Observations of the spatial and temporal distribution of lightning flash sizes

Abstract:

Recent work has shown that lightning flash sizes exhibit organization that parallels the meteorological organization of thunderstorms. Two- or three-dimensional grids of flash size and rate allow for spatial diagnosis of actively convecting regions and those with advection- or sedimentation-dominated motions. A time series of statistical moments of the flash size distribution is useful in discrimination of stages in the cellular lifecycle. Finally, ensembles of flashes exhibit a scale-dependent distribution of electrical energy like that of a turbulent energy cascade. The role of turbulence in organizing charge into small pockets is under ongoing investigation as part of the Kinematic Texture and Lightning Experiment (KTaL), where the primary observational tools are the TTU Ka-band mobile Doppler radars and the West Texas Lightning Mapping Array. Preliminary results from these new field observations will be discussed and used to illustrate the methods of interpretation described above.