Estimates of Level of the Global Lightning Activity Obtained from Schumann Resonance Monitoring

Schumann resonance measurements have been performed at Lekhta observatory during one year (from August 1999 to July 2000). The median dynamic spectra were constructed for the field components accumulated during the intervals one month long. Analysis of the spectra was performed from the point of view of global thunderstorm activity. The integrated estimates were obtained for the diurnal variations of the global thunderstorm activity and for seasonal changes in the thunderstorm centers.