Journal of the Meteorological Society of Japan. Ser. II
Online ISSN : 2186-9057
Print ISSN : 0026-1165
ISSN-L : 0026-1165
Volume 19 , Issue 4
Showing 1-6 articles out of 6 articles from the selected issue
  • K. Takahasi
    1941 Volume 19 Issue 4 Pages 125-138
    Published: April 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    Winter weather in the Far Eastern Asia was studied from various stand point of view and the results are summarized as follows:-
    (1) The alternation of winter weather in the Far Eastern Asia is quite simple, and a typical distribution of pressure continues for several weeks together. This holds also for climate, and a similar climatic state continues for a long interval during a season.
    (2) The air temperature as well as weather in Japan are controled by the air temperature in Asiatic continent.
    (3) The wind velocity of the monsoon is a function of the pressure at the center of North Pasific Low, and the relation between them can be expressed by υ=υ0√770-P, where υ0 is a constant.
    (4) A typical pressure distribution of winter in the Far Eastern Asis is so called Seiko-Totei (high in the west and low in the east). This is produced by the temperature difference between continent and ocean, and the height of monsoon seems to below, say, a few kilometer. This pressure distribution can be considered as a result of an out flow of cold air from Siberia, and the amount of the out flow of air, calculated assuming that some amount of the energy of monsoon is disipated by the surface friction, agrees with actual observation.
    (5) The transfer of thermal energy due to the advection was calculated under very simple assumptions. It is found that the temperature of air mass can be considered to be conservative during a day, and the positive correlation of air temperature between the continent and Japan is found.
    (6) The temperature of air mass in winter is very low, and contains only a small amount of water vapour. Accordingly the precipitation depends greatly on the amount of vapour tension, and it was shown that the increase of vapour tension is important as a precursor of the rainy weather.
    (7) The amount of precipitation m depends on the pressure p as well as vapour tension and the relation between them is expressed in rough approximation by m=α(770-p) where α is a constant. This relation is proved theoretically by calculating vertical current due to frictional in-flow.
    (8) Depression is generated often near Taiwan in winter season and it is called as Taiwanbozu. This depression is a typical one in young stage and its structure is investigated, and a mode of the alternation of weather due to this depresson is described.
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  • K. Wadati, K. Matuo
    1941 Volume 19 Issue 4 Pages 138-141
    Published: April 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    In this paper is descrideed a new thermodynamic diagram, which is specially convenient for the routine work of weather forecasting. The abscissa is equivalent potential temperature, and the ordinate the barometric pressure. There are drawn such lines as temperature, maximum mixing ratio, dry-adiabatic and height. This diagram is more convenient compared with those hitherto used, as observed temperaiure ect. are represented by the curves standing almost vertically, and therefore the conditions of the upper atmosphere can be easily seen.
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  • M. Mukai
    1941 Volume 19 Issue 4 Pages 142-153
    Published: April 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    Von der Beobachtung ausgehend, dass die Durchsichtigkeitsgrenze der Seen nicht bestimms ist, suchte ich festzustellen, ob in den Mittel-und Bodenschichten die gleichen Erscheinungen auftreten. Der Verfasser nahm die dies bezüglichen Beobachtungen seit dem 9. VII. 1939 auf und hat sie bis heute fortgeführt.
    Der Kizaki-See hat eine Wasseroberfläche von 1.413km2. Seine Tiefe beträgt an der tiefsten Stelle 29.5m. Es handelt sich hierbei um einen natürlichen Stausee, der in nordsüdlicher Richtung verläuft. Die Beobachtung fand in der Art statt, dass der Verfasser Wasser aus dem See zwischen dem Mittelteil und dem Ausflussteil schöpfte und dieses auf seinen Lichtextinktionskoeffizienten untersuchte.
    Dabei haben sich folgende Beobachtungen machen lassen: Von Ende des Winters his Ende des Sommers, d. h. während der Stagnierungsperiode des Sees, weist der See in seiner Mittelschicht eine leichte Trübungsschicht auf. Darunteerstreckt sich wieder eine klare Wasserschicht Zu Beginn dieser Periode reicht diese klare Schicht bis auf den Grund des Sees, aber von der Mitte dieser Periode an trübt sich auch die Bodenschicht. Zwischen der getrübten Mittel-und Bodenschicht verbleibt eine klare Schicht. Das häng meiner Meinung n_??_ch mit der Seeströmung (bis zu einigen Metern unter der Oberfläche) zusammen, die den See vom Anfang bis zum Ende durchläuft. Das Auftreten der klaren Schicht, lässt sich wohl auf Quellen am Seeboden zurückführen. Als Grund für die Trübung der Bodenschicht lässt sich vielleicht die Kreisströmung des Sees aunehmen.
    Wenn dann im Herbst die Zirkulation der homothermen Schicht einsetzt, löst sich die bisherige Trübung auf, und der See weist von der Oberfläche bis zu einer ziemlichen Tiefe eine gleichmässige Trübung auf. Diese gleichmässige Trübung vertieft sich bei nahendem Winter immer mehr und reicht in der Mitte des Winters bis zum Seeboden. Dass die anfänglich gleichmässige Schicht verhältnismässig dick ist, ist wohl auf die Wasserträgheit zurückzuführen.
    Im allgemeinen wird der Grad der Trübung mit kommendem Winter immer grösser. Auch die Bodenschicht trübt sich auffällig. Ferner bilden sich zuweilen in der Nähe des Bodens kleine Trübungsschichten. Alle diese Erscheinungen sind wohl auf die Anhäufung des Windeinflusses zurückzuführen, der mit der Zeit immer stärker wird. Die Trübung der Bodenschicht und die kleinen Trübungsschichten verschwinden kurz vor der Vereisung.
    Dieser See gefriert in der Mitte des Winters. Die Verhältnisse unter der Eisdecke verbleiben die gleichen wie kurz vor dem Zufrieren. Es lässt sich nur eine geringe Aufklärung des Wassers feststellen, was wohl darauf zurückzuführen ist, dass der See im Winter keinerlei trübe Zuflüsse aufnimmt und die Windbeeinflussung durch die Eisdecke aufgehoben wird.
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  • R. Saitô
    1941 Volume 19 Issue 4 Pages 153-156
    Published: April 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    According to the author's observations, it is more plausible that downward movement of thaw water in snow is acsribed to connection of water films covering snow particles, rather than that it is caused by capillary attraction of water.
    The velocity of downward movement of thaw water does not depend on the specific gravity of snow. but on the size of snow grains. This is explained without difficulty by the water film theory, which is also powerful for explanation of “leader” (water stream) formation.
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  • T. Hoshi
    1941 Volume 19 Issue 4 Pages 156-160
    Published: April 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    It is occasionally experienced that the magnetic field and earth-current are disturbed by rain or snow storm. Drifting of electric charge on rain drop or snow flake by the strong wind is equivalent to an electric current, so that disturbances produced may be considered to do with the inhomogeneity of the density of the drift current which is probably due to random distribution of particle, rain or snow in the storm, and also to turbulent motion of surface wind.
    The present paper deals with the relation between the variation of vertical component of the magnetic field and component of the earthcurrent parallel to the drifting direction. According to the result, the ration of the amplitude of deflections, magnetic vertical force to earth-current, is given to be √σT (σ means earth's electric conductivity, and T the period of variation), and the phase of the vertical force retarded by 1/4π to that of earth-current. The practical magnitude of variation seems to be in a fairly good agreement with the above conclusion. Moreover, it offers another method of determining the electric charge on rain drop or snow flake in the excess of one sign, when the meteorology furnishes it with the knowledge of the boundary of drifting region and wind structure.
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  • K. Itõ
    1941 Volume 19 Issue 4 Pages 161-163
    Published: April 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    It is well known that the disc of the sun and moon near the horizon are deformed by the irregularities of stratification of the atmosphere. The author observed the figure of disc of the setting sun twenty-six times during the three years from 1933 to 1935. The disc was observed with a theodorite. Often it was photographed. Variations of the disc are classified into four types (Fig. 2) as follows.
    1. Ellipse and plate type.
    2. Separation type,
    3. Ellipse type,
    4. Ellipse and triangle type.
    But as in practice the variation of the disc is a complex phenomenon, that these 4 types represent only typical ones.
    The disc of a single discontinuous suoface was observed sixteen times in these figures and the one of double discontimuous surfaces was observed three times.
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