Journal of the Meteorological Society of Japan. Ser. II
Online ISSN : 2186-9057
Print ISSN : 0026-1165
ISSN-L : 0026-1165
Volume 17, Issue 4
Displaying 1-4 of 4 articles from this issue
  • M. Abe
    1939 Volume 17 Issue 4 Pages 109-118
    Published: April 05, 1939
    Released on J-STAGE: February 05, 2009
    I have often written about the cloud “Turusi” and tried to solve its formation but I have not reached a satisfactory result. This time, I made an experiment in a wind channel by using heavy smoke to make a plane of discontinuity. The result was satisfactory and I came to a conclusion that the cloud “Turusi” will be formed, at the leeward side of the mountain, by the mutual collision of heavy lower atmosphere coming over the summit and both sides of the mountain.
    The wing like shape which is made experimentally by the smoke, explains not only the cloud formation of Turusi but the movement of its cloud particles.
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  • M. Hirayama
    1939 Volume 17 Issue 4 Pages 118-140
    Published: April 05, 1939
    Released on J-STAGE: February 05, 2009
    In the first paper, it was showed that the conductivity in the ionosphere is an asymmetric tensor, and the magnetic field produced by the atmospheric oscillations was calculated, ignoring the accumulation of charge on account of no disapperance of the divergence of the current. The idea that this accumulation must be canceled by the generation of the statical field as the atmospheric electricity teaches us, brings us to the very interesting result that the electric and magnetic fields are dependent of the conductivity, instead of .
    We calculated the magnetic field produced by the atmospheric oscillations strictly, starting from the fundamental equations and knew that when the oscillations is similar to that observed on the earth surface and the number of ions and electrons not different exceedingly, the current in the layer, 50km in thickness, and 120km in height, gives the observed amplitudes fairly, though phase difference as of old, and in the layer having large conductivity, the component with the same period as that of the oscillation, approaches to some constant, while the others, to the negligible small in spite of the variation of the conductivity with many periods, which shows the oscillation in such height very small.
    Considering the eddy viscosity which is too large in the air, especially in lower atmosphere, to disregard compared with, was investigated the oscillation due to the temperature changes consisting of the two parts… the one is that limited in the lower troposphere (within about 1km) in which the eddy thermal conduction prevails, and the other that slowly diminishing with height comparatively.
    The result gives a good explanation to the pressure variation in the upper free air calculated by prof. Fujiwhara and Mr. Takeda using the temperature variation over Lindenberg, and shows the oscillation in the stratosphere will be about 2/1π earlier in phase than that on the ground if the coefficient of eddy viscosity is 105-107 which seems to be reliable from the theory of the land and see breeze.
    Besides in the ionosphere, the presence of the temperature variation will be considered by absorption of the solar radiation even if it is not so large as some investigato_??_s believe.
    In any case, the diurnal variation of the earth magnetic field will be thoroughly explained, both in amplitude and in phase, by the atmospheric oscillation forced either by the one or two of the temperature changes in the lower atmosphere and in the stratosphere which must be expected to the further observations in future. Details will be published in The Geophysical Magazine in near future.
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  • M. Nakano
    1939 Volume 17 Issue 4 Pages 140-154
    Published: April 05, 1939
    Released on J-STAGE: February 05, 2009
    On the occasion of the cyclonic storm which swept along our Pacific coast from 1st to 5:h of April, 1936, conspicuous secondary undulations appeared on the mareograms of tidal stations in various parts of this country. In the present paper, is reported the result of investigation of periods, amplitudes as well as the time of occurrence of these conspicuous undulations, and some discussions are made on their relations with meteorological conditions. The results obtained are summarized in the following.
    (1) For stations situated along the Pacific coast of Honsyu, Sikoku and Kyusyu, conspicuous undulations of longer periods (proper oscillations of bays) began 6-12 hours before the time of nearest approach of the cyclonic centre to respective stations, and conspicuous undulations of shorter periods (swells or waves of 1-3 minutes periods) generally began somewhat later.
    (2) The conspicuous undulations of longer periods peculiar to the stations began about the time of arrival of 755mm isobar to respective station.
    (3) The conspicuous secondary undulations under question seem to have no close relation with the velocity of wind, gradient as well as the rate of variation of atmospheric pressure in the vicinity of the tidal station.
    (4) It seems that the present conspicuous undulations were not produced by the passage of lines of discontinuity and cold fronts as well as local showe_??_s. Besides, it seéms difficult to consider that the microbarographic oscillations in the vicinity of the tidal stations became the prime cause of the undulations.
    (5) The secondary undulations in question seen to have some apparent relation with the time variation of the atmospheric pressure gradient-the amplitude of the undulations is large when the rate of change of the pressure gradient is large.
    (6) It seems likely that the present conspicuous undulations were not produced directly by the meteorological changes in the immediate vicinity of the tidal stations, but chiefly by the waves which were produced once in some region near the centre of the cyclone, perhaps by some microbarographic change, and propagated toward the tidal stations.
    (7) As is naturally expected, the amplitude of the present secondary undulations has a close relation with the distance of the cyclonic centre from the tidal station. This relation is c_??_oser in the case of the undulations of shorter periods than those of longer periods.
    (8) There is a tendency such that the secondary undulation is large when the depression of the cyclonic centre is low.
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  • T. Kita
    1939 Volume 17 Issue 4 Pages 155-161
    Published: April 05, 1939
    Released on J-STAGE: February 05, 2009
    This short note gives the results of investigation of miniature climate of the city of Tokyo using the data of meteorological observation made at the Central Meteorological Observatory, the Sinagawa Storm Signal Station of the C. M. O. and the Takinokawa Meteorological Station during the year 1937.
    The results of investigation is that the town climate of Tokyo is not so remarkable as that of cities of European countries, but in winter night air temperature and humidity in and out of the town show great difference. This phenomena is rearkable since 1928.
    The city influence upon the distribution of wind is very small, as that upon the distribution of air pressure. So the study of this problem must use precise instrument for wind measurement. But the present writer used the data measured by ordinary instrument as the first step of investigation, and the position of observation were central Tokyo, Sinagawa, Takinokawa and kotobasi.
    The wind veiocity reduced at the layer of ten meters above the ground is greatest at Sinagawa and decreases in the order of Kotobasi, central Tokyo, and Takinokawa as the distance from the sea shore increases.
    When southerly wind blows the velocity at Kotobasi is strongest, this is due to not only topography or no high buildings near the station but effect of the Bay of Tokyo.
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