On August 9, 1981, a series of three rockets were launched over an air mass thunderstorm off the eastern seaboard of Virginia while simultaneous stratospheric and ground‐based electric field measurements were made. The conductivity was substantially lower at most altitudes than the conductivity profiles used by theoretical models. Direct current electric fields over 80 mV/m were measured as far away as 96 km from the storm in the stratosphere at 23 km altitude. No dc electric fields above 75 km altitude could be identified with the thunderstorm, in agreement with theory. However, vertical current densities over 120 pA/m² were seen well above the classical “electrosphere” (at 50 or 60 km). Frequent dc shifts in the electric field following lightning transients were seen by both balloon and rocket payloads. These dc shifts are clearly identifiable with either cloud‐to‐ground (increases) or intercloud (decreases) lightning flashes.

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The first simultaneous electric field observations performed in the ionosphere and atmosphere over an active nighttime thunderstorm are reported here. In the stratosphere, typical storm‐related dc electric fields were detected from a horizontal distance of ∼100 km, and transient electric fields due to lightning were measured at several different altitudes. In the ionosphere and mesosphere, lightning‐induced transient electric fields in the range of tens of millivolts per meter were detected with rise times at least as fast as 0.2 ms and typical duration of 10–20 ms. The transients had significant components parallel to the magnetic field at 150 km altitude. This implies that either considerable Joule heating occurs or a collective instability is present because of the high drift velocities induced by the transient electric fields. Copious numbers of whistlers were genrated by the storm and were detected above but not below the base of the ionosphere. We present here the outline of a new model for direct whistler wave generation over an active thunderstorm based on these observations. The intensity of the observed two‐hop whistlers implies that they were amplified along their propagation path and suggests that particles were precipitated in both hemispheres.

A simple antenna for measuring the vertical electric field in the "middle atmosphere" has been flown on a number of rocket‐launched parachute‐borne payloads. We present here the data from the first nine such flights, launched under a variety of geophysical conditions, along with electrical conductivities measured simultaneously. The data include indications of layered peaks of several volts per meter in the mesospheric field at high and low latitudes in situations of relatively low conductivity. During an auroral "REP" event the electric field reversed direction in the lower stratosphere, accompanied by a substantial enhancement in conductivity. The data generally do not confirm speculations based only on the extension of the thunderstorm circuit from below or the mapping of ionospheric and magnetospheric fields from above, but seem to require, in addition, internal generation processes in the middle atmosphere.

In an attempt to explain numerous atmospheric electrical phenomena, the elements of the global electrical circuit are reexamined. In addition to being a "quasi-static "DC" generator" and source of radiated energy at VLF and higher, the thunderstorm is found to be a pulse generator, with most of the external energy contained in ELF and ULF pulse currents to the ionosphere (and Earth). The pulse energy is found to deposit largely in the middle atmosphere above the thunderstorm. The VLF and above components are well understood, as are the ULF components due to the conductivity gradient. However, a previously poorly understood ELF component on the millisecond timescale, or "slow tail," contains a large fraction of the electrical energyø This component couples strongly to the ionosphere and also launches a unipolar transverse electromagnetic (TEM) wavelet in the radial Earth-ionosphere transmission line. The increase in charge with distance associated with such wavelets, and their ensemble sum at a point, may explain some large mesospheric "DC" fields but there are still difficulties explaining other than rare occurences, except for antipodal reconvergence. These millisecond duration unipolar wavelets also couple to the ionosphere and may trigger other lightning at a distance. A schema is elucidated by which the charge of MeV particles deposited in the middle atmosphere persists for much longer than the local relaxation time. This also gives rise to unipolar waves of global extent which may explain lower-latitude field perturbations associated with solar/ geomagnetic eventso Introduction One of the best established "solar-terrestrial" relations is the observed short-term response of atmospheric electrical parameters (local "ionospheric potential," fair weather electric field and air-Earth current) to solar flares and related events, yet the classical "DC" picture of atmospheric electricity does not readily provide an explanation of such phenomena. To provide a framework for studying these phenomena, a reexamination of the elements of the "global circuit" is performed, and shows a coexisting "AC" or pulse circuit, with much more energy than that due to the "DC" or "radiated" components, and which may be more subject to "external" influences. Also considered is the coupling of this AC energy, most of which is at ELF/ULF frequencies, to the middle atmosphere, and to the ionosphere and "global circuit." It is suggested that some large mesospheric vertical fields, such as those observed by U.S. and Russian groups, may be due to unipolar transverse electromagnetic (TEM) wavelets propagating in the Earth-ionosphere cavity. These wavelets may explain the strong ELF/[JI,F spectrum in the Earthionosphere cavity and the mechanism by which high-energy particle precipitation events, as well as other lightning, may trigger lightning.The definition of the various frequency ranges used in this paper is the traditional definition which developed over many decades, in which ELF is in the range of about 10 to 3000 Hz, with UI.F below th...