ABSTRACT
All of the measurements mentioned above require these two conditions before any such analyses of the data are valid. In wind-tunnel tests, the separation of the micro-and macroclimatological parts of the spectrum is induced. This in turn creates a condition in which stationarity of the remaining turbulent spectrum is much easier to achieve. The investigator in the field has no such luxury. He or she must attempt to remove the nonstationary data before beginning the analysis. It is a salutary warning that, in reviewing many of the largest studies of wind observations, the mention of tests for stationarity is one of the rarest events reported.
