Profiles of turbulence statistics in and above an urban street canyon

摘要: Results from an extensive urban climate study are presented. Eighteen months of continuous measurements mean variables and a total 131 runs turbulence at various heights within above street canyon analysed. Scaled profiles wind speed also the velocity variances found to be strongly stability dependent. In air is consistently warmer than in upper part roughness sublayer well mixed with respect temperature. On average, near-neutrally stratified night unstable during day. The scaled exhibit strong dependence on stability. vertical component, particular, decreases height near-neutral stratification while increasing under conditions. Although spectra mid-roughness have similar shape as established non-urban surface layer spectra, − 23 slope high-frequency end, no inertial subrange observed, since ratio horizontal spectral densities does not approach required value 43 Furthermore, peaks both temperature occur much higher frequencies expected for standard conditions. Closer roof level inside canyon, energy shifted become flatter.