CONCERNING THE HORIZONTAL ELECTRIC-FIELD OF LIGHTNING

In lightning investigations we need simplied get reasonably accurate e xpressions for the horizontal electric field for an imperfectly conduc ting ground plant. The Cooray-Rubenstein (CR) prediction model involve s only the horizontal electric field expression for a perfectly conduc ting ground, the surface impedance, and the tangential magnetic field also for a perfectly conducting ground, Here we develop an exact versi on of this relationship and show analytically how and under what condi tions it reduces to the CR EXPRESSION.