, UH=UH_2), col=4)
lines(superPos(P=P_c, UH=UH_2), col=5)
legend("topright", c("P a","P b", "P c"), title="with UH_2", col=3:5, lty=1)

[Package berryFunctions version 1.22.0 Index]