Electricidad terrestreSe conocen tres sistemas eléctricos generados por procesos naturales. Uno está en la atmósfera. otro está dentro de la Tierra, fluyendo paralelo a la superficie, y el tercero, que traslada carga eléctrica entre la atmósfera y la Tierra, fluye en vertical.La electricidad atmosférica es el resultado de la ionización de la atmósfera por la radiación solar y a partir del movimiento de nubes de iones. Estas nubes son desplazadas por mareas atmosféricas, que se producen por la atracción del Sol y la Luna sobre la atmósfera. Suben y bajan a diario, como ocurre en el mar. La ionosfera constituye una capa esférica casi perfectamente conductora.Las corrientes de la Tierra constituyen un sistema mundial de ocho circuitos cerrados de corriente eléctrica distribuidos de una forma bastante uniforme a ambos lados del ecuador, además de una serie de circuitos más pequeños cerca de los polos. La superficie de la Tierra tiene carga eléctrica negativa. La carga negativa se consumiría con rapidez si no se repusiera de alguna forma.Se ha observado un flujo de electricidad positiva que se mueve hacia abajo desde la atmósfera hacia la Tierra. La causa es la carga negativa de la Tierra, que atrae iones positivos de la atmósfera. Al parecer, la carga negativa se traslada a la Tierra durante las tormentas y el flujo descendente de corriente positiva durante el buen tiempo se contrarresta con un flujo de regreso de la corriente positiva desde zonas de la Tierra con tormentas.
Recientemente vi en televisión que hablaban de algún tipo de relación entre terremotos y destellos luminosos en la atmósfera, al pasar la energía de los primeros al aire... algo así, pero no lo recuerdo bien.
IN some parts of the world, earthquakes are often accompanied by ball lightning, stroke lightning and sheet lightning1. The only causal connexion that seems possible is that the seismic strains of the earthquake somehow cause an electric field in the air, which in turn produces ball lightning2 and stroke and sheet lightning. What is the mechanism of this "seismoelectric effect" ?
Lightning discharges are known to accompany both earthquakes and volcanoes. The exact mechanism is not well understood. According to one source: "Transients luminous phenomena that may be due to electrical discharges have long been observed during earthquakes and speculatively attributed to the electric field generated by seismic strain." But that does not really tell us anything, does it?
Scientists in the United States, Europe, and Japan have scrutinized electrical data after the fact and have detected minute increases in electrical activity just before or during big quakes. They've suggested various alternative explanations for these findings, such as earthquake-triggered shifts in the water table or failure of power grids.
The precise mechanism, if such a phenomenon exists—as opposed to being coincidence with aurora or mistaken recall after a traumatic event such as an earthquake—is unknown. One theory suggests that earthquake lights are a form of plasma discharge caused by the release of gases from within the Earth and are electrically charged in the air, which might be confirmed by or simply related to the reports of steam venting out of the earth in recent Peruvian earthquakes.Another possible explanation is local disruption of the Earth's magnetic field and/or ionosphere in the region of tectonic stress, resulting in the observed glow effects either from ionospheric radiative recombination at lower altitudes and greater atmospheric pressure or as aurora. However, the effect is clearly not pronounced or notably observed at all earthquake events and is yet to be directly experimentally verified.[citation needed]Another explanation involves intense electric fields created piezoelectrically by tectonic movements of rocks containing quartz[9].Some similar clouds have been reported during nuclear tests [10] and radon is likely to be an earthquake precursor[11], so another theory is that glowing clouds might be light emission produced by ionization or plasma-chemical reactions[12]
...Observations of ionospheric electric fields and of the magnetic perturbations produced by ionospheric currents give us important information about thermospheric winds and about the interaction of the solar wind with the magnetosphere. Direct observations of thermospheric winds are relatively limited, but observations of magnetic perturbations exist for long periods of time at many locations around the Earth. When interpreted with the aid of simulation models of the ionospheric wind dynamo, magnetic data from sites at middle and low latitudes can provide a wealth of information about the distribution and variability of thermospheric winds on the sunlit side of the Earth. At high magnetic latitudes, observations of ionospheric electric fields and of magnetic perturbations on the ground and on satellites reveal characteristics of solar-wind/magnetospheric dynamo processes.At middle and low latitudes, winds in the ionospheric dynamo region tend to be dominated by global oscillations. Above 140 km, daily wind oscillations with magnitudes over 100 m/s are driven primarily by the absorption of far-ultraviolet solar radiation. Between 90 km and 140 km the oscillations are strongly influenced by upward propagating global waves, called atmospheric tides, that are generated by solar heating at lower altitudes: in the upper ozone layer (30-60 km) and in the troposphere (below 10 km). Gravitational tidal forcing by the Moon and Sun also contribute, but only in a minor way. As the tides propagate into regions of exponentially decreasing air density, their amplitudes can grow, reaching values of 100 m/s or so in the lower thermosphere before the waves are eventually dissipated. The generation and propagation conditions for these waves tends to favor the arrival of semidiurnal (12-hour) tides over diurnal (24-hour) tides in the dynamo region. Upward-propagating planetary waves with periods of 2-20 days are also believed to influence winds in the lower thermosphere, but their relative importance there has not yet been established. At high latitudes, electric currents drive thermospheric winds that at times can reach 1000 m/s or more in the upper thermosphere, both by the motor effect mentioned earlier, and by resistive heating of the gas that affects the pressure-gradient forces on the air. Variations in the sources of the winds, as well as variations in the propagation conditions of tides and planetary waves through the middle atmosphere (10-100 km), are responsible for variability of the thermospheric winds on a day-to-day, seasonal, and solar-cycle basis. Analyses of geomagnetic variations have revealed many properties of the winds and their variations. Since many of the geomagnetic measurements extend back in time for many decades, studies related to possible long-term global atmospheric change are feasible....
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