Journal of the Meteorological Society of Japan. Ser. II
Online ISSN : 2186-9057
Print ISSN : 0026-1165
ISSN-L : 0026-1165
Volume 19 , Issue 12
Showing 1-6 articles out of 6 articles from the selected issue
  • I. Imai
    1941 Volume 19 Issue 12 Pages 443-447
    Published: December 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    Ein durch die Wolke herabfallender Regentropfen fängt nicht alle Wolkenteilchen auf, die in seiner Fallbahn befindlich sind.
    (1) Das Zahlenverbältnis der aufgefangenen Teilchen zu den gesamten oder die “Ansammlungsfähigkeit” (α) der Kugel wind in gleicher Weise berechnet wie im Falle des zylindrischen Körpers.(1) Die Bewegungsgleichung eines Wolkenteilchens ist:
    worin bedeuten _??_ die Geschwindigkeit von Luft um die Kugel, _??_ die Geschwindigkeit des Teilchens, ρ die Zähigkeit der Luft, m und a die Masse und den Radius des Teilchens. Zerlegt man diese Bewegung in zwei Richtungen, d. h. in die Bewegungsrichtung des Teilchens und in die zu ihr senkrechte. so ergibt sich
    Hier ist 6πμa/m=K gesetzt. ds ist das Linienelement der Teilchenbahn, ρ ihren Krümmungsradius. φ und ψ bedeuten das Geschwindigkeitspotential und die Stromfunktion der Luft, und q=ds/dt=√_??_2+_??_2. Da ds/ρ=d tan-1y' ist, wird die zweite Gleichung von (2) folgendermassen umgeformt:
    Durch annähernde Integration unter Annahme von grossem V/KR erhält man für die Beziehung zwischen α und V/KR
    Das Resultat ist auch in Abb. 1 gezeichnet.
    (2) Die Fallgeschwindigkeit V eines Regentropfens mit dem Radius R ist unter Benutzung von Schmidtscher Formel berechenbar. Ferner ist der Wert K nur durch die Teilchengrösse a bestimmt. Daher wird für jeden gegebenen Wert von R and a ein bestimmter Wert von V/KR, deshalb auch von α berechnet (in %):
    Daraus kann man folgern, daß in gewöhnlichen Verhältnissen mindestens 80% Wolkenteilchen durch den fallenden Regentropfen aufgefangen werden.
    Download PDF (265K)
  • K. Takahasi
    1941 Volume 19 Issue 12 Pages 447-450
    Published: December 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    The pressure distribution on the earth surface is calculated, the atmospheric motion being assumed to be stationary and the air temperature to he only a funcfion of one horizontal direction. It is found that the pressure is compensated on the earth surface in the first approximation to any temperature distributions. As the consequence of above results, the upper wind is considered to be the thermal wind and it represents approximately the actual wind. When the upper layer is quite isothermal, high pressure is expected in cold region just as winter continental anticyclone. When the lower layer is isothermal, the effect is quite opposite. The pressure in the upper layer is also compensated in the first approximation so long as the temperatrure change is limited in the in lower layer.
    Download PDF (215K)
  • G. Yamamoto
    1941 Volume 19 Issue 12 Pages 450-454
    Published: December 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    It is generally believed by the studies of G. I. Taylor, D. Brunt and others that the transfer of heat by atmospheric turbulence makes the actual lapse rate to approach to the adiabatic one. In arriving at this conclusion they made an assumption that the atmospheric eddy comforms to the pressure of its surroundings utomatically in moving from one layer to another. This assumption is not true, in the actual atmosphere. Because if it were true, there should be no micro fluctuations of pressure in the atmosphere. But it is experimentally proved that in our atmosphere there also exist fluctuations of pressure as well as of temperature, density, wind velocity, etc.
    The present author has abandoned this assumption in considering the transfer of heat by turbulence, and has arrived at the conclusion that it is due to the action of atmospheric turbulence that one of the polytropic changes takes place in the actual atmosphere.
    Download PDF (349K)
  • H. Yagi
    1941 Volume 19 Issue 12 Pages 455-459
    Published: December 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    In the present paper is shown that the ageostrophic wind may be found approximately by the isogeostrophics, which are defined as the lines of equal geostrophic wind.
    §1. Ageostrophic wind
    The equa_??_ions of frictionless motion are (the notations are the same as those in Brunt's book)
    Neglecting the horizontal gradient of ρ and l, (1) is easily transformed as follows:-
    Now if the time variation of the velocity is small where ug, vg are the components of geostrophic wind velocity and _??_=∂p/∂t.
    Neglecting the products of small terms, u, v become, from (3)
    When the pressurè variations are neglected, where q is geostrophic wind velocity.
    Further, when the gradient of geostrophic wind velocity is small,
    From (6) it is seen that the direction of the ageostrophic wind is parallel to the isogeostrophies and keeps the large geostrophic wind to the righthandside in the northern hemisphere.
    (4), (5) and (6) give a good approximation to the true wind, but as it is troublesome to map out (4), (5) within few hours, it will be convenient to use the isogeostrophics with the isallobars, though (6) will fall below (4) more or less in accuracy.
    §2. Convergence.
    Integrating the equation of continuity from Z1, to Z2, and neglecting small terms, the following equation is easily obtained: where u', v' are ageostrophic wind velocity components, _??_ mean vertical velocity and divergence through the layer between the heíght Z1, and Z2.
    From (6) it is known that, at the region where there is divergence of the isogeostrophics, there is convergence of the horizontal flow. Therefore, from (2.1) _??_ may be evaluated, and then the precipitation will roughly calculated. The author used this method to the surface isobars and the estimated isobars at the height of 1km and 2km.
    The author applied the isogeostrophics to every day weather forecasting and found that the divergence (convergence) agrees with the rainy or cloudy region (the fairy), and the estimated precipitation, agrees with the actul one.
    Download PDF (278K)
  • N. Inoue
    1941 Volume 19 Issue 12 Pages 459-467
    Published: December 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    Calibration of hair hygrometers of polymeter type was made through a complete cycle of relative humidity changed from 100 per cent. to 5 per cent., at temperatures of 20°, 5°, -5° and -10°C. In the wide range of humidity such as from 30 to 100 per cent., these calibrations showed an evidence of remarkable hysteresis effect, in other word, greater indication for the same humidity in the case of increasing humidity than in that of decreasing. The maximum deviation of these indications was about 10 per cent, in relative humidity scale. The same hysteresis curve could be reproduced in every calibration of the same hair hygrometer and was not influenced by temperature. Other hair hygrometers, however, showed quite different forms of hysteresis curve. In the final stage of a cyclic process of calibration, that is, in the saturated atmosphere after the course of increasing humidity, the pointer of hygrometer indicated at first the scale over 100 per cent. and in the case of room temperature, it restored to 100 per cent in a few minutes. The time of its restoration was longer at lower temperature; for example, about 24 hours at -5°C. Such a hysteresis phenomena would prabably be due to the lag of formation of meniscus in the empty cells, in the course of capillary condensation of moisture in numerous cells contained in the hair. The time lag of indication, which means the lag of hair in getting to moisture equilibrium to the surrounding atmosphere after a rapid change of humidity, is greater at lower temperature. This lag, however, seems to have no relations to the above mentioned hysteresis phenomena.
    Download PDF (614K)
  • Y. Daigo
    1941 Volume 19 Issue 12 Pages 467-474
    Published: December 05, 1941
    Released: February 05, 2009
    JOURNALS FREE ACCESS
    In recent years much has been studied about the effects of various heteroauxin treatment on the germination of seeds, but the effects under various temperature are not studied so much.
    Therefore, the author studied the influence of the heteroauxin treatment on the germination of aquatic rice seeds of three varieties, Senichi, Sinriki and Rikuu No.132, at various condition of alternating temperature by the following method:-
    Aquatic rice seeds of the three varieties are soaked in 5×10-4%, 25×10-4%, 75×10-4%, 375×10-4%, 1875×10-4% heteroauxin solution, for each 2, 4, 6, 8, 10, 24, 48, 72 hours respectively, while as check lot they are soaked also in plain water. All of the lots is divided into two series. Namely, one of the series is set in room temperature (Fig. 1) and the other in a thermostat, in which the range of temperature is larger than that in room temperature, for above mentioned each treating hours. (Fig. 2.) In this way, we obtain 267 lots in all.
    After the fourth days from the beginning of the treatment, we count the number of germinated seeds and the percentage of germination for each lot, for each day, was computed as shown table 1.
    In the results of this experiment we see clearly that the heteroauxin treatment accelerates the germination energy, but no significant differences of the germination capacity by the heteroauxin treatments or those under the different temperatures were established in this germinationtests.
    Download PDF (675K)
feedback
Top