Fig. 7

(a) and (b) etalon gap drift estimated from and , respectively, in units of wind velocity, (c) fitting error (standard deviation of the difference between the fitted Gaussian functions and the observed counts in percent of the peak counts; only the maximum of four directions is indicated), (d) peak height of the fringes in unit of counts per each CCD pixel, and (e) vertical, (f) eastward, and (g) northward wind velocities, measured by FP01 for 557.7-nm airglow at Tromsø on January 24, 2009. The values for the 10 fringes are overplotted in (a)–(d), while averages of the 10 fringe values are indicated in (e)–(g). The random errors of wind measurement estimated from the standard deviations of the 10-fringe values are indicated by error bars in (e), (f) and (g).