bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the ionization of the upper atmosphere
Authors: Swann W. F. G. 
Published: February 2008

The subject of the ionization of the upper atmosphere is one of extreme importance to students both of Terrestrial Magnetism and of Atmospheric Electricity, and from various points of view there are indications that this region of the atmosphere is to be treated as one of relatively high electrical conductivity. One of the first theories which took this hypothesis as one of its bases was that developed by Schuster1 to account for the diurnal variation of the Earth's magnetism.At the time when Schuster's paper was written the most natural source in which to seek an explanation of the high conductivity was the ultra‐violet light from the Sun. The great increase in our knowledge of photo‐electric ionization within the last few years renders it now possible to make a closer scrutiny of the consequences to be anticipated from the ultra‐violet ionization alone. Any conclusions as to the insufficiency of this source for accounting for such a conductivity as that cited by Schuster must not, of course, be considered in any way as a criticism regarding the broad principles underlying Schuster's work, since the ultra‐violet light is by no means the only source of ionization of the atmosphere. Indeed, Schuster himself questioned the sufficiency of this source, and he took pains to point out that other sources were available. Thus, the rate of production of ions in a closed vessel increases at altitudes of 10 kilometers to many times its value at the Earth's surface, and this fact suggests a powerful ionization agent in the upper atmosphere other than the ultra‐violet light. In spite of the existence of various agencies which may be invoked to account for the ionization in question, it is not without interest to discuss in terms of modern views as to photo‐electric ionization the possibilities inherent in the ultra‐violet light alone.
Remarks on non‐cyclic changes and calm days
Authors: Bauer Louis A. 
Published: February 2008

1. The foregoing article (pp. 69‐77) by Dr. Chree has particular reference to an item of the Madrid meeting of the International Section of Terrestrial Magnetism and Electricity pertaining to the application of non‐cyclic corrections in terrestial magnetism and atmospheric electricity which, owing to limited time, could not fully be discussed and regarding which no agreement was reached. Dr. Chree has concerned himself with the application of non‐cyclic corrections for a period of about two decades, but he has had few followers in the method adopted by him. It should be recalled that he has chiefly dealt with the discussion of the so‐called quiet days (limited to 5 per month in the case of terrestrial magnetism, and to 10, in atmospheric electricity).2. The mean values of results from the selected quiet days are frequently termed “normal” values, though, as a matter of fact investigations have repeatedly shown that the quiet clays are as subject to a special kind of disturbance, though to be sure to less extent, as are the greatly disturbed days. This fact is admirably shown in Father de Moidrey's timely article (pp. 79‐82). Instead of the quiet‐day values representing normal conditions they should be looked upon as representing subnormal conditions; it is as bad at times for a patient to have a sub‐normal temperature as a high temperature. On the average, about 65‐70 per cent of the five magnetically‐quiet days per month selected at the De Bilt Observatory, on the basis of characterization lists received from the operating observatories, are the days of minimum range in horizontal intensity. Sometimes it happens that a magnetic‐activity measure based on the assumption that the quiet days represent normal conditions turns out negative, and, hence, does not admit of physical interpretation. It has even occurred that the monthly mean diurnal range for the selected 5 quiet days was higher than the monthly mean diurnal range obtained from the 10 least disturbed days per month. We, accordingly, deem it safer in general, not to apply non‐cyclic corrections by Chree's method, with all the suppositions it implies, e.g., progressive linear change throughout the day, but we are quite ready to give all the information in our observatory publications which others may require for any procedure they may make themselves responsible for. Fortunately in terrestrial magnetism the “non‐cyclic” correction, as derived from differences of successive midnight values, is, in general, small, however, the case is entirely different in atmospheric electricity where the accidental or disturbing features may play a predominant part. We have repeatedly determined the Fourier coefficients from a series of diurnal‐variation observations extending over several months, or over several years, and have invariably found that the differences in the essential quantities, computed with or without application of a supposed non‐cyclic correction, are inconsequential from a physical standpoint.
The upper atmosphere
Authors: Maris H. B. 
Published: February 2008

Wind Currents and Diffusion—The components of a uniformly mixed atmosphere kept free from winds would separate by diffusion, heavier molecules moving down and light molecules moving up. The flow of separation would be uniform at all heights; for example, in the air 1.07×108 molecules of helium would be expected to move up past any horizontal square centimeter per second. This upward flow of the helium would establish gravity equilibrium for helium gas above 140 km in one day, above 120 km in five days and above 106 km in fifty days. Wind‐currents, it is estimated, would cause a movement of the air above 100 km to lower altitudes once in five to twenty‐five days.Temperature of the Upper Atmosphere—Radiation and absorption coefficients lead us to expect a temperature change of approximately 140° C between day and night during the summer and 30° C during the winter, at a height of 80 km. Carbon dioxide is found to be more important than water‐vapor in determining the radiant energy which escapes from the Earth's outer atmosphere, and the conclusions are reached that the ice‐ages can be explained by slight changes in the carbon‐dioxide content of the air.Density of the Upper Atmosphere—New tables of density are compiled which show helium‐content and hydrogen‐content roughly 1/100,000 of those previously calculated for heights greater than 130 km. The conclusion is reached that above 300 km the atmosphere can not be assumed to be in a state of equilibrium, but that the percentage of very high‐energy molecules would be far higher than would be given by a Maxwellian curve for thermal equilibrium.
A new theory of magnetic storms
Authors: Chapman S. , Ferraro V. C. A. 
Published: February 2008

6—The phenomena accompanying the advance of a solar ionized stream into the Earth's field.6.1—A stream of particles emitted nearly radially from an active area A on the Sun will have a curved form, on account of the Sun's rotation. The stream will lag slightly behind the solar radius through the emitting area A though each particle of the stream will move almost rectilinearly, approximately along the solar radius through the position of A at the instant of emitting that particle. The rate at which the lateral surface of the stream will approach the Earth, overtaking it in its orbital motion, depends only on the Sun's known angular velocity; the point of intersection of the Earth's orbit with the lateral surface of the stream moves relative to the Earth with a velocity of about 400 km/sec, thus traversing a distance equal to one Earth‐radius in about 18 seconds. If undisturbed by the Earth's field the stream would sweep across the Earth in about 35 seconds.
Measurements of total nuclei, of uncharged nuclei, and of large ions in the free atmosphere at Washington, D.C
Authors: Torreson O. W. , Wait G. R. 
Published: February 2008

In July and August, 1931, observations were made on the total and uncharged condensation‐nuclei in the free atmosphere on the grounds of the Department of Terrestrial Magnetism of the Carnegie Institution of Washington, in northwest Washington. The nuclei were measured before and after passing through a large‐ion counter between the tubes of which sufficient potential was applied (about 900 volts) to remove all charged nuclei with mobility of 1/3000 cm per second per volt per cm. From 21 sets of measurements, the ratio of uncharged to total nuclei (N0/NA) is found (after applying corrections for loss of nuclei while passing through the apparatus) to be 0.66, the mean value of N0 being 6,300 and the computed value of NA being 9,500. With potentials of 535, 890, and 1890 volts interchanged on the large‐ion tubes, practically no change occurred in No/NA, showing the mobility of the large ion to be not less than 1/1700 cm per second per volt per cm.In October and November, 1931, 77 measurements were made with the large‐ion counter on the number of electronic charges of one sign (positive and negative alternately) per cc in the atmosphere, simultaneously with measurements of total and uncharged nuclei. Small ions were removed from the air entering the large‐ion counter by a small‐ion counter attached to the intake. From these data N0/NA is 0.72, N±/NA is 0.14, N0/N± is 5.8 and the charge per large ion 1.10, the last figure being in good support of the generally accepted view that each large ion carries only one electronic charge. It is seen that NA = N0 + 2N±. The values of N0 and NA are more than double those found in July and August, being 15,000 and 21,000 nuclei per cc, respectively. These results are compared with the work of J. J. and P. J. Nolan, Scholz, Hess, and Israël, and evidence is found for believing that the ratio N0/NA increases in magnitude with increasing nuclei‐content of the air.A quite different analysis of the data obtained in October and November than was made for the above results is undertaken on the basis that N±/NA is not 0.14 but has instead two values, since 23 individual values fall closely around 0.20 and the remaining 54 around 0.10. The immediate conclusion is that the nuclei are at times doubly charged. From this point of view, the data are retabulated and re‐examined and it is found that the results do not show any inconsistencies which would preclude the possibility that doubly‐charged large ions were present almost exclusively on certain occasions and singly‐charged ones almost exclusive on other occasions during the observations here discussed.
The electricity of rain and thunderstorms
Authors: Gunn Ross 
Published: February 2008

Electricity of rain: It is shown that the observed properties of rain‐drops of very different histories are readily described if each water‐droplet and the surrounding ionized water‐vapor is considered an electrical concentration‐cell. The potential difference between the drop and points several radii outside approximate 0.06 volt. The equilibrium‐charge on each droplet is proportional to the radius and is positive if the droplet is evaporating and negative if it is condensing. These droplets grow by association into large rain‐drops and thus build up large charges of the order of 1/50 e.s.u. which discharge by conduction in a time of the order of 103 seconds. The drops thereafter take on an equilibrium‐charge depending upon the evaporation or condensation of the drop and its size. The calculated charges are in agreement with observation. A laboratory experiment verifying certain aspects of the predicted effects is described.A theory of thunderstorm‐electricity: It is shown that in the presence of a rapidly rising current of air and the formation of rain‐drops greater than a critical size, separation of charge takes place. At levels of condensation the atmospheric ions (usually positive) are swept to great heights while the newly‐formed rain (usually negative initially) falls. Both charge‐distributions discharge by conduction at different rates, leaving the charge in the zone of rain‐formation in excess (usually negative). The excess charge induces charges on the Earth or on the high conducting atmosphere of a magnitude equal to a large fraction of the excess charge. Rain‐drops formed by the association of droplets below the saturation‐level impart a normally positive space‐charge to the region. The charge‐distribution resulting from the separation is quantitatively calculated from physical data and agreement obtained with observation in regard to the potential differences, electrical field, electric moment, charging current, recovery‐time, and the average charge on the precipitated rain.Maintenance of the Earth's charge: Some objections to Wilson's thunderstorm‐theory of the maintenance are noted. It is shown that special thunderstorm‐conditions in mountainous regions are such that a total storm‐area of 0.01 per cent of the Earth's surface would precipitate sufficient negative charge on rain and transfer enough positive charge upward by convection to maintain the field. The possible importance of forced vertical convection over natural barriers in “fair‐weather” regions is considered and it is shown that such a systematic convection may account for an appreciable part of the necessary replenishing current.Distribution of free space‐charge: The factors determining the free space‐charge are considered and the resulting distribution of charge, electric field‐intensity, and potential are found.
Geomagnetic coordinates for the entire Earth
Authors: McNish A. G. 
Published: February 2008

During a recent investigation it was found necessary to construct a system of geomagnetic coordinates covering the entire Earth. As these may be found useful to those engaged in terrestrial‐magnetic, cosmic‐ray, and other geophysical researches for finding the geomagnetic coordinates of various places the nomographs prepared are reproduced herewith.Many magnetic phenomena are frequently found to have a relatively simple distribution when consideration is given to the location of the observing stations relative to the pole of the first‐degree harmonics of the Earth's general magnetic field. A coordinate‐system having this pole as its origin is called a system of geomagnetic coordinates. The term magnetic coordinates is sometimes used to denote this system but as magnetic coordinates are sometimes considered as deducible for a point from the magnetic elements at that point the former term avoids ambiguity in considering those based upon the general field. Thus, the magnetic meridian at a point is defined by the declination at that point, the magnetic latitude by the inclination—the tangent of the magnetic latitude being half the tangent of the inclination—while the geomagnetic meridian is the portion of the great circle joining the point to the pole of the first‐degree harmonics and the geomagnetic latitude is the complement of the angular distance along that circle to the pole.
Characteristics of the upper region of the ionosphere
Authors: Berkner L. V. , Wells H. W. , Seaton S. L. 
Published: February 2008

Operation of stations making observations of the ionosphere in widely separated locations over the Earth's surface by the Department of Terrestrial Magnetism, Carnegie Institution of Washington, has produced data of unusual interest. Values of critical frequency of penetration and minimum virtual‐height for theF2‐region are now available from Washington, D.C., U.S.A., Huancayo, Peru, and Watheroo, Western Australia, for periods ranging from one to six years. These data are presented in the form of monthly averages of noon values. It is shown that noon values are a measure of conditions during the daytime hours. The average noon values of critical frequency for theF2‐region are found to have similar characteristics in both hemispheres, reaching a maximum from about November to February and a minimum from about May to August, at stations in both the Northern and Southern hemispheres simultaneously. This leads to a strong presumption that this variation is, predominantly, an annual effect. The simple hypothesis of thermal expansion of the upper atmosphere, which has been evolved by other investigators to account for the effects observed in the Northern Hemisphere alone, will not explain these critical‐frequency phenomena, observed in both hemispheres simultaneously. In this respect, therefore, it must be radically revised or discarded.Average minimum virtual‐heights of this region observed at noon show that at Washington and at Watheroo these heights change inversely with the noon zenith‐angle of the Sun, while at Huancayo, they change directly with the noon zenith‐angle. This reversal in character in equatorial regions is considered. It is possible that these effects may be explained by a new hypothesis of thermal movement of the upper atmosphere, considering the forces imposed upon the motions of the ions in the Earth's magnetic field.
New results of cosmic‐ray research
Authors: Hess V. F. 
Published: February 2008

Continuous registrations of the cosmic‐ray ionization by Steinke's standard apparatus at elevations above sea‐level of 2300 and 600 meters (Hafelekar and Innsbruck) kept at constant temperature from 1931 to 1934 and in 1936 have brought interesting results. Among these, for instance, the existence of a regular, small diurnal variation according to solar time has been established1.Recently one of my collaborators, W. Illing,2 tested the existence of diurnal variation according to sidereal time as postulated by A. H. Compton's theory of the extra‐galactic origin of the cosmic radiation. The curve derived from 21,000 hourly observations in three years showed a certain resemblance to Compton's theoretical curve, which however disappeared when all observations were reduced to the same outdoor temperature.
Interference with telegraph service during latter part of January 1938, caused by magnetic storm
Authors: Willever J. C. 
Published: February 2008

The following report from the Traffic Department of the Western Union Telegraph Company gives information on the severity and extent of interference with service during the latter part of January caused by the magnetic storm associated with Aurora Borealis:“While there was some interference noted on the circuits up and down the Pacific Coast, the maximum interference occurred elsewhere throughout the country, the transcontinental circuits being most seriously affected. The disturbance started on January 22, at which time the interference was comparatively slight, and gradually increased in intensity until the afternoon of the 25th, when maximum readings in excess of 400 volts were recorded in many parts of the country.
Magnetization of unmetamorphosed varves and marine sediments
Authors: McNish A. G. , Johnson E. A. 
Published: February 2008

Introduction—Knowledge concerning the range of its variation is essential to an understanding of the Earth's general magnetic field. Clearly, if, as some claim, the Earth's magnetic field has been completely reversed in past geologic ages our notions of its origin, and perhaps our entire conception of the Earth's interior, must be radically revised. On the other hand, if it can be shown that the Earth's general magnetic field is a rather static phenomenon and that the observed secular changes involve only a superficial portion of the field other types of causes are suggested.Direct observations of secular variation extend over four centuries at a few places on the surface of the Earth. Although some of the changes have been very large they suggest cyclic variations rather than continuous variations in one direction. Some of the more remarkable of these changes are a shift in declination from 11° east to over 24° west at London from 1600 to 1800, a decrease of 5900 gammas in horizontal intensity at Capetown from 1843 to the present time, and a decrease of 6000 gammas in vertical intensity off the Guinea Coast from 1885 to 1922. If changes as great as these have occurred in modern historic times how great have the changes been in thousands and millions of years of prehistory?
Blue auroral rays situated in the sunlit part of the atmosphere
Authors: Störmer Carl 
Published: February 2008

§ 1. The blue sunlit auroral rays on March 23, 1920—Since my permanent auroral stations in southern Norway were established in 1911, sunlit auroral rays have been observed and measured about 50 times, but among these, blue ones have occurred only on two occasions, the first March 23, 1920, and the second September 15, 1938, both before sunrise.A report on the blue rays of March 23, 1920, is given in a paper covering the period 1911‐1922.l From this paper we quote the following description:
Hermanus Magnetic Observatory, January to June, 1941
Authors: Ogg A. 
Published: February 2008

January 1—The period from 12h to 18h GMT was moderately disturbed.January 5–9—A storm began with a small commencement at 15h 45m GMT, January 5, with an increase of 11 gammas in H in four minutes. The storm continued until 0lh, January 7. There were further disturbances on January 7 in the period from 15h to 21h and on January 9 from 12h to 15h. The ranges of H we re of the order of 70 gammas.
Geomagnetic bays, their frequency and current‐systems
Authors: Silsbee H. C. , Vestine E. H. 
Published: February 2008

Birkeland [see 1 of “References” at end of paper] has made extensive studies of the field and current‐systems of bays, using data for magnetic stations of the Polar Year, 1882‐83, and less complete data for other years. In these important investigations he deduced considerable information respecting the geographical distribution of their fields and current‐systems. He suggested that the polar part of the current‐system in all probability flowed in (or beyond) the Earth's atmosphere with greatest concentration of current near the auroral zones at heights of 100‐700 km.Birkeland's supposition of an intake and outflow of current directly to or from the auroral zones has been shown to be somewhat doubtful and improbable as a consequence of later calculations of Vestine and Chapman [2]. His findings, however, in the main have been confirmed, although notably extended and to some degree reshaped in later valuable discussions by Steiner [3], Wiechert [4], McNish [5], Chapman and Bartels [6] and Hatakeyama [7].
Association of large ions and fog
Authors: Phillips Marcella Lindeman 
Published: February 2008

During the course of another investigation in which large ions were being measured by means of the large ion‐counter of the Department of Terrestrial Magnetism [see 1 under “References” at the end of paper] an abnormally high large‐ion count was noted during the night of December 3–4, 1941. The sudden rise in count preceded a widespread fog along the North Atlantic Coast, reported as being the worst in the past five years.Comparison of the ion‐count record with the record of visibility observed at Boiling Field (Table 1) showed that the concentration of large ions had risen to an unusually large value about seven hours before the fog set in, decreased during the fog, and increased to a large value again after the disappearance of the fog. Another dense fog formed during the next day but, unfortunately, no ion‐measurements were made at this time.