In the published version of figure 7 errors were unfortunately introduced in the data sets shown. Figure 7 should be replaced by the figure shown below. The publisher apologises to the authors, editors and readers for this error.
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Figure 7. The streamwise velocity variance for all smooth- and rough-wall data. A linear abscissa is used in (a) and a logarithmic abscissa is used in (b). In the inset of (b), the highest Reynolds number smooth-wall profile (
${\it\delta}_{99}^{+}=21\,430$
) is compared to the highest Reynolds number rough-wall profile (
${\it\delta}_{99}^{+}=29\,900$
).