Variability of the Ground Electric Field under the Influence of Clouds of the Main Types according to Observations in Tomsk

Estimates of the variability of the electric field potential gradient under the influence of clouds of the main forms were obtained using meteorological and atmospheric–electrical observations over a 15-year period (2006–2020) in Tomsk. A comparative analysis and comparison of these estimates with similar estimates for electrically unperturbed atmospheric conditions (fair-weather conditions) was carried out. It was found that clouds of all main forms, including the upper tier, have a significant effect on the surface electric field, leading both to a shift in the distribution of the potential gradient values towards negative values, and to a change in their dispersion. An analysis of the histograms of the surface electric field potential gradient values during the passage of the main precipitation-forming clouds (Cb, Ns, St, As) showed the presence of heavy tails in their distribution. In the distribution of the potential gradient during the passage of nimbostratus clouds, a clearly expressed secondary mode is observed, which, presumably, may be associated with the development of masked convection.