Robert sent in the link to https://phys.org/news/2021-11-strong-power-electric-fields-upper.html … with the comment, a plasma wind = am electric current. The authors postulate a bottom up approach, he continues. Small tides generated near the surface can grow much larger when they reach the atmosphere. He suggests the reverse, a top down approach. There may of course be a bit of both. He says the winds are generated from external sources, which is not surprising as they are active in the ionosphere. The ionosphere is the positive electrode, he says, of a 'leaky capacitor' = the earth being the negative electrode. It would be interesting, he adds, if ICON can map the plasma winds. It might reveal 'wind' patterns resembling those of Jupiter. Such winds, according to Andrew Hall, once ravaged earth's surface. But when?
The paper is behind a paywall but you can see the abstract at www.nature.com/articles/s41561-021-00848-4 … 'Regulation of Ionospheric Plasma Velocities by Thermospheric Winds' in Nature Geoscience [2021]. Strong winds power electric fields in the upper atmosphere, according to NASAs ICON mission. A somewhat fascinating study that would have been rejected not so many decades ago as a flight of fancy. Even one decade ago they would have had problems. The ICON mission, we are told, represents the first direct measurements of earth's long theorised dynamo on the edge of space. However, they say a wind driven electrical generation that spans the globe 60 miles above the surface is a dynamo churning in the ionosphere. No wonder Robert was surprised. Are they talking about the Polar Wind – otherwise known as the auroral wind. This is earth's equivalent of the solar wind. Nowhere near as powerful as the solar wind – but then the earth is nowhere near as dynamic as the Sun. Or that is an alternative way of looking at it. Well worth some further research as Bikeland's tessera experiments may provide the answer. However, in spite of that, this is a gem as far as modern research is concerned. They are finding out discoveries that were predicted many years ago but were rejected by mainstream as impossible. Now, they are possible – and movement of opinion will continue as new discoveries are made.