Characteristics of seven lightning discharges that caused forest fires

The hypothesis that lightning fires are caused by a special type of lightning discharge has been presented several times in literature over the past 20 years. Working with laboratory sparks, McEachron and Hagenguth [1942] suggested that ignition by natural lightning is usually caused by a discharge having a long-continuing current phase. This view is widely accepted [Berger, 1947; Malan, 1963; Loeb, 1966], even though field corroboration has been almost nil. To the authors' knowledge, the two discharges and resultant fires documented by Norinder et al. [1958] are the only natural events reported to date wherein both the discharge and its ignition effects were documented.