bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three‐hour‐range indices, K, of geomagnetic activity at the magnetic observatory, Hermanus, comparison with K‐indices at American‐operated observatories, and mean K‐indices, KA, for the years 1941–44
Authors: Ogg A. 
Published: February 2008

At the Washington Meeting of the International Association of Terrestrial Magnetism and Atmospheric Electricity in September, 1939, it was decided to adopt a new international measure of magnetic activity to meet requests for more detailed information than the daily magnetic‐character figure. It was decided to invite the cooperation of magnetic observatories in a three‐year period (1940–42) trial‐scheme of a three‐hour‐range index to replace the numerical‐character figure.The so‐called “Potsdamer erdmagnetische Kennziffer,” which was introduced for Potsdam in 1938 served as a model for what is called the index K. To start this trial‐scheme an important paper on the definition of K and on the fixing of K‐scales for the various observatories taking part in the scheme was published in this Journal [44, 411–454 (1939)] and also by the same authors a paper on the main features of daily magnetic activity at the observatories Sitka (Si), Cheltenham (Ch), Tucson (Tu), San Juan (SJ), Honolulu (Ho), Huancayo (Hu)7 and Watheroo (Wa) for the years 1938–39 [Terr. Mag., 45, 309–337 (1940)].
Geomagnetic storm at Elisabethville, March 28, 1946
Authors: Scott W. E. 
Published: February 2008

Dr. G. Heinrichs, Director of the Elisabethville Magnetic Observatory, Elisabethville, Katanga, Belgian Congo, reported the geomagnetic storm of March 28–29, 1946, as one of the “strongest” storms ever recorded there, approximating in severity and range that of March 1, 1941.Figure 1 shows the record of the magnetic storm at the Elisabethville Magnetic Observatory. The beginning of the storm—between 06h and 07h—was lost because the reserve recording‐spot was being adjusted at the time. Detailed accounts of the associated geomagnetic disturbance at individual observatories appear elsewhere in this issue of the Journal. However, several aspects merit some comment.
Cheltenham Magnetic Observatory July to September, 1946
Authors: Wiles William E. 
Published: February 2008

(Latitude 38° 44′.0 N., longitude 76° 50′.5 or 5h 07m3 W. of Gr.)July 18–19—Following a very slight disturbance in D and H, a mild magnetic storm began with a sudden commencement in all three elements at 09h 04m GMT, July 18, and persisted until about 15h, July 19. The first half of the storm consisted of rapid pulsations of small amplitude in both H and D. The character of the disturbance gradually changed to irregular oscillations of moderate amplitude, the change occurring in D at about 22h, July 18, and in H at about 02h, July 19. The Z‐trace did not exhibit serious disturbance at any time. Two K‐indices of 5 and six of 4 were recorded.
Tucson Magnetic Observatory July to September, 1946
Authors: Westerman C. Edward 
Published: February 2008

(Latitude 32° 14′.8 N., longitude 110° 50′.1 or 7h 23m3 W. of Gr.)July 7–8—A moderate storm of only about twenty‐four hours' duration began at 03h GMT, July 7. Most of the activity occurred during the first half of the period and was characterized by moderate, fairly long‐period changes in H. Little activity was noted in D and Z. Range in H: 163 gammas.
American magnetic character‐figure, CA, three‐hour‐range indices, K, and mean K‐indices, KA, for October to December, 1946, and summary for year 1946
Authors: Scott W. E. 
Published: February 2008

Summaries of American URSI broadcasts have appeared regularly in this Journal since the issue for December, 1930.As set forth in this Journal for June, 1937, “The Department of Terrestrial Magnetism and the United States Coast and Geodetic Survey with the cooperation of the United States Army and the United States Navy communication‐services and several amateur radio stations have undertaken to supply the American character‐figure based upon the reports of the seven American‐operated observatories—those of the Department of Terrestrial Magnetism at Huancayo in Peru and at Watheroo in Western Australia, and those of the United States Coast and Geodetic Survey at Cheltenham (Maryland), Honolulu (Hawaii), San Juan (Puerto Rico), Sitka (Alaska), and Tucson (Arizona).“ This character‐figure is being designated CA, and its values for the first twelve, the second twelve, and all twenty‐four hours of each Greenwich day for October to December, 1946, are given in Table 1.
Geophysical work of the National Geological Survey of China and of the Institute of Physics of the National Academy of Peiping of China
Authors: Wong Wen‐Hao 
Published: February 2008

(I) Academic research(A) Seismological observation—The Chiufeng Seismological Observatory was founded in 1929. It had a complete set of Wiechert seismographs for recording earthquakes of east Asia, and a complete set of the newest type of Galitzin seismographs for recording the remotest quakes. Observation work was headed by Dr. S. P. Lee since the very beginning. A monthly bulletin was published which provided valuable data for many foreign seismological stations. During 1929 to 1937 more than 2300 earthquakes were recorded, 500 of which can be used for the study of subcrustal conditions of the Earth. When Peiping fell to the Japanese in the summer of 1937, the Observatory was lost and observational work suspended.
Alibag Magnetic Observatory October to December, 1946
Authors: Rao M. P. 
Published: February 2008

(Latitude 18° 38′ N., longitude 72° 58′ E. or 4h 51m.5 E. of Gr.)November 5–6—A moderate disturbance commenced suddenly at 09h 22m, GMT, November 5, and continued till about 17h 30m, November 6. All the three elements recorded moderate fluctuations. The highest K‐index attained during the period was 5.
A nomograph for conversion of Fourier coefficients occurring in geomagnetic computations
Authors: Schneider Otto 
Published: February 2008

Whenever a numerical operation of standard type is to be repeated a great number of times, as often occurs with geomagnetic material of statistical character, the use of nomographs may prove convenient, since it represents a considerable saving of time, provided that the amount of work is large enough to compensate the time of preparing and drawing the nomograph. In the present note, attention is drawn to the practical advantages of this method, widely used in other branches of geophysics and in engineering.A very simple example is given by the following case, referring to an analysis of S and L at Batavia. In the course of that investigation, a great number of pairs of harmonic coefficients representing diurnal and semidiurnal variations on individual days had to be transformed in amplitude and phase due to a change, in 1920, of the tabulating scheme adopted by that observatory. Starting with January 1, 1920, hourly mean values according to standard time (105° meridian) were published instead of instantaneous values for local mean time. Therefore, the harmonic coefficients for days after January 1, 1920, must be reduced in the following way:
Some early signal‐intensity measurements
Authors: Seaton S. L. 
Published: February 2008

Eighteen years ago the Department of Terrestrial Magnetism of the Carnegie Institution of Washington, collected radio wave‐propagation data throughout the world during Cruise VII of the research Yacht Carnegie. In 1930 the log‐books of the yacht were examined for high‐frequency radio‐propagation data which were abstracted and summarized.One of the studies undertaken by means of these data was a collection of radio signal‐strengths over long distances in terms of local time at the midpoint of the path of propagation. The reasoning which led to the reference‐time of this path's midpoint was prompted by the fact that the signal‐strength data were collected on a moving observatory. Since the yacht cruised in all oceans and made measurements of signals arriving from all directions, it appeared natural to choose a time‐scale upon which it was possible to represent the information in such a way that any portion of it could be compared with any other part. There resulted a graph of Figure 1.
Eclipse expedition to study ionosphere
Authors: Grosvenor Gilbert 
Published: February 2008

What happens to the nebulous ionosphere, the all‐important radio‐reflecting layer high above the Earth, when the Moon's shadow “punches a hole” in it during an eclipse of the Sun? This will be investigated on May 20, 1947, by the Army Air Forces‐National Geographic Society Eclipse Expedition at Bocayuva, Brazil. Because the ionosphere is created by ultraviolet radiation from the Sun, which makes air‐molecules in the upper atmosphere electrically conducting, scientists are interested in knowing what happens to the ionosphere when this radiation is cut off suddenly during an eclipse.Study of the ionosphere is important because of the increasing use of long‐distance communication by radio. High‐frequency radio signals travel around the Earth in a series of giant bounces between the ground and the reflecting layers of the ionosphere, which range from about 50 to 250 miles in altitude. When these layers disappear or are disrupted, long‐distance communication by radio fails or is garbled.
Alibag Magnetic Observatory January to March, 1947
Authors: Rao M. P. 
Published: February 2008

(Latitude 18° 38′.3 N., longitude 72° 52′.3 or 4h 51m.5 E. of Gr.)January 16–17—A sudden‐commencement disturbance began at 03h 27m GMT, January 16, and continued until about 01h, January 17. The initial stage of the disturbance was characterized by small fluctuations in all the three elements. One K‐index of 6 and one of 5 were recorded during the disturbance. Ranges: D, 5′.8; H, 153 gammas; Z, 58 gammas.
Apia Observatory April to September, 1947
Authors: Beagley J. W. 
Published: February 2008

(Latitude 13° 48′.4 S., longitude 171° 46′.5 or 11h 27m.1 W. of Gr.)April 8–10—A marked sudden commencement at 21h 51m GMT, April 8, was followed by mild irregular movement with a gradual return to normal at 09h, April 10. K‐indices of 5 were recorded during the last three‐hour period of April 8 and the second of April 9.
Sitka Magnetic Observatory October to December, 1947
Authors: Campbell Joel B. 
Published: February 2008

(Latitude 57° 03′.0 N., longitude 135° 20′.1 or 9h 01m.3 W. of Gr.)September 30‐October 3—The magnetic disturbance which was reported in the last quarterly report as beginning suddenly at 18h 08m GMT, September 30, continued only moderately disturbed until 03h, October 2. However, after that time there was a sharp increase in storminess and for the following sixteen hours or until 19h, October 2, there occurred rather severe activity in the form of short‐period oscillations of varying amplitudes, superposed on small bays. Three K‐indices of 7 and three of 6 were recorded during this period. After a short lull‐period there was another increase in storminess and between 03h and 10h, October 3, three K‐indices of 7 were recorded. The storm began to die out at about 12h, October 3, and may be said to have ended three hours later.
A Panoramic Ionospheric Echo Recorder
Authors: Stoffregen W. 
Published: February 2008

In the following is described an automatic radio echo transmitter‐receiver in which the panoramic principle commonly used in radar is employed with some modifications. By means of the oscillograph arrangements connected to the receiver one thus obtains a standing picture of the reflections from the ionospheric layers on the screen of a large cathode‐ray tube with long afterglow. By this method of recording it is therefore possible to study rapid changes in the degree of ionisation of the various layers, and sporadic layers of short life‐time may he detected anti studied.The Panoramic Ionospheric Echo Recorder is of especial interest where a study of ionospheric problems in connection with magnetic disturbances and aurora at places in high latitude is contemplated, and recorders of this type will be placed at several stations in Norway for the purpose of carrying out such investigations. The recorder is also intended to be used at some of the important short‐wave receiving stations, which are interested in at any time obtaining a survey of the ionospheric conditions.
Sitka Magnetic Observatory April to June, 1948
Authors: Campbell Joel B. 
Published: February 2008

(Latitude 57° 03′.0 N., longitude 135° 20′.1 or 9h 01m.3 W. of Gr.)April 22—A moderate disturbance of short duration began gradually at about 00h GMT, April 22, and continued until about 18h of the same date. The most disturbed portion occurred between 12h and 13h, when there was violent activity in the form of short‐period, large‐amplitude oscillations. A K‐index of 8 resulted from this activity.
Tucson Magnetic Observatory April to June, 1948
Authors: Nelson J. H. 
Published: February 2008

(Latitude 32° 14′.8 N., longitude 110° 50′.1 or 7h 23m.3 W. of Gr.)April 6–7—At 03h 57m GMT, April 6, there was a momentary depression of about 2 gammas in H, followed immediately by a rapid 36‐gamma increase to mark the sudden commencement of a moderate storm. Simultaneously with the changes in H, smaller disturbances began in D and Z. During the first thirteen hours the storm activity was very mild, with small ranges. Intensity of the disturbance increased a little just before 17h, with pronounced short‐period moderate‐amplitude variations in D and H. A square bay in H was recorded between 18.2h and 19.7h. Activity continued, decreasing slightly in intensity until the end of the storm about the middle of the Greenwich day, April 7. Range in H was 97 gammas.
On the concentration of condensation nuclei in the air over the North Atlantic
Authors: Hess Victor F. 
Published: February 2008

On account of the scarcity of data on the number of nuclei over the oceans, I thought it would be interesting to carry out new measurements of the nucleus content of the air during a voyage from New York to Le Havre, France, and back, aboard the SS America of the United States Lines. The last observations in the North Atlantic were made between 1928 and 1934. It seemed also worth while to see if the contamination of the atmosphere had increased since that time.The instrument used was an Aitken pocket dust counter (modified model, after G. Luedeling), which was recalibrated according to the findings of V. F. Hess and C. O'Brolchain [see 1 of "References" at end of paper].
Changes in ionization and radio reception during the sunspot‐period 1944–1947
Authors: Stetson Harlan T. 
Published: February 2008

If 12‐month running means of critical frequencies are taken to eliminate seasonal effects, a close correspondence exists between critical frequencies for both the E‐ and F‐layers and sunspots. Since the ultra‐violet light of the Sun is assumed to be the major ionizing agent, this increase in ionization with sunspots during the night hours presents some interesting cosmic problems as to the cause and the maintenance of ionization on the unilluminated half of the Earth.Standardized measurements of field intensities of the Bureau of Standards standard‐frequency signal, WWV, have been recorded at the Cosmic Terrestrial Research Laboratory at Needham during recent years for the 5‐, 10‐, and 15‐Mc frequencies. Curves of night fields of WWV‐5‐Mc show that during the rise of sunspots from 1945 to 1947 the average values recorded between 22h and 02h rose from 300 microvolts to 900 microvolts when the Zurich sunspot‐nurnber of 105 was reached; thereafter, field intensities decreased in value as sunspot‐numbers continued to rise to a maximum of 150, a value reached last year. The decline in field strength with very high sunspot‐numbers is attributed to attenuation introduced by increase ionization of the lower layers. Day fields, representing averages of observations between 10h and 14h showed a steady decline with increasing sunspots, a fact which is again explained on the basis of increasing absorption in the lower layers. The changes in the daytime field were from 225 microvolts when the sunspot‐number was 20 to about 15 microvolts when sunspot‐numbers were 150.For the 10‐Mc reception day fields rose from a value slightly in excess of 90 microvolts, when the sunspot‐number was 80, to values of 260 microvolts or more, when sunspot‐numbers registered from 140 to 150. Night fields on the 10‐Mc frequency, based on observations between 22h and 02h, rose from 10 microvolts, with sunspot‐number of 80, to values in excess of 30. microvolts, with sunspot‐numbers between 140 and 150.Observations on the broadcast band of Station WBBM, Chicago, 780 kc, received at Needham, a distance of 851 miles, show a general decline in field intensities from values in excess of 270 microvolts to values of but 45 microvolts as sunspot‐numbers increased from 20 to a maximum value of 150.
Committee on characterization of magnetic disturbances, International Association of Terrestrial Magnetism and Electricity
Authors: Bartels Julius 
Published: February 2008

(1) Dr. J. Veldkamp, De Bilt, has notified the President of our Association, Professor S. Chapman, Oxford, that the collection, reduction, and printing of character‐figures and three‐hour‐range indices can be taken up, from January 1, 1949, at the Kon. Nederlandsch Meteorologisch Instituut under the same conditions as before, namely, that the cost of printing and shipping the publications is paid by the Association. He feels certain that the sum of $2,000 set aside for the next three years will be sufficient.(2) When, at the Oslo Meeting, it was not certain whether De Bilt was in the position to serve as Dr. van Dijk had done for so many years, Professor Lahay had kindly volunteered to establish the (C + K)‐center at Uccle. The President has informed Professor Lahay of De Bilt's definite offer; in reply, Professor Lahay said that he considered it as a matter of course that the (C + K)‐center should be at De Bilt.
Geophysical Institute of Huancayo April to September, 1948
Authors: Giesecke Albert A. 
Published: February 2008

(Latitude 12° 02′.7 N., longitude 76° 20′.4 or 5h 01m.4 W. of Gr.)April 6—A sudden‐commencement type of storm was recorded at 03h 59m GMT, April 6, with a rapid increase in H of about 36 gammas, an increase in Z, and a slight decrease in D. This sudden change was followed by relative tranquility until 16h 53m, when all elements showed pronounced activity. H increased about 122 gammas and was followed by rapid oscillations of an amplitude averaging about 40 gammas, reaching a peak‐value at 18h 02m of 325 gammas above the base‐line, and thence rapidly decreasing to a minimum at 18h 22m, 170 gammas below the base‐line. The vertical component Z also increased sharply some 15 gammas at 16h 53m, while D was likewise increasing almost 3′.
Hermanus Magnetic Observatory July to September, 1948
Authors: van Wijk A. M. 
Published: February 2008

(Latitude 34° 25′.2 S., longitude 19° 13′.5 or 1h 16m.9 E. of Gr.)July 26—A small crochet appeared on the traces at 08h 38m GMT, July 26. Minor disturbances were recorded during the ensuing six days.
Die Verteilung des erdmagnetischen Potentials in Bezug auf beliebige Durchmesser der Erde
Authors: Schmidt Ad. 
Published: February 2008

In einem vor drei Jahren gehaltenen, im verflossenen Frühjahre veröffentlichten Vortrage1 hat Herr von Bezold darauf aufmerksam gemacht, dass die Mittelwerte, die das magnetische Potential auf den einzelnen Parallelkreisen annimmt, mit sehr grosser Annäherung dem Sinus der geographishen Breite β, anders ausgedrückt dem Cosinus des Nordpolabstandes u proportional verlaufen. Indem er nämlich die Gesamtheit dieser Mittelwerte, das von ihm sogenannte normale Potential, mit Vn, die Abweichungen von diesem mit Van bezeichnet, so dass das ganze Potential V durch die GleichungV = Vn + Vabestimmt wird, findet er, dass mit R als dem Erdradius fastVn: R = K sin βzu setzen ist. Auf der Grundlage der von Quintus Icilius gezeichneten Karte des Potentials für die Epoche 1880,o ergiebt sich ihm K gleich 0,330 cm−½ g−½ s−1, während die mittlere Abweichung der Function K sin β von Vn : R nicht grosser als ± 0,0029 cm−½ g½s−1 wird.Es liegt die Frage nahe, ob die Rotationsaxe der Erde in dieser Hinsicht vor ihren übrigen Durchmessern ausgezeichnet ist oder ob etwa bei einem unter diesen die entsprechend gebildeten Abweichungen noch geringer ausfallen. Mit Rücksicht auf die verschiedentlich, vor allem auch in der genannten Abhandlung bemerkte Möglichkeit eines Zusammenhangs der erdmagnetischen Erscheinungen mit der Rotation der Erde kann eine exacte Beantwortung dieser Frage, gleichgültig, in welchem Sinne sie auch ausfallen mag, einiges Interesse beanspruchen.
A summary of the results of the recent magnetic survey of Great Britain and Ireland conducted by professors Rücker and Thorpe: Part III. On the relation between the magnetic and the geological constitution of Great Britain and Ireland
Authors: Rücker A. W. 
Published: February 2008

In the memoir of which this paper is a brief summary we have carefully distinguished between the problem of determining the positions of the loci and centers of magnetic disturbances, and that of explaining the means by which the Disturbing Forces are produced. On the latter point there may be some difference of opinion.The most probable causes of the Forces are electrical Earth currents and magnetic rocks, or both of these combined. It may be desirable to give an outline of the evidence which leads me to believe that the presence of magnetic rocks is the more potent of these sources of disturbance.
Sur l'inclinaison de l'aiguille aimantée à l'époque étrusqu
Authors: Carlheim‐Gyllensköld V. 
Published: February 2008

Les premières observations directes de l'inclinaison de l'aiguille aimantée datent de la fin du XVIe siècle; des informations antérieures pouvaient être tirées de la position du point de convergence des rayons de l'aurore boréale, si cet élément avait été observé au moyen‐âge.Dernièrement M. Folgheraiter a publié sur le même sujet plusieurs notes intéressantes, dont M. Chistoni a fait une analyse dans le numéro 2, tome II, de ce journal. En se reportant à l'aimantation conservée par certains objets d'argile cuite, l'Auteur est arrivé à ce résultat, que l'inclinaison en Italie à l'époque étrusque, au VIIIe et VIe siècles avant notre ère, a été nulle ou même négative.
Le nouveau pavillon magnétique de l'observatoire du Parc Saint‐Maur
Authors: Moureaux Th. 
Published: February 2008

L'observatoire du Parc Saint‐Maur est une dépendance du Bureau central météorologique de France; il est situé au voisinage de la Marne, à 12 kilomètres E. SE. de l'observatoire de Paris, et à 7 kilomètres des limites de la capitale. Ses coordonnées géographiques sont:Longitude, 0° 9′ 23″ E. de Paris.Latitude, 48 48 34 N.La propriété, en grande partie boisée, a une superficie de trios hectares; des rues la bordent sur ses quatre côtés.
A Comparison of Energy Balance Methods for Estimating Atmospheric Thermal Radiation
Authors: Cooley Keith R. , Idso Sherwood B. 
Published: February 2008

A radiation balance method and a modified radiation balance method were used to determine hourly and daily values of atmospheric thermal radiation on three clear and three cloudy days during February and March 1970 at Phoenix, Arizona. The radiation balance was used over surfaces of bare soil, Bermuda grass, and open water; whereas the modified radiation balance was used over the open water surface only. The modified radiation balance differed from the pure radiation balance method in that net radiation was calculated as the residual in the energy equation rather than measured.The values of atmospheric thermal radiation thus obtained were compared to valuesobtained from measurements of incoming, all‐wave radiation minus incoming solar radiation.From this analysis it appeared that the best alternative to the semi‐direct measurementof atmospheric thermal radiation was the radiation balance over the bare soil surface.Results from this method were of sufficient accuracy, even on an hourly basis, for mostresearch studies, and were even better on a daily basis. Radiation balances over grass andwater surfaces were somewhat less satisfactory, but still better than the modified radiationbalance method.