Using data previously obtained by Muffatti (1963) and Weinert (1968) for the years 1956 to 1961 and new data covering the period 1962 to 1968 auto-correlation functions of wind speed along the axis of the sub-tropical jet stream at 200 m b in the Australian region have been estimated. From these functions seasonal values of a longitudinal length scale have been evaluated. It is found that the form of the auto - correlation function shows similarity between seasons and that there is a systematic variation in length scale with maximum values in autumn and spring and minimum values in summer and winter.
R. R. Brook (Tue,) studied this question.