Comment on: ‘Are fast atmospheric pulsations optical signatures of lightning‐induced electron precipitation?’ by J. LaBelle

Abstract

LaBelle [1987] proposed that Fast Atmospheric Light Pulsations (FAPs), which have been observed at L=1.5‐2.2 in the northern hemisphere, are optical signatures of ≥2 MeV electrons associated with Lightning‐induced Electron Precipitation events produced by strokes in the southern hemisphere. FAPs cannot be produced by ≥2 MeV electrons in the inner radiation belt because the upper limit for fluxes of such particles is only about 0.2% of the value that was used in the analysis and the correct value results in an unrealistically short electron lifetime prediction. The discrepancy comes from using an electron model, AE‐2, which included the Starfish fission electrons. Additionally, the use of a model in which southern hemisphere lightning strokes result in northern hemisphere FAPs via a cyclotron mode interaction between magnetospheric electrons and lightning‐generated waves is also untenable because it would result in FAP intensities two orders of magnitude greater in the southern hemisphere than in the northern hemisphere, leading to a further two orders of magnitude reduction in estimated inner zone electron lifetimes.