Wild electrostatic speculations from staying up all night. Banish them from your head ...by typing them into SED!
During the formation of lightning leaders, sometimes the stepped leaders extend themselves quite fast. This looks instantaneous on those 7000fps youtube vids. Lightning RF then wouldn't be a big snap, instead it would be a crash, a roar of small pulses. That's got me thinking.
If normally lightning's various leader tips are like relaxation oscillators all stepping out of phase, then the RF output of lightning leaders in the VLF spectrum might be very low. Why? For each emitted pulse at zero phase, there's be a nearby leader emitting another pulse at 180. In the nearfield region (way below 100KHz) the RF might be strong, but there'd be very little farfield wave energy. Most of the emitted RF energy would be a hash of HF noise.
So, what if we synchronize the leaders? Blast the thunderstorm with, say, 30KHz vlf radiation. Any leader which was just about to step, would tend to step in synch with the "stimulating beam." Its propagating radiation would sum in phase, but only in the same direction as our broadcast. During the lightning strike, the thunderstorm would momentarily become a coherent VLF amplifier. Our beam of RF would be stronger on the far side of the t-storm. Like a huge load of NE2 pulsers, all flashing in synch with this "clock signal" we've given it. For a strong enough "clock" we might even synchronize some CG strikes, not just the leader steps.
OK, now let the amplified vlf wave circle the Earth and come back to hit the t-storm again (or hit some other ones.) During afternoon on the African coast the daily t-storms tend to triple the Earth's normal vertical DC e-field. That should be the best time to try this. Launch your cw vlf beam at Africa, see if it comes back from the opposite direction, only stronger.
So, rather than each lightning pulse having its VLF output canceled by a nearby unsynchronized pulse, all the pulses would lock onto our
30KHz clock. Give the global standing waves a kick, see if it becomes self-sustaining. If viewed in the RF spectrum, then the usual comb of Schumann Waveguide peaks would be reduced, and just one peak would be reinforced. The broadband t-storm noise gets harnessed to amplify our signal. And since the normal cancellation effect is removed, *more* t-storm vlf radiation would be emitted than usual. T-storm gets less heated by lightning, with more CW VLF output. It would be like turning an LED into a laser. (Or like putting some weakly glowing ZnS(Cu) phosphor into a tuned optical cavity. Big green flash, phosphor stops glowing.)So, does this whole thing happen naturally? The signature of the effect would be seen in the VLF Schumann spectrum. Peaks which normally show a waveguide resonator Q in the single digits, would suddenly show the enormous Q of an active sine oscillator. Phase noise of an oscillator is after all a bit narrower in freq than the bandwidth of a passive RLC.
Would there be any obvious phenomena caused by this? After all, the overall effect would be like being inside a microwave oven. RF driving of plasmoids? Disruption of e-layer? Maybe we'd see some weird aurora stripes far from the arctic. Oooo, if the initial "clock" was spontaneously initiated by a single t-storm, then the overall RF standing wave would appear as circular bullseyes with the storm at the center (plus a second hotspot pattern at the Earth antipode.) The VLF intensity might then be fairly low everywhere else, but grow to huge values near the triggering t-storm. Good reason why the phenomenon might only be rarely detected, even if it's not a rare event. But the RF wouldn't be coming from that storm, instead that storm would be "massaging" all the storms on Earth, and clocking them so they broadcast way more VLF than normal ...with the phase adjusted to beam their RF towards the triggering broadcast. Look for "impossible" electrical phenomena associated with t-storms. Any corona discharges created by that storm might start squealing in synch. (The freq could be low enough to be in the audio range. Or maybe cause all the dogs to howl or hide in the basement.) Barbwire fences might start arcing over, or their wires might get hot. Flourescent tubes could light by themselves if you took them outdoors (outdoors during a big thunderstorm of course.)