The Origin of Thunderstorm Charge Separation: Structural asymmetry and directional electron capture in ice–graupel collisions
The preprint version is available on SSRN: The Origin of Thunderstorm Charge Separation: Structural Asymmetry and Directional Electron Capture in Ice-Graupel Collisions (August 17, 2026). http://dx.doi.org/10.2139/ssrn.7309279 T he O rigin of T hunderstorm C harge S eparation Structural asymmetry and directional electron capture in ice–graupel collisions Juliet Zhong Independent Researcher, London, United Kingdom. ORCID: 0009-0006-5099-3671 | August 2026 Abstract The microscopic origin of charge separation during collisions between ice crystals and graupel in thunderstorm clouds is a longstanding open problem. Recent measurements establishing that hexagonal ice is a strong flexoelectric material suggest one candidate mechanism, but any mechanism rooted in an intrinsic, season-independent material property must still explain why global lightning frequency is governed by convective intensity, peaking sharply in local su...