Mid-latitude atmosphere and ionosphere connection as revealed by very low frequency signals

• First time study of correlations between VLF amplitude and atmospheric parameters.
• High correlations observed for mid-latitude paths compared to high and low latitudes.
• Results suggest that atmosphere–ionosphereconnection depends on latitudinal variation.

Quantitative information about the effect of atmospheric influences on the variability of upper mesosphere–lower ionosphere (UMLI) region is not clearly known yet. To investigate the relationship between the lower atmosphere and UMLI region, we compared the amplitude of very low frequency (VLF) signals with the atmospheric parameters such as total column Ozone (TCO) density and stratospheric temperature at various heights for the first time for three different latitudinal regions. We show that the VLF amplitude is strongly correlated with the TCO density, stratospheric temperatures for mid-latitude propagation paths throughout the years. For high and low latitude regions, this correlation between the VLF amplitude and atmospheric parameters is poor and not significant. This study indicates the experimental observation of latitudinal dependence of atmospheric influence on the upper mesosphere.