Methods to Estimate Surface Roughness Length for Offshore Wind Energy

Figure 5

Examples of three types of observed, nonmonotonic wind speed profiles from the CW Historical data set and resulting log-fits using the statistical method: (a) Case 1 (zig-zag with positive wind shear and realistic ); (b) Case 2 (shearless with very low ); and (c) Case 3 (negative wind shear and very large ). The intercept of the log-fit (red line) and the y-axis represents the value in each figure.

(a)

(b)

(c)