bluuebunny/crossref_metadata_2025_split huggingface dataset:
Annual variation of the critical frequencies of the ionized layers at Tromsö during 1938
Authors: Harang Leiv 
Published: February 2008

In previous notes the monthly means of the critical frequencies of the ionized layers for preceding years have been given. Regular observations were usually taken on six days during the week at 10h, 12h, and 14h local time. At Tromsö, situated near the auroral zone, the conditions of the ionosphere are strongly influenced by magnetic storms and the echoes are often lacking during disturbed periods, or more or less irregular and scattered echoes appear which sometimes make a precise critical‐frequency determination difficult.Figure 1 shows the annual variation of the noon‐values of the critical frequencies for the ., , and E‐layers.
The magnetic character of the year 1938, review of the years 1928–1938, and numerical magnetic character of days 1938
Authors: van Dijk G. 
Published: February 2008

The annual review of the “Caractère magnétique de chaque jour” for 1938 has been drawn up in the same manner as for the preceding years 1, moreover it contains a review of the collaboration of the observatories during the years 1928 to 1938.In 1938, sixty–one observatories contributed to the quarterly tables; 46 of them sent complete data.
Provisional solar and magnetic character‐figures, Mount Wilson Observatory April to September, 1939
Authors: Mulders Elizabeth Sternberg , Nicholson Seth B. 
Published: February 2008

The storm of April 17 began 24 hours after a large active sunspot‐group had crossed the central meridian in latitude north 13°. The group first appeared on April 12 and developed rapidly in size. A red auroral display was seen on Mount Wilson on April 17 while this storm was in progress.A bright chromospheric eruption of intensity 3 began at 16h 47m GMT, April 21, in a spot‐group north 28°, east 60°. Starting at 16h 54m, H decreased 39 gammas in 21 minutes. The time of its recovery is uncertain because of a slight disturbance which lasted throughout the day. A very well‐marked radio fade‐out was observed at the Huancayo Magnetic Observatory, beginning at 16h 54m, with a complete fade‐out from 16h 56m to 17h 49m.
American URSI broadcasts of cosmic data, with american magnetic character‐figure CA July to September, 1939
Authors: Johnston H. F. 
Published: February 2008

The data for terrestrial magnetism, sunspots, and solar constant are the same as given in previous tables.The first three columns of Table 1 give (1) the magnetic character according to the scale 0–2 of the International Commission of Terrestrial Magnetism and Atmospheric Electricity, (2) the type featuring the day other than normal by the letters b, p, o, and i for days marked by bay, rapid pulsations, long‐period oscillations, and irregular oscillations, respectively, and (3) the hour and minute of Greenwich mean time marking the beginning of a storm, the end of the storm being indicated in the foot‐note to the Table.
Cheltenham Magnetic Observatory October to December, 1939
Authors: Ludy Albert K. 
Published: February 2008

October 3–4—A mild disturbance began gradually about 07 h GMT, October 3. It reached its peak between 02 h and 06 h, October 4, during which interval all three elements had their greatest ranges. Ranges: D, 63′; H, 211 gammas; Z, 203 gammas.October 6—An interval of moderate activity occurred between 05 h and 11 h GMT, October 6. Ranges: D, 22′; H, 123 gammas; Z, 126 gammas.
The local variation of atmospheric potential‐gradient measured at Taihoku, Formosa, Japan
Authors: Ogasahara K. 
Published: February 2008

In spite of the importance of the study of atmospheric electricity in tropical regions, there are practically few data of observations and many problems remaining still unsolved.Formosa is an island extending over the north temperate and the tropical zones, and under both continental and marine meteorological influences it shows a special feature in weather‐type, for example, the Island is very often made the battle‐field of a polar continental airmass (Siberian) and a tropical marine air‐mass (Pacific Ocean) coming into collision to give rise to a great disturbance in the atmospheric‐ electric field there.
Report on work in terrestrial magnetism and electricity in U.S.S.R. during 1936–1939
Authors: Lazarev P. P. , Leuschin N. I. , Nikolsky N. N. , Pushkov N. V. , Trubyatchinsky N. N. 
Published: February 2008

(I) Observatories and institutions—The work in terrestrial magnetism and electricity is done at many observatories and institutions. The fields covered by the principal ones are as follows:(1) Institute of Theoretical Geophysics of the Academy of Sciences of U.S.S.R., Moscow—Investigational and experimental work in magnetism of rocks and ionosphere
American URSI broadcasts of cosmic data, with American magnetic character‐figure CA, October to December, 1939, and summary of CA for year 1939
Authors: Johnston H. F. 
Published: February 2008

The data for terrestrial magnetism, sunspots, and solar constant are the same as given in previous tables.The three columns for each month in Table 1 give (1) the magnetic character according to the scale 0–2 of the International Commission of Terrestrial Magnetism and Atmospheric Electricity, (2) the type featuring the day other than normal by the letters b, p, o, and i for days marked by bay, rapid pulsations, long‐period oscillations, and irregular oscillations, respectively, and (3) the hour and minute of Greenwich mean time marking the beginning of a storm, the end of the storm being indicated in the foot‐note to the Table.
Alibag Magnetic Observatory October to December, 1939
Authors: Rangaswami M. R. 
Published: February 2008

(Latitude 18° 38′.3 N., longitude 72° 52′.3 or 4h 51m.5 E. of Gr.)October 3–4—A moderate disturbance began at 09h 00m GMT, October 3, with a sudden commencement which was not large. H attained its minimum value at 19h 16m, October 3. The disturbance ended at about 05h.5, October 4. Ranges: D, 4.′1; H, 168 gammas; Z, 27 gammas.
Geomagnetic tides in horizontal intensity at Huancayo
Authors: Bartels J. , Johnston H. F. 
Published: February 2008

Following an introductory survey of the main features of the solar and lunar daily variations, S and L, in horizontal intensity, H, in January at Huancayo, days with conspicuous lunar influences, geomagnetic tides, are discussed. A separation of S and L on such “big‐L‐days” is attempted. Daily ranges A in H are then introduced for the study of the intensity of S and, thereby, of the solar wave‐radiation W. Up to international character‐figures C=1.1, A is found independent of changes in the solar corpuscular radiation P.Various methods for studying L are compared. Lunar semimonthly waves in the ranges A are computed and discussed in their change with season and sunspot‐cycle. In the months November to March, when L is larger than in the rest of the year, L and S increase, in their effects on A, proportionally to each other from sunspot‐minimum to sunspot‐maximum, but around June, when L is small, it does not participate in the change of S with the sunspot‐cycle. The day‐to‐day variability of S and L is studied in some detail; S and L fluctuate rather independently of each other, and the relative fluctuations of L seem to be greater than those of S. The elimination of the lunar effect AL is described; (A − AL) = As is proposed as a measure for W.A more extensive summary, including some results to be described in Part II, has been published elsewhere [see 4 of “References” at end of paper].
Final Relative Sunspot‐Numbers for 1940
Authors: Brunner W. 
Published: February 2008

Table 1 contains the final sunspot‐numbers for 1940, for the whole disk of the Sun, based on observations made at the Zürich Observatory, supplemented by series furnished by other cooperating observatories for days (indicated by asterisks) on which no observations were possible at Zürich.Table 2 gives the yearly means of the relative numbers, R, since the last minimum 1933 and the number of days without spots.
Ionospheric Recordings During Magnetic Storm of March 1, 1941
Authors: Wells H. W. 
Published: February 2008

Examination of automatic multifrequency ionospheric records obtained at the Kensington Experimental Station of the Department of Terrestrial Magnetism, Carnegie Institution of Washington, during the intense magnetic storm of March 1, 1941, reveals that the ionized regions of the Earth's outer atmosphere were greatly disturbed, and that the period of greatest disturbance corresponds to that of greatest magnetic activity.Commencement of the ionospheric disturbance was associated with the development of an ionized region between the normal levels of the E‐ and F‐regions. Virtual height of this region was 160 km at 06h 15m GMT. By 06h 30m its maximum ion‐density had increased threefold and its virtual height had fallen to normal E‐region levels at 130 km. Radio reflections from this region were returned by the normal process of magnetoionic double refraction. Both ordinary and extraordinary wave‐components were recorded, and reflection‐coefficients were not high. Apparently the condition was not one of simple sporadic E‐region ionization.
Cheltenham Magnetic Observatory, January to March, 1941
Authors: Ludy Albert K. 
Published: February 2008

January 16–21—On January 16 at 20h 30m GMT, a disturbance of mild proportions began and continued until the end of January 21. The greatest, K‐number during this interval was 5 which occurred eight times in the five days.January 23–28—The field again became disturbed on January 23 and continued so until January 28. During this time there were three K‐numbers as great as 5.
Solar and magnetic data, April to June, 1942, Mount Wilson Observatory
Authors: Nicholson Seth B. , Mulders Elizabeth Sternberg 
Published: February 2008

No magnetic storms were recorded at Mount Wilson in April, May, or June, 1942.Sunspot‐group No. 7397, with which magnetic storms had been associated in February and March, was last seen at the west limb of the Sun on April 3. Small disturbances in the Earth's magnetic field on April 1‐4 may have resulted from activity associated with this group.
Sudden‐commencement magnetic storms in 1941
Authors: Ogg A. 
Published: February 2008

As a comparison of the sudden‐commencement storms reported in the JOURNAL proved of interest, the times of commencement were assembled as in Table 1. The times are Greenwich mean time. Only storms, which are stated in the reports to be sudden‐commencement storms, are quoted.At Hermanus Observatory the time is recorded on the magnetograms by a very accurate Synchronome slave clock.
Solar and Magnetic Data, January to March, 1943, Mount Wilson Observatory
Authors: Nicholson Seth B. , Mulders Elizabeth Sternberg 
Published: February 2008

No magnetic storms were recorded in the first quarter of the year 1943. Two magnetic disturbances occurred, however, in which the horizontal component decreased by more than 100 gammas. The first began at about 19h GMT, January 20, the second about 16h GMT, March 29.Three large sunspot‐groups were observed: Mount Wilson No. 7550, which crossed the central meridian on February 11.7; No. 7555, on February 25.7; and No. 7559, on March 10.6. These groups, although large, were only moderately active; they were not accompanied by significant geomagnetic activity.
Tucson Magnetic Observatory, January to March, 1943
Authors: Nelson J. H. 
Published: February 2008

(Latitude 32° 14′.8 N., longitude 110° 50′.1 or 7h 23m.4 W. of Gr.)January 4–5—A very mild storm began about 10h GMT, January 4, and continued for approximately twenty‐four hours. The principal characteristic seemed to be irregular oscillations of moderately short period of D and H. Ranges: D, 11′; H, 76 gammas.
Apia Magnetic Observatory, January to March, 1943
Authors: Sapsford H. Bruce 
Published: February 2008

(Latitude 13° 48′.4 S., longitude 171° 46′.5 or 11h 27m.1 W. of Gr.)January 4–5—At 10h GMT, January 4, an emergent disturbance commenced and lasted until 17h. The trace remained slightly disturbed until 10h, January 5.
SITKA MAGNETIC OBSERVATORY JULY TO SEPTEMBER, 1943
Authors: Pinckney Harold W. 
Published: February 2008

(Latitude 57° 03′.0 N., longitude 135° 20′.1 or 9h 01m.3 W. of Gr.)July 3—Gradually increasing deviations from normal preceded by half a day a briefly severe disturbance occurring between 04h and 09h GMT, July 3, during which was recorded a range of 730 gammas in H.
American Magnetic Character‐Figure, CA Three‐Hour‐Range Indices, K, and Mean K‐Indices, KA, for October to December, 1943, and Summary for Year 1943
Authors: Johnston H. F. 
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, 1943, are given in Table 1.
Preliminary Magnetic Character‐Figures, C, for 1942 and Lists of Five Selected Quiet and Disturbed Days for January to June, 1943
Authors: Johnston H. F. 
Published: February 2008

Reports of magnetic character on a scale of 0, 1, and 2 have now been received from a total of 43 observatories for the year 1942. The preliminary International Character‐Figures, C, for 1942 are given in Table 1. These figures will closely approximate the final values that can be derived when characters are available from more magnetic observatories.Reports of geomagnetic activity for the first six months of 1943 have been received from a sufficient number of observatories so that the international quiet and disturbed days can be selected in accordance with the method outlined on pages 219–227 in the December 1943 issue of this JOURNAL. The selected days are shown in Table 2. The selection is based on the reports of magnetic character on a scale of 0, 1, 2 from 40 observatories and on the reports of K‐indices from 23 observatories.
The Geographic Incidence of Aurora and Magnetic Disturbance, Northern Hemisphere
Authors: Vestine E. H. 
Published: February 2008

Fritz [see 7 of “References” at end of paper] in a famous memoir published in 1881 discussed the frequency and characteristics of aurora observed in the Northern Hemisphere during the years 1700 to 1872. Using observations during this 172‐year period [8] he also constructed his well‐known map of isochasms of equal auroral frequency.Beginning is made here in the statistical analysis of the auroral data since accumulated, a task of considerable magnitude if undertaken with any pretense at completeness. The present paper is concerned mainly with the variation with geographic position of the average daily frequency of aurora in high latitudes, and of geomagnetic disturbance.
American Magnetic Character‐Figure, CA, Three‐Hour‐Range Indices, K, and Mean K‐Indices, KA, for January to March, 1944
Authors: Johnston H. F. 
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 Goast and Geodetic Survey at Cheltenham (Maryland), Honolulu (Hawaii), San Juan (Puerto Rico), Sitka (Alaska), and Tucson (Arizona).” The H‐variometer at Honolulu was not in operation during the period from March 12 to March 31. 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 January to March 1944, are given in Table 1.
Apia Observatory, January to March, 1944
Authors: Sapsford H. Bruce 
Published: February 2008

(Latitude 13° 48′.4 S., longitude 171° 46′.5 or 11h 27.1m W. of Gr.)February 13–14—H became disturbed at 23h 00m GMT, February 13. A maximum was reached at 00h 19m, February 14, and decreased steadily to a minimum at 07h 05m. After this the intensity increased with fluctuations to 14h 06m, when the trace became normal. D and Z were slightly disturbed. Range in H was 155 gammas.
Cheltenham Magnetic Observatory, July to September, 1944
Authors: Hershberger John 
Published: February 2008

(Latitude 38° 44′.0 N., longitude 76° 50′.5 or 5h 07m.4 W. of Gr.)August 2–3—A rather severe storm began, after some hours of minor activity, at about 21h GMT, August 2, and ended at about 12h, August 3. Throughout the storm, the longer‐period fluctuations predominated. The greatest activity occurred in declination, the total range of which was just over 1°. K‐indices of 7 were recorded for the first two three‐hour periods of August 3, and indices of 6 for the next two periods.
Watheroo Magnetic Observatory, July to September, 1944
Authors: Parkinson W. C. 
Published: February 2008

(Latitude 30° 19′.1 S., longitude 115° 52′.6 or 7h 43m.5 E. of Gr.)September 30—Between 13h and 16h GMT, September 30, there was a large bay and peak shown in all three elements. The first feature was most clearly shown in the H‐trace and H reached its minimum value at 14h 47m. Thereafter H quickly increased until it reached its maximum value at 15h 05m. A corresponding bay in the Z‐trace culminated at the same time, while the westerly declination reached a minimum value at 15h 04m. Ranges: D, 11′.2; H, 77 gammas; Z, 88 gammas.
Cheltenham Magnetic Observatory, October to December, 1944
Authors: Hershberger John 
Published: February 2008

(Latitude 38° 44′.0 N., longitude 76° 50′.5 or 5h 07m.4 W. of Gr.)October 10–11—A period of moderate activity beginning at about 19h 20m GMT, October 10, and ending at about 06h, October 11, included a rather deep bay in declination which resulted in a K‐index of 6 for the second three‐hour period of October 11.
Tucson Magnetic Observatory, October to December, 1944
Authors: Nelson J. H. 
Published: February 2008

(Latitude 32° 14′.8 N., longitude 110° 50′.1 or 7h 23m.3 W. of Gr.)October 10–11—A moderate storm began about 19h GMT, October 10, without sharp beginning. A prominent but irregular bay in H occurred between 00h and 06h, October 11, during which period D reached its eastward maximum. Following this there was only mild activity until a 3‐hour period beginning at 14h, during which moderate variations in D and H occurred; then there was again only mild disturbance until the end of the storm about 24h, October 11. Ranges: D, 15′.5; H, 123 gammas; Z, 36 gammas.
Huancayo Magnetic Observatory, October to December, 1944
Authors: Ledig Paul G. 
Published: February 2008

(Latitude 12° 02′.7 S., longitude 76° 20′.4 or 5h 01m.4 W. of Gr.)October 11—There was a short magnetic disturbance which began gradually at about 13h GMT, October 11, and was characterized by a rapid decrease in H between 15h 40m and 15h 50m, and with a very large decrease from 16h 10m to 16h 35m and a very low minimum at 16h 48m. The range was 295 gammas in a little over an hour. The disturbance died out rapidly after 17h and affected D and Z only mildly.
The Comparison of Horizontal‐Intensity Magnetometers
Authors: Ogg A. 
Published: February 2008

A paper on “The determination of the horizontal component of the Earth's magnetic force at the Magnetic Observatory, Hermanus” by A. Ogg, B. Gotsman, and A. M. van Wijk [see 1 of “References” at end of paper], which dealt mainly with the theory of the Adolf Schmidt standard magnetometer and a simplified method of using it, contained results of the comparison of different types of horizontal‐intensity magnetometers. Since these results were published further data are available for this comparison.The magnetometers, which were available for this comparison, were the three la Cour horizontal‐force magnetometers (QHM) 29, 30, and 58; CIW magnetometer 17; the Adolf Schmidt standard magnetometer; and the F. E. Smith coil‐magnetometer.
Solar and Magnetic Data, January to March, 1945, Mount Wilson Observatory
Authors: Nicholson Seth B. , Mulders Elizabeth Sternberg 
Published: February 2008

During the magnetic storm of January 15 no significant solar activity was observed. At the beginning of the storm of January 28, an active bipolar sunspot‐group of the old cycle, Mount Wilson No. 7719, latitude 7° south, which developed on the disk sometime between January 24 and 27, was 37° west of the central meridian.When the storm of March 11 began, a large group, No. 7729, latitude 14° south, was 2.1 days past the central meridian. A solar flare was observed near this group on March 10 from 16h 51m to 18h 43m GCT. When the storm of March 14 began, the group was near the west limb. Clouds prevented observations on March 13, 14, and 15.
Not on Magnetic Character‐Figures C for 1943
Authors: Swoboda G. 
Published: February 2008

Herewith (Table 1) are the daily international magnetic character‐figures C for 1943, established by Professor J. Bartels and essentially derived from the data of 16 observatories.Professor Bartels also selected as days of magnetic disturbance during 1943 for reproduction the following (hours given are in universal time, that is, GMT):
Tucson Magnetic Observatory July to September, 1945
Authors: Westerman C. Edward 
Published: February 2008

(Latitude 32° 14′.8 N., longitude 110° 50′.1 or 7h 23m.3 W. of Gr.)August 27–29—A moderate magnetic storm began at 20h GMT on August 27, with H gradually increasing for the first five hours while D remained more or less normal. During the next three hours, 01h‐4h on August 28, H plunged approximately 190 gammas while D fluctuated within a range of only 8′. H recovered partially for the next two hours and then gradually drifted back to normal while D remained fairly undisturbed until the end of the storm at 07h on August 29. Z was undisturbed throughout except for a slight gradual increase during which time H dropped 190 gammas.
Huancayo Magnetic Observatory July to September, 1945
Authors: Ledig Paul G. 
Published: February 2008

(Latitude 12° 02′.7 S., longitude 76° 20′.4 or 5h 01m.4 W. of Gr.)August 28—Although there were no real disturbances during August, there was an unusual, deep bay recorded in H on August 28. This occurred between 01h and 05h GMT and consisted entirely of a large and slow decrease to a point 153 gammas below the H base‐line and then a return to practically the normal position of the H‐trace. There was no disturbance following this bay, nor any marked changes in D or Z.