uStar: Calculates the water friction velocity, uStar

In rLakeAnalyzer: Lake Physics Tools

Description

uStar is the water friction velocity due to wind stress at the lake surface, it is calculated following the methods of Imberger (1985) as a function of the shear stress of air (Fischer et al., 1979), drag coefficient for momentum (Hicks, 1972), and a dimensionless constant (von Karman constant) that decribes the logarithmic velocity profile at the air-water interface

Usage

uStar(wndSpeed, wndHeight, averageEpiDense)

Arguments

wndSpeed	a numeric vector of wind speed in m s-1
wndHeight	a numeric vector of wind measurement height in m
averageEpiDense	a numeric vector of epilimnion density in kg m-3

Value

a numeric vector of uStar

References

Hicks, B.B., 1972. A procedure for the formulation of bulk transfer coefficients over water bodies of different sizes. Boundary-Layer Meterology 3: 201-213.

Amorocho, J., DeVries, J.J., 1980. A new evaluation of the wind stress coefficient over water surfaces. Journal of Geophysical Research 85: 433-442.

Fischer, H.B., List, E.J., Koh, R.C.Y., Imberger, J., Brooks, N.H., 1979. Mixing in inland and coastal waters. Academic Press.

Imberger, J., 1985. The diurnal mixed layer. Limnology and Oceanography 30: 737-770.

See Also

ts.uStar layer.density

Examples

  wndSpeed  <- c(5.1,6.3,6.3,5.2,7,7.2)
  wndHeight	<-	2
  averageEpiDense	<- c(14,15,14.2,13,12,12)

  cat('uStar for input vector is: ')
  cat(uStar(wndSpeed,wndHeight,averageEpiDense))

rLakeAnalyzer documentation built on June 10, 2019, 1:02 a.m.