Atmospheric Electricity

Atmospheric Electricity

The first edition of the textbook Physics of the Air by W. J. Humphreys was published in 1920 with a second edition appearing in 1929 and the third [and final] edition appearing in 1940.

William Jackson Humphreys (February 3, 1862 – November 10, 1949) was an American physicist and atmospheric researcher.

He worked in the fields of spectroscopy, atmospheric physics and meteorology.

In the field of spectroscopy he found the shift of spectral lines under pressure.

In atmospheric physics he found a very good model for the stratosphere in 1909.

He wrote numerous books, including a textbook titled Physics of the Air, first published in 1920 and considered a standard work of the time, though it was last published in 1940.

Physics of the Air was considered “a standard work” between the 1920s and 1940s and provides a wonderful insight into Atmospheric Science before the era of Settled Science.

This posting references the second edition [1929] of Physics of the Air [that can be read or download via the website] but it should be noted that the preface to the third edition [1940] notes that it “contains no radical departures from either the plan or the scope of the second” although the third edition does correct a few errors and includes some additional information.

The chapter on Atmospheric Electricity in this “standard work” is especially interesting because it discusses the potential gradient that was studied and observed during voyages of the Carnegie and Maud.

Potential Gradient near the Surface.
The vertical potential gradient near the surface of the earth, due to the total charge on the earth plus charges locally induced by clouds or otherwise, varies greatly with location, season, hour, and weather conditions.

It even reverses signs, frequently, during thunderstorms, but its general average over the sea and level land areas, during fine weather, appears to be of the order of 100 volts per meter, in response to a negative surface charge.

Location Effect.
Since the earth is a conductor, it is obvious that the distribution on its surface and the resulting vertical potential gradient will be so modified by topography as to be smaller in narrow valleys than on the neighboring ridges.

Over level regions of the same elevation, the gradient appears to be largest in the interior of continents of the temperate zones, and least within the tropics, and also, perhaps, in very high latitudes.

Annual Variation.
The annual variation of the vertical potential gradient near the surface of the earth differs greatly from place to place.

In general, it is comparatively small in tropical regions, and, also, everywhere on mountain tops, but large, as much in some cases as twice the annual average value, in the temperate zones where the gradient changes are, roughly, as follows: An increase during the fall and early winter to a maximum of perhaps 250 volts per meter, followed by a rapid decrease during spring to a moderately constant summer minimum of, roughly, 100 volts per meter.

Diurnal Variation.
The diurnal variation of the potential gradient, as illustrated by Fig. 140, after Bauer and Swann, changes with place, season and altitude.

Its amplitude is greater along middle latitudes, in the interior of continents, than along low latitudes, or anywhere over the ocean; greater during winter, when it is single crested, than summer, when double crested.

At moderate elevations, ½ kilometer or less, the gradient has only a single daily maximum and minimum, whatever its surface periods.

From the above facts, it appears that the single daily variation of the potential gradient is fundamental, and that the summer afternoon minimum, that develops a double diurnal variation, is only a shallow disturbance. Furthermore, quoting from Mauchly:

It is found that the preponderance of evidence from observations made aboard the Carnegie in each of the major oceans, indicates that the diurnal variation of the potential gradient over the oceans is primarily due to a 24-hour “wave,” which progresses approximately according to universal, rather than local, time. According to the mean yearly results, from all ocean observations to date, this primary wave has an amplitude of about 15 per cent of the mean-of-day value of the potential gradient and attains its maximum development at about 17.5h. g.m.t.

Diurnal Variation of Potential Gradient

And Whipple has added the significant fact that the diurnal variation of the electric potential gradient over the oceans coincides, roughly, with the like variation of the world’s thunderstorms.

It would seem, therefore, that there are two terms in this diurnal variation; one, dominant over continents, that runs with local time and presumably is due to local conditions; and another, dominant over the oceans, that follows universal time, and is owing, perhaps, to the occurrence of thunderstorms as affected jointly by insolation and the distribution of continents and oceans.

Potential Gradient and Elevation.
Measurements of the potential gradient from free balloons have shown that it varies greatly and irregularly through the low dust-laden stratum, and that above this layer it decreases less and less rapidly to a comparatively small value at an altitude of only a few kilometers.

If the surface gradient is 100 volts per meter, it may be 25 volts per meter at an elevation of 1.5 kilometers, 10 at an elevation of 4 kilometers, 8 at 6 kilometers elevation, with similar decreases for greater heights.

The potential difference between the earth and the highest atmosphere, commonly is estimated to be of the order of 1,000,000 volts.

Physics of the Air – W. J. Humphreys – 1929 – McGraw-Hill Book Company

Physics of the Air also examines atmospheric currents.

At least four different electric currents exist in the atmosphere two always, and everywhere, or nearly so, and two sporadically, in time and place.

These are:

a. The lightning discharge, roughly, 100 per second for the earth as a whole, with a transfer of 10 to 20 coulombs each.

b. Precipitation currents, or currents due to the falling of charged rain, snow, hail, etc.

The average strength of such current may be found from the rate of precipitation and charge, usually positive, per cubic centimeter, say, of the rain, or its equivalent in the case of snow or hail.

During non-thunderstorm rains, this current often averages about 10-16 ampere per square centimeter of surface.

During violent thunderstorms, however, it is far greater, even as much as 10-12 ampere per square centimeter for brief intervals has been reported.

c. Convection currents, due to the mechanical transfer of the ions in the atmosphere from one place to another by winds, including vertical convection.

The strength of such current per unit area, at right angles to the direction of the wind, is obtained by multiplying the wind velocity by the net density of the charge.

The value of p varies greatly, but through much of the atmosphere the convection current is of the order 10-16 ampere per square centimeter cross-section of the wind, per meter/second velocity.

d. Conduction current, due to the downward flow of one set of ions, usually the positive, and the simultaneous upward flow of the other in response to the vertical potential gradient.

The density of this current, or strength per square centimeter cross-section, may be computed from the potential gradient and the conductivity, or, with suitable apparatus, may be measured directly.

The average value of this conduction current is of the order of 2 x 10-16 ampere per square centimeter of, apparently, the entire surface of the earth.

It generally is less during the day than at night, and less in summer than winter; but always of such value that the sum total of the current for the entire earth is roughly 1000 amperes, sufficient to carry off the entire charge of the earth, 45 x 104 coulombs, in 7.5 minutes if it were not continuously replenished.

How this constant current, always, on the whole, in the same direction, is maintained – how the earth can so rapidly discharge and, yet, forever be equally charged, like a cataract always falling but never running dry – is the present most urgent problem of atmospheric electricity.

Physics of the Air – W. J. Humphreys – 1929 – McGraw-Hill Book Company

Humphreys further discusses this “most urgent problem” and outlines some possible solutions.

Origin and Maintenance of the Earth’s Charge

Numerous hypotheses have been made to account for the negative charge of the earth, and to explain how that charge is maintained in spite of the current that would exhaust it in a few minutes if it were not, in some way, continually replenished, but no explanation of either has yet been found that meets all the difficulties and is supported by observation and experiment.

Ebert attributed them to the positively charged air that comes out of the pores of the earth at the onset of low barometric pressure, and its diffusion by winds and by convection.

Lenard ascribed the normal gradient largely to the positive charging of the air by the spray of ocean waves.

Swann however, has shown that all theories of this kind are inadequate because, among other reasons, convection is too slow to get the positive ions well up in the atmosphere, where they are known to exist abundantly, before being neutralized by the negative earth-air current.

Since the atmosphere is all the time more or less ionized, it seems reasonable to suggest, as many have done, that particles of any appreciable size falling through it would leave it positively charged, owing to the higher velocity and, therefore, likelier capture of the negative ions.

This theory is weakened by the fact that, on the whole, more positive electricity appears to be brought down by rain and snow than negative.

On the other hand, much negatively charged rain does fall, and some, at least, of that which is positively charged on reaching the earth may be so owing to the mechanical capture of ions of both classes in its course through the air, in which the volume charge normally is positive.

Then, too, the large, or Langevin, ions that settle slowly are more numerously negative than positive.

The idea, therefore, that the conduction current of negative electricity, away from the earth, may be largely balanced by a gravity return has not yet been conclusively refuted.

Since both the earth and the upper atmosphere, 50 kilometers above the surface, say, and far beyond, are excellent conductors in comparison with the lower air, they constitute a fairly good, even if somewhat leaky, condenser.

Presumably, earth and upper air each promptly distributes world wide every charge it receives, except in so far as it may be bound by a localized charge in the intervening dielectric, or lower, air.

This dielectric between the condenser plates contains about 1800 thunderstorms all the time, and is ruptured by, roughly, 100 lightning discharges every second.

And since only 1 in 10, perhaps, of these discharges is to the earth, it appears likely that many of them are diffusely to the upper air that is so richly ionized presumably by insolation.

Furthermore, since the charges in a thunderstorm often get separated by winds, or otherwise, with their ions in great measure immobilized by attachment to cloud particles, it seems possible that their separate actions on the conducting upper air render it relatively rich in positive ions, and poor in negative, as the latter, being the more mobile, are the easier pulled down.

Evidently, there also is a tendency to produce the same electrical unbalance in the air below the clouds, but this is relatively ineffective owing to poor conductivity.

When the cloud droplets evaporate, their charges remain, but, presumably, now attached to the condensation nuclei, which thus become gross ions that, with excess negative charges, slowly settle by gravity to the earth.

In some such manner, perhaps, as here outlined, thunderstorms mainly have established, and maintain, a potential difference of about 1,000,000 volts between the earth and the highly ionized region of the upper air a difference that is small in comparison with those locally and temporarily produced by these storms within the dielectric between the conducting plates and that cause lightning discharges.

This concept may be very erroneous, but from it practically every important observational fact about atmospheric electricity, such as inverse relation of conductivity and potential gradient, effects of dust, fogs, wind, cloud, time of day, etc., may be deduced.

It is, therefore, at least an aid to the memory.

If we insist that gravity actions, such as the falling of rain, bring to the earth more positive electricity than negative, as many observations indicate, and hold with Simpson that lightning usually is positive from cloud to earth, and, finally, that most of the brush discharges from grounded objects are of negative electricity, a comforting explanation, then, is not so easy to find.

But even under these, or practically these, adverse conditions, theories have been evolved, especially the penetrating radiation theory of Swann, in which it is assumed that incoming radiation of high penetrating power not only produces ionization, as it is known to do, but also drives violently forward the electrons it detaches.

In this way, it is assumed, the earth is kept negatively charged to such value that the resulting conduction current is, on the average, equal and opposite to the downward driven corpuscular current.

Evidently, then, the maintenance of the earth’s electric charge still is the great problem in atmospheric electricity, but it should not, and probably will not, remain so, much longer.

Physics of the Air – W. J. Humphreys – 1929 – McGraw-Hill Book Company

In 1989 Lars Wåhlin [in his very readable Atmospheric Electrostatics] revisited the history of atmospheric electricity and the establishment of a new field of research: Fairweather Electricity

The first person on record to have suggested a relationship between electricity and lightning was an Englishman named D. William Wall (1708).

He noted a similarity between lightning and the crackling sparks produced by the rubbing of amber.

S. Gray (1735) and A.G Rosenberg (1745) both mention the similarity between lightning phenomena and electric fire produced by electricity machines in the laboratory; and in a book published in Leipzig 1746, J.H Winkler describes several resemblances between lightning and electricity.

During this time improved electricity machines and Leyden jars became readily available and a new era of electrical science was born.

Many more scientists, among them Benjamin Franklin, also questioned the nature of lightning, recognizing its similarity to the snapping sparks produced in the laboratory.

“How loud must be the crack of 10,000 acres of electrified cloud!” exclaimed Franklin.

In a letter to Dr. John Mitchel of the Royal Society in England, he enclosed a treatise, “The Sameness of Lightning and Electricity”.

According to Mitchel, the paper was read by the Society amidst laughter from its professed experts on electricity.

In 1751 several of his papers were published in England in book form and soon thereafter translated into French by the naturalist D’Alibard.

So intrigued was D’Alibard by the sentry-box experiment that he decided to put it to the test himself.

An experimental structure slightly different in design was erected outside Paris at Marly.

By the 10th of May, 1752 D’Alibard (1752) had successfully determined that thunderclouds are indeed electrically charged.

In America a few weeks later Franklin, unaware of D’Alibard’s success, performed his famous kite experiment.

It was a poor man’s experiment, simple and brilliant.

It demonstrated that lack of financial help is an insufficient deterrent to genius.

(One wonders if Dr. Franklin was advised, when looking for financial support, to go fly a kite).

In his kite experiment Franklin not only confirmed the electrical character of lightning but also, more importantly, found clouds to be negatively charged at the base and positively charged on top, thus forming giant electric dipoles floating around in our atmosphere.

The D’Alibard-Franklin experiments were repeated by many investigators and most noteworthy is perhaps L. Lemonnier (1752) who, with his more sensitive apparatus, discovered that weak electrical charges could be detected in the atmosphere in the absence of clouds.

He also noticed a difference in electric intensity during night and day.

The discovery of Lemonnier is important because it gave birth to a new field of research in atmospheric physics, namely “Fairweather Electricity”.

Chapter 1 – Atmospheric Electrostatics – Lars Wåhlin – 1989
Colutron Research Literature – Colutron Research Corporation – Boulder, Colorado

However, Lars Wåhlin concluded that the “most urgent question” raised by Humphreys “still remains to be answered”.

One crucial question still remains to be answered.

What causes the positive space charge in the atmosphere and how is the opposite negative charge maintained on the earth’s surface?

As mentioned before there are two schools of thought on this one in which all thunderstorms around the world are believed to charge the earth-atmosphere system (Wilson 1929) and a more recent theory proposed by the author (1973) which considers the electrochemical effect as a charging mechanism where negative atmospheric ions are preferentially captured by the earth’s surface leaving a space charge of positive ions behind in the surrounding atmosphere.

Both theories might be supported by the evidence of a small systematic diurnal variation in the fairweather field, which is believed to be related to the world-wide atmospheric convection activity.

The effect was first discovered in Lappland 1905 by Simpson whose findings were later augmented by Hoffmann (1923) and Mauchly (1923).

Diurnal variations in the fairweather field

The effect is illustrated in Fig. 15 where the average variation in the world-wide potential gradient is compared to the estimated world-wide convection activity at different times of day (by GMT).

The top graph shows the global variations in the electric field measured at sea in the absence of local disturbances such as pollution, fog, etc.

The top graph seems to coincide with the lower graph which gives an estimate of the world-wide convection activity produced by the heat of the sun during a diurnal period.

The steady convection over oceans, however, is thought to smooth out the electric field variations as is evident from the top graph.

Before discussing the electrochemical and global thunderstorm circuits as possible generators of the fairweather field, it is necessary to examine the global leakage current and its implications.

The Air to Earth Current
As already mentioned, the atmosphere is conducting and the earth’s electric potential or field must cause a current to flow in the atmosphere.

Since there is an excess of positive ions residing in the atmosphere and an opposite negative charge bound on the earth’s surface, charge must flow to earth in the form of a positive ion current.

Direct measurements of electric currents in the atmosphere are difficult if not impossible.

Therefore, ion current values at different altitudes are almost always computed indirectly from conductivity and electric field data by the use of Ohm’s law.

Direct current measurements can be made, however, at ground level by isolating a portion of the earth’s surface and measure the charge collected over a given time.

Several methods can be used (Wilson 1906, 1916, Simpson 1910, Mühleisen 1953 and Kasemir 1951) but in almost all cases the indirect current gives a value often twice as large as the direct method (Lutz 1939, Israel 1954).

Whipple (1932) pointed out that the discrepancy in currents can be explained by the fact that there is always convection and eddy diffusion in the atmosphere which will mechanically move charges upwards in the atmosphere thus generating a mechanical or convection current in the opposite direction of the leakage current (the Austauch generator).

As later explained, the question whether or not the convection and leakage current on the average are equal is crucial to the electrochemical charging theory and is a problem which has not yet been settled.

From direct current measurements it is possible to estimate the total fairweather current over the whole earth to be nearly 2000 amperes which corresponds to a current density of about 4 x 10-12 amperes per square metre.

Other charge transfer mechanisms in the atmosphere of importance are point discharges, precipitation currents and lightning discharges.

Point Discharge Currents
It is difficult to determine the total charge brought to the earth’s surface by means of point discharge currents under electrified clouds.

Wormell (1930) has made some estimates from the amount of charge brought down by a single point over a period of 4 years.

He made a guess that the total point discharge current around the world brings negative charge to the surface at a rate of about 1500 amperes which would supply about 75% of the total fairweather leakage current.

Other investigators give slightly lower values for the average point discharge current but not less than 25% of the fairweather current.

The source of point discharge currents are the electrified clouds which of course also bring charge to ground by lightning.

The point discharge current is, to a certain extent, canceled by the large amount of positive lightning flashes to ground and through positive charge reaching the earth’s surface by precipitation.

Precipitation Currents
The electricity of precipitation has played an important role in atmospheric research due to the belief that charging of precipitation particles in some way must relate to whatever charging mechanism is active in clouds.

Paradoxically, this is not always true because the final charge on a cloud drop is determined in the space between the cloud base and ground and is usually of opposite sign to the charge of the cloud base where it came from.

This peculiar phenomenon is called the mirror-image effect and is demonstrated in Fig. 16 by the two curves which show the change in electric field strength and amount of precipitation charge reaching the earth’s surface as a function of time.

The mirror-image effect

One can easily see that when the electric field goes negative (negative charge in the cloud base) the precipitation current becomes positive and vice versa.

As pointed out by Chalmers, a drop must take several minutes to fall from the cloud base to ground.

Since the precipitation charge changes with the potential gradient below the cloud, it must mean that the drops also obtain their final charge below the cloud or very near ground.

The electrochemical charging process can possibly explain the mirror-image effect if one assumes that the positive to negative ion concentration ratio near ground is affected by the strong electric field under the cloud.

For example, a positive charge on the earth’s surface, caused by a strong negative cloud charge above, would attract and remove part of the negative ion population near the surface.

The result would be a higher than normal positive to negative ion concentration ratio at lower levels.

When the positive to negative ion ratio exceeds 1.2 (see Fig. 11) it will produce a positive electrochemical potential on water drops falling through such a region as demonstrated by the Gerdien apparatus experiments in section 2.1.

On the other hand, a positive cloud charge above would reverse the effect because drops now fall through an environment containing a higher negative to positive ion concentration ratio which will generate negative electrochemical charges on their surfaces.

Other explanations of the mirror-image effect take the Wilson charging mechanism into consideration.

This charging mechanism is based on the idea that rain drops become electrically polarized when immersed in an electric field such as under an electrified cloud.

A negative cloud charge above will induce a positive charge on the top surface of a drop and the bottom surface will acquire a negative charge induced by the positive charge on the earth’s surface.

The total net charge on the drop, however, would remain zero.

As the drop falls through the ionized region below a cloud it would preferentially sweep up positive ions by its negatively-charged bottom.

Calculations, however, show that the Wilson mechanism is too feeble to account for the amounts of charge normally collected by drops (the Wilson charging mechanism is discussed further in Chapter 3).

In contrast to rain, precipitation currents carried to ground by snow are usually always negative under potential gradients between ±800 V/m (Chalmers 1956).

The total precipitation current around the earth is estimated to be about +340 amperes.

Lightning Currents
The charge brought to earth by lightning is estimated to average -340 amperes which would cancel the precipitation current.

It must be remembered that a mean current of -340 amperes represents the excess of negative charge over positive charge reaching ground by lightning and that the ratio of negative to positive ground strokes equals about 10:1.

The average current in a negative lightning stroke to ground is about 25,000 amperes but the total charge averages only 25 coulomb.

Positive ground strokes usually carry as much as 10 times more charge and current than do negative strokes although they are outnumbered by 10:1.

The ratio of negative to positive ground strokes seems to vary with global location.

It is believed that about 2,000 thunderstorms are active at one time around the earth which amounts to a total number of 50,000 thunderstorms per day.

The Electric Budget
Where does the energy of nearly 200 million watts come from that is required to maintain the earth-atmosphere electric fairweather field?

Are thunderstorms generating the fairweather field by leaking off positive charge from cloud tops to the conducting ionosphere and by bringing negative charge to earth in the form of negative ground strokes and point discharge currents?

Or is the electric charge on the earth’s surface maintained by the electrochemical charging mechanism in close collaboration with convection and eddy diffusion?

These are some of the basic questions that are still in need of answers.

Both mechanisms are, in the author’s opinion, certainly capable of supplying enough charge and energy to the earth-atmosphere system, but new ideas and more sophisticated measuring techniques are needed in order to find the right answers.

Chapter 2 – Atmospheric Electrostatics – Lars Wåhlin – 1989
Colutron Research Literature – Colutron Research Corporation – Boulder, Colorado

Callum Coats incorporated atmospheric layers and electricity into a conceptual model which he called the Terrestrial Bio-Condenser in his book Living Energies [1992].

According to my calculations there are at least four such levels where the temperature equals +4°C, at altitudes of about 3.5km, 77km, 85km and 175km.

Since there is water vapour in the atmosphere near these various altitudes in the form of cumulus and cirrus clouds (troposphere), nacreous clouds (stratosphere) and noctilucent clouds (mesosphere) as shown on fig. 6.3, we have a situation where a thin stratum of pure water may exist at each of these levels, which has a high resistance to the transfer of an electric charge.

In view of the presence of these various +4°C strata and water’s high dielectric value of 81, it could be postulated that their combined effect would act to create a natural bio-condenser, a condenser being a device with which an electric charge can be accumulated and stored.

Callum Coats - Bio-condenser - 1992

Atmospheric Science: Callum Coats Condenser

After the publication of Lars Wåhlin’s Atmospheric Electrostatics science has added red sprites, blue jets and elves to its roster of Transient Luminous Events.

The preferred usage is transient luminous event (TLE), because the various types of electrical-discharge phenomena in the upper atmosphere lack several characteristics of the more familiar tropospheric lightning.

TLEs generally last anywhere from less than a millisecond to more than 2 seconds.

TLEs have been captured by a variety of optical recording systems, with the total number of recent recorded events (early 2009) estimated at many tens-of-thousands.

The global rate of TLE occurrence has been estimated from satellite (FORMOSAT-2) observations to be several million events per year.

In the 1920s, the Scottish physicist C.T.R. Wilson predicted that electrical breakdown should occur in the atmosphere high above large thunderstorms.

In ensuing decades, high altitude electrical discharges were reported by aircraft pilots and discounted by meteorologists until the first direct visual evidence was documented in 1989.

Several years later, the optical signatures of these events were named ‘sprites’ by researchers to avoid inadvertently implying physical properties that were, at the time, still unknown.

The terms red sprites and blue jets gained popularity after a video clip was circulated following an aircraft research campaign to study sprites in 1994.

Big Red Sprite

Sprites are large-scale electrical discharges which occur high above a thunderstorm cloud, or cumulonimbus, giving rise to a quite varied range of visual shapes.

They are triggered by the discharges of positive lightning between the thundercloud and the ground.

Blue jets differ from sprites in that they project from the top of the cumulonimbus above a thunderstorm, typically in a narrow cone, to the lowest levels of the ionosphere 40 to 50 km (25 to 30 miles) above the earth.

In addition, whereas red sprites tend to be associated with significant lightning strikes, blue jets do not appear to be directly triggered by lightning (they do, however, appear to relate to strong hail activity in thunderstorms).

On September 14, 2001, scientists at the Arecibo Observatory photographed a gigantic jet – double the height of those previously observed – reaching around 70 km (43 mi) into the atmosphere.

The jet was located above a thunderstorm over an ocean, and lasted under a second.

The jet was initially observed to be traveling up at around 50,000 m/s at a speed similar to typical lightning, increased to 160,000 and then 270,000 m/s, but then split in two and sped upward with speeds of at least 2,000,000 m/s to the ionosphere whence they spread out in a bright burst of light.

On February 02, 2014, the Oro Verde Observatory of Argentina reported ten or more gigantic jet events observed over a thunderstorm in Entre Ríos south.

Gigantic Jet

ELVES often appear as a dim, flattened, expanding glow around 400 km (250 mi) in diameter that lasts for, typically, just one millisecond.

They occur in the ionosphere 100 km (62 mi) above the ground over thunderstorms.

Their color was a puzzle for some time, but is now believed to be a red hue.

ELVES were first recorded on another shuttle mission, this time recorded off French Guiana on October 7, 1990.

ELVES is a whimsical acronym for Emissions of Light and Very Low Frequency Perturbations due to Electromagnetic Pulse Sources.

This refers to the process by which the light is generated; the excitation of nitrogen molecules due to electron collisions (the electrons possibly having been energized by the electromagnetic pulse caused by a discharge from an underlying thunderstorm).

Transient Luminous Events

And in 1991 science added Terrestrial Gamma-ray Flashes [aka Dark Lightning] to its roster of electrical phenomena.

Dark lightning is a process similar to ordinary lightning that creates pairs of electrons and antielectrons (or positrons), and that produces gamma rays and relatively little (visible) light.

Since the amount of light created is so small, dark lightning is practically invisible to the human eye.

Terrestrial gamma-ray flashes (TGFs) are bursts of gamma rays produced in the Earth’s atmosphere. TGFs have been recorded to last 0.2 to 3.5 milliseconds, and have energies of up to 20 MeV.

It is speculated that TGFs are caused by intense electric fields produced above or inside thunderstorms.

Scientists have also detected energetic positrons and electrons produced by terrestrial gamma-ray flashes.

Dark Lightning

But the “most urgent problem” highlighted by Humphreys in 1929 still remains unanswered.

How this constant current, always, on the whole, in the same direction, is maintained – how the earth can so rapidly discharge and, yet, forever be equally charged, like a cataract always falling but never running dry – is the present most urgent problem of atmospheric electricity.

Physics of the Air – W. J. Humphreys – 1929 – McGraw-Hill Book Company

This is surprising because the Earth can generate a “constant current” in many ways.

Telluric currents are phenomena observed in the Earth’s crust and mantle.

In September 1862, an experiment to specifically address Earth currents was carried out in the Munich Alps (Lamont, 1862).

The currents are primarily geomagnetically induced currents, which are induced by changes in the outer part of the Earth’s magnetic field, which are usually caused by interactions between the solar wind and the magnetosphere or solar radiation effects on the ionosphere.

Telluric currents flow in the surface layers of the earth.

The electric potential on the Earth’s surface can be measured at different points, enabling the calculation of the magnitudes and directions of the telluric currents and hence the Earth’s conductance.

These currents are known to have diurnal characteristics wherein the general direction of flow is towards the sun.

Telluric currents continuously move between the sunlit and shadowed sides of the earth, toward the equator on the side of the earth facing the sun (that is, during the day), and toward the poles on the night side of the planet.

An Earth battery is a pair of electrodes made of two dissimilar metals, such as iron and copper, which are buried in the soil or immersed in the sea.

Earth batteries act as water activated batteries and if the plates are sufficiently far apart, they can tap telluric currents.

Earth batteries are sometimes referred to as telluric power sources and telluric generators.

Faraday disk generator

A homopolar generator is a DC electrical generator comprising an electrically conductive disc or cylinder rotating in a plane perpendicular to a uniform static magnetic field.

A potential difference is created between the center of the disc and the rim (or ends of the cylinder) with an electrical polarity that depends on the direction of rotation and the orientation of the field.

It is also known as a unipolar generator, acyclic generator, disk dynamo, or Faraday disc.

The voltage is typically low, on the order of a few volts in the case of small demonstration models, but large research generators can produce hundreds of volts, and some systems have multiple generators in series to produce an even larger voltage.

The voltaic pile was the first electrical battery that could continuously provide an electrical current to a circuit.

It was invented by Alessandro Volta, who published his experiments in 1800.

Volta’s invention built on Luigi Galvani’s 1780s discovery of how a circuit of two metals and a frog’s leg can cause the frog’s leg to respond.

Volta demonstrated in 1794 that when two metals and brine-soaked cloth or cardboard are arranged in a circuit they produce an electric current.

In 1800, Volta stacked several pairs of alternating copper (or silver) and zinc discs (electrodes) separated by cloth or cardboard soaked in brine (electrolyte) to increase the electrolyte conductivity.

Salt Water Battery

WikiHow – How to Make a Homemade Battery

EZ Battery

Water as a transducer of energy
The Fourth Phase of Water – Dr. Gerald Pollack – 2013 – Ebner & Sons

Gallery | This entry was posted in Atmospheric Science, Earth, Electric Universe, Gerald Pollack, Water. Bookmark the permalink.

8 Responses to Atmospheric Electricity

  1. Excellent reference, and C14 – I wonder if it is routinely and continuously produced by terrestrial lightning? If so another settled science axiom seems doomed.

  2. A problem is the assumption of an electrically closed earth-system though the diurnal potential change could be linked to diurnal IR affecting the oceans, we still have the problem of -ve leaving earth, +ve entering earth; this problem is solved if we assume the earth (as a capacitor) in circuit with the solar circuit in which +ve charge leaves the sun passing though all planets on the ecliptic, to the heliopause, while -ve charges come from the heliopause along the ecliptic through the planets to the sun and thence onwards to the galactic circuit.

    AND from Irving Langmuir’s experiments, any electrically conductive object placed in a cell of plasma automatically develops a charged double layer between it and the plasma enveloping it. Spontaneous double layers develop as a ‘coating’ or envelope between the body and the immersive plasma. Modulations of the solar circuit then produce earth-modulations aka weather.

  3. Pingback: Atmospheric Electricity | Louis Hissink's Crazy World

  4. omanuel says:

    Thank you for excellent information about atmospheric electricity.

    Obviously we cannot understand the reason’s for changes in Earth’s climate if we ignore:

    1. Atmospheric electricity, and
    2. Source of energy energy [1].


    1. “Solar energy,” Advances in Astronomy (submitted 1 Sept 2014) or

    “Solar Energy for teachers”

  5. ggladyshev says:

    It is a very good article. Burning nitrogen in electrical discharges explains some problems of atmospheric chemistry. Burning nitrogen in the fireball is considered in the article “A Physico-Chemical Model of Ball Lightning”

  6. RdM says:

    Hard to find a place to leave an OT comment, but maybe here:
    Re Auroras, this may be new information of interest?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s