Correlation between airtemperature and thunderstorm activity in Africa according to the ELF measurements in Antarctica, Arctica and Ukraine

Abstract

<i>Purpose</i>: Search for the connection of seasonal variations in characteristics of the Earth-ionosphere global resonator with air temperature in Africa. Comparison of results obtained in Arctica, Antarctica and in the midlatitudes of the Northern Hemisphere with the surface temperature of African continent. Checking the effectiveness of the point source model for describing the seasonal change in the position of regions with the greatest thunderstorm activity.<p>

<p><i>Design/methodology/approach</i>: The method of correlation analysis of time series was used. According to the long-term monitoring of the natural noise of the extremely low frequency (ELF) range at the Ukrainian Antarctic Station (UAS), at the Low Frequency Observatory of the Institute of Radio Astronomy, National Academy of Sciences of Ukraine in Martove village (Ukraine), as well as at the SOUSY observatory (Spitsbergen), seasonal changes in the level of the first mode of Shumann resonance was restored by the activity of the African thunderstorm center. The average air temperature in the African continent over the same period was estimated according to the global network of meteorological stations. When estimating the intensity of the resonance maximum of extremely low frequency radiation, a correction has been introduced for the distance to the source of lightning discharges.<p>

<p><i>Findings</i>: The presence of a strong relationship between the surface air temperature of the equatorial and sub-equatorial regions of Africa and the intensity of the Schumann resonance generated by the African thunderstorm center is shown. It is shown that the model of an effective point source adequately describes the seasonal behavior of the African thunderstorm center.<p>

<p><i>Conclusions</i>: The developed technique can be applied at various receiving points for studying all continental thunderstorm centers. Such an approach will be useful for developing the concept of using the Schumann resonator as a “global thermometer”. Simultaneous observations in several receiving points can become promising also for estimating shorter (several days) variations in global temperature.