The discharge current waveforms produced by the electrostatic discharge of electron-charged polymethyl methacrylate (PMMA) were analyzed. The relevant parameters for characterizing the waveform morphology were extracted and investigated to build a functional model to describe and characterize these discharges. The model allows us to infer characteristics about the dynamics of the breakdown, including both one-dimensional and two-dimensional channel growth. We applied the model to the context of natural compact intracloud discharges (CIDs) by scaling the one-dimensional waveforms in size and time to those scales relevant to CIDs. We find that the discharge currents derived from electrostatic discharge events in electron-irradiated PMMA obey the same functional form of those of natural CIDs, leading to the conclusion that the PMMA-based discharges may a useful laboratory tool to reproduce CID discharge currents. We calculated the electric field that would be radiated by these scaled discharge currents using published measurement parameters for CIDs and found that the magnitude and pulse shape agree with observations very well.
