From A.F. Webb
Might the mysterious “sprites” seen high above some thunderstorms (“Bolts from the blue”, 19 August) be connected with the ionospheric phenomenon known as sporadic E? This consists of drifting, cloud-like patches of intense ionisation with a lifetime of a few hours, which are detectable because of the enhanced range they provide for VHF radio. Their source has long been a mystery, although I believe that thunderstorms have been suggested.
On the subject of thunderstorms, I wonder if any of your readers have seen a rather odd effect that I noticed some years ago. A streak of lightning seemed to break up into a regular “string of beads”. I would guess that there were around a hundred of them, evenly distributed along the length of the streak. I don’t think that it was a dazzle effect, as the streak wasn’t very vivid. I would be interested to know whether this is a known phenomenon, and if so, whether any explanation has been offered.
