Journal of the Meteorological Society of Japan. Ser. II
Online ISSN : 2186-9057
Print ISSN : 0026-1165
ISSN-L : 0026-1165
Volume 20, Issue 6
Displaying 1-5 of 5 articles from this issue
  • K. Takahasi
    1942 Volume 20 Issue 6 Pages 171-181
    Published: 1942
    Released on J-STAGE: February 05, 2009
    The weather in Japan has its own character for each season. For instance, the weather in summer and winter is stable while it is variable in spring and autumn. Ahalysing the daily minimum temperalure and synoptic charts, 10 seasons are shown. And the periodicity and durability of weather and the velocity of motion of cyclane, anticyclone, lines of discontinuity, region of rain and others are investigated.
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  • S. Sakuraba
    1942 Volume 20 Issue 6 Pages 182-186
    Published: 1942
    Released on J-STAGE: February 05, 2009
    The problein of geostrophic departure has recently been diseussed by various authors as R. C. Sutcliffe, F A. Berson, H. Philipps and others. In the present paper is investigated the geostrophic departure due to the field of barometric pressure, neglecting both the isallobaric component and the Sutcliffe's component (thermal wind effect termed by J. Küttner).
    The rectangular components of geostrophic departure are thus given by, discarding small quantities of small order, where ug and υg mean the components of geostrophic wind velocity.
    Now, as the distribution of pressure p, is adopted the from: Which is graphically shown in Fig. 1. Here P_??_=1000mb, A=B/D, B=10mb.
    The horizontal distribution of geostrophic departure corresponding to the above pressure distribution is also shown in Fig. 1 (arrows denote the direetion of departure).
    Further the horizontal divergence: is calculated and sbown in Fig. 2, in which _??_>0 means the divergence and _??_<0 the convergence.
    It is seen in Fig. 2 that in the east side of cyclone the convergence predominates and in the west side divergence predominates. This relation is reversed in case of anticyclone.
    The above relation well explains the asymmetrical structure and the eastward motion of cyclone in temperatnre latitudes.
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  • H. Arakawa, T. Hayasi
    1942 Volume 20 Issue 6 Pages 186-187
    Published: 1942
    Released on J-STAGE: February 05, 2009
    From the excellent Verbandelingen(1) of the Batavia Observatory we worked out for dry season (May-Oct) and rainy season (Nov.-April) separately, as seasonal variations may affect the values of characteristic properties of air masses to a considerable extent. In table 1 only readings taken during ascent at intervals of every 1km above M. S. L. have been included. We found that during the passage of the air from Batavia to Nanking(2), Hong Kong(3) or Manila(4), there are definite increases in temperature and humidity at all heights above the surface. These results indicate that while over China Sea or Sea to South of Japan the air is warmed at the surface, resulting in strong convection and thorough mixing.
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  • Y. Takahasi
    1942 Volume 20 Issue 6 Pages 188-206
    Published: 1942
    Released on J-STAGE: February 05, 2009
    Suppose that two solids of different matter extend to x<O and x>O, being in contact with each other at the plane x=0. If the temperature of these two solids at time t is given by u1 (x, t) and u2(x, t) respectively, the formula (5) or the simplifiedones (5I), (5II) give the temperature at the contact plane at the next time t+τ, which must satisfy the condition of the conservation of heat at that plane. And the temperature of the solids at t+τ, u1(x, t+τ) and u3(x, t+τ) can be calculated by the method for the ease, when the surface temperature of solid is given by a function of time. This method is not complete, and the error more or less occures in the neighbourhood of the contact pane, but the method is approval by the reason of the simplicity of calculation, if the variations of temperature are to be known only approximately. Refer also to my previous papers, printed in No.8, No.11, 1941, and No.1, 1942 of the same magazine.
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  • I. Osida
    1942 Volume 20 Issue 6 Pages 207-211
    Published: 1942
    Released on J-STAGE: February 05, 2009
    Recently Y. Takahasi has given a very convenient method solving graphically the problems of heat conduction. If u(x, t) is the temperature distribution at time t, then the temperature at t+τ is given by if we assume that τ is very small and neglect τ_??_. This can be easily verified by the aid of Taylor expansion and of the differential equation of heat conduction, i.e. Takabasi's method consists in evaluating the integral in (1) by the use of a planimeter. It is desirable, if possible, to replace the use of a planimeter by some simple constructions. It
    can be realized as shown in the following.
    We start, in place of (1), from which can be verified in similar way. Taking k=√6 and applying the Simpson's 1/3-rule, we have The operation on the right hand is easily parformable on the graph. Namely, the point of symmetry, of the point representing u(x, t) on the xu-plane, with respect to the middle point of u(x-b, t) and u(x+b, t) gives u(x, t+τ) (Fig. 1).
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