Research Article

Methods to Estimate Surface Roughness Length for Offshore Wind Energy

Figure 4

Frequency distribution of surface roughness length during the 2013–2014 IMPOWR campaign using two sonic anemometers located at 12 m AMSL for (a) December-January-February (DJF); (b) March-April-May (MAM); (c) June-July-August (JJA); and (d) September-October-November (SON). The mean and median are displayed on each figure. The x-axis is logarithmic and the y-axis has different maxima in each figure.
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