Derivation of Vertical Wind and Turbulence Profiles, the Mixing-Layer Height, and the Vertical Turbulent Exchange Coefficient from Sodar and Ceilometer Soundings in Urban Measurement Campaigns - Meteorological and Air Quality Models for Urban Areas - page 123

(a)
(b)
Fig. 13.3 Variance of vertical wind component over Budapest (a) diurnal cycle and (b) with height
13.2.4 Turbulent Viscosity
An important variable in turbulence parameterizations for mesoscale numerical
models is the vertical turbulent exchange coefficient. This quantity is identical to
the turbulent viscosity of the atmosphere. An attempt to derive the vertical profile
of the vertical turbulent exchange coefficient from sodar measurements is displayed
in Fig. 13.7. Theoretically, the turbulent viscosity could be derived from the ratio
of the vertical turbulent momentum flux and the mean vertical wind speed gradient.