Periodic Wind Variations at 65-118 km at Saskatoon (52N)

Periodic time analyses of radio reflection winds from 65-118 km at Saskatoon (52 deg N), 1969-1976, confirm component waves' amplitudes and phases previously found by meteor-wind radar data at highest altitudes. These analyses also provide values down to meteorological rocket altitudes. The newest information is that the semiannual wave progresses downward at a very constant rate of 8 km/month from 118 to 70 km. The semiannual phase dates suggest that this wave may be caused by either or both (1) the influence of auroral particle precipitation maxima on heating by eventual effects on ozone, or (2) the influence of heating at high latitudes during sudden warmings. A three-month wave, also found, has twice the rate of phase progression as the semiannual wave. Significant spectral peaks are found near a period of 5 days, particularly in summer. At least half of the variance of data spaced at five-minute intervals is associated with variations of period less than about one-half hour, suggesting that sampling should be performed at the highest possible frequency.