Spatial Intermittency of Surface Layer Wind Fluctuations at Mesoscale Range

We study various hourly surface layer wind series recorded at different sites in the Netherlands by the "Royal Netherlands Meteorological Institute." By reporting all velocity magnitude correlation coefficients, associated with the available couples of locations, as a function of their spatial distance, we find that they fall on a single curve. This curve turns out to be remarkably well described by a logarithmic shape, characteristic of continuous cascades with an intermittency coefficient λ2 ≃ 0.04 and an integral scale L ≃ 600 km. Along the same line, we study the scaling properties of spatial velocity increment structure functions. This allows one to estimate the ζ(q) spectrum and to confirm an intermittent nature of mesoscale fluctuations similar to the one observed in fully developed turbulence.