drag {ocedata}

Wind drag coefficient

Description

drag holds wind drag coefficients for wind-profile and eddy-covariance methods, summarized in Figure 3 of Garratt (1977). The data are stored in a data frame with four columns: U is wind speed in m/s; Cd is for (neutral) drag coefficient; n is the number of data measurements represented by the value; and method is a factor with two levels: profile and eddy, for two methods of inferring Cd.

Usage

data(drag, package="ocedata")

Details

The data were digitized from Figure 3 of Garratt (1977) by Dan Kelley.

References

J. R. Garratt, 1977. Review of drag coefficients over oceans and continents. Monthly Weather Review, 105:915-927.

Examples

data(drag, package="ocedata")
par(mar=c(3,3,1,1), mgp=c(2, 0.7, 0))
plot(drag$U, drag$Cd, pch=ifelse(drag$method == "profile", 1, 19),
    xlab="U [m/s]", ylab=expression(C[D]),
    xlim=c(0, 22), ylim=c(0, 3e-3))
legend("topleft", pch=c(1,19),
    legend=c("profile method", "eddy covariance method"))