Ionosphere-atmosphere coupling via stratospheric ozone

In this work the onset of the night-to-day phase transition in VLF signals, transmitted from Golfo Nuevo, Argentina (43 deg S, 65 deg W) and received at Atibaia, SP (23 deg S, 46 deg W), are studied in conjuction with ozone data from a Dobson spectrophotometer operated at Cachoeira Paulista, SP (22 deg S, 45 deg W), for the years 1977-1979. Meaningful values of the cross-correlation coefficients for trends of significant number of days, after eliminating the annual variation time series in both sets of data, have been obtained. The superposition of the lag-times of the correlation found for each year reveals a semiannual variation, which may indicate a meridional transport of ozone in the mesosphere assuming a significant role of the ionospheric D-region.