Effects of mesoscale surface thermal heterogeneity on low-level horizontal wind speeds

When the amplitude is 200W m⁻², wind speeds induced by the surface-flux variations on scales of 16 and/or 32 km have multiple temporal oscillations from 0600 to 1800 local standard time.

The positive peaks first appear before noon. In contrast, for wind speeds induced by the 128-km surface heterogeneity, a single oscillation occurs in the late afternoon, which is much larger than those generated by the 16- and 32-km surface heterogeneity. In addition, at the oscillation onset the kurtosis of the velocity increment over a distance of 1 km significantly increases, which implies intermittency in the generation of 1-km scale eddies.