Electric fields produced by lightning discharges

Abstract

The time domain electric field produced by the model lightning discharges in the neutral atmosphere is computed and its modifications due to geometrical changes of the stroke are examined. The combined effect of the motion of the current wave and the bending of the lightning channel results in multiple pulses. The vector of the electric field in the atmosphere acquires transient vertical inward/outward and sideways components. Therefore the vector “scans” the sky at the onset of the pulse. The effects are unobservable at the ground surface or right above the stroke. To detect these features, the airborne measurements should be performed at a distance of tens of kilometers from the discharge and at as high an altitude as possible. Quasi‐static, induction, and radiation field components of a severe stroke may trigger the modifications in the atmosphere. Simultaneously, disturbances above the storm may lead to the air density and temperature fluctuations that facilitate the initiation of the plasma processes. Since both the atmospheric disturbances and the focusing electric fields are enhanced at the periphery of a thunderstorm the luminous structures should be expected there at some distance from the parent strokes.