A VERIFICATION OF SOME METHODS TO DETERMINE THE FLUXES OF MOMENTUM, SENSIBLE HEAT, AND WATER-VAPOR USING STANDARD-DEVIATION AND STRUCTURE PARAMETER OF SCALAR METEOROLOGICAL QUANTITIES

A set of micro-meteorological data collected over a horizontal, uniform terrain the plain of La Crau, France) in June 1987 is analysed. Conditions were predominantly sunny and arid, while due to the ''Mistral'' the wind speed could exceed 10 m/s. Verification of several methods to evaluate surface fluxes of heat, momentum and water vapour from the standard deviation of temperature, wind and specific humidity is presented. Also, a similar approach using the structure parameter of temperature is considered. These methods are all based on Monin-Obukhov (M-O) similarity theory. It is found that the standard deviation of temperature, vertical and horizontal wind speed as well as the structure parameter for temperature behave according to M-O similarity. It is shown that the sensible heat flux and friction velocity can be determined from a fast response thermometer and a cup anemometer. Also, it appears that the analytic solution of the set of governing equations as derived by the first author yields good results. M-O theory does not appear to work for the standard deviation of specific humidity. This may be due to the relative importance of large eddies.