Journal of the Meteorological Society of Japan. Ser. II
Online ISSN : 2186-9057
Print ISSN : 0026-1165
ISSN-L : 0026-1165
Volume 14 , Issue 6
Showing 1-6 articles out of 6 articles from the selected issue
  • H. Arakawa
    1936 Volume 14 Issue 6 Pages 277-284
    Published: 1936
    Released: February 05, 2009
    This paper deals with a statistical study of the inversion and super-adiabatic lapse-rate observed in the free air at Kasumigaura, Japan proper.
    §1. The lower limit of the inversion is generally lower than 2.5KM in height. The inversion is about 4_??_6×102m of depth, and the temperature difference between the top and base of the inversion is within 4°C usually. The super-adiabatic lapse-rate is often observed in the free air. The. lower limit of the layer baving the super-adiabatic lapse-rate is generally lower than 2 KM in height. Such a layer is generally smaller than 5×102m in depth, and the heighest adiabatic lapse-rate 1.5°C/100m.
    §2. The relation of the air mass condition and inversion has been also investigated. The modified polar continental air in the colder half of the year is usually characterized by marked inversions due to subsidence of air. The polar maritime air is generally characterized by frontal inversions at the top, which occurred at a height lower than 2 KM. The tropical maritime air is often characterized by marked inversions so long as the southerly wind continues to blow strongly in the upper air and vanishes out if the wind becomes weak.
    §3. In the Far East, the precipitation occurs in advance of the cold front and clears up in rear of the cold front in the colder half of the year. The modified polar continental air mass is in front of the front and the fresh polar air mass in rear of the front. The modified air mass is characterized by the inversion which makes the subsidence dome. The dome at times practically intersects the ground surface along the periphery in rear of the modified polar air in mass, so that the fresh polar continental air mass flows in aloft above the dome first. So that strong convicetion and turbulence would result in front of the front. Thus there is strong lapse-rate to produce rain in front of the front. This model (Fig. 5) is quite contrary to the usual scheme proposed by J. Bjerknes.
    §4. The super-adiahatic lapse-rafe is often observed in the layer just below the base of the inversion, just above the top of the innersion or between two successive inversions.
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  • K. Itô
    1936 Volume 14 Issue 6 Pages 284-290
    Published: 1936
    Released: February 05, 2009
    (i) If we employ the smoked paper, to make a record of rain drops (experimentally: water or liquid drops), we will observe remarkable circular figures. (fig. 1, Pl. 3 fig. 1).
    (ii) S: soot,
    a: diameter,
    C: central spot (diameter: d), (Pl. 3 fig. 2),
    C': diameter of rain drops?
    v: volume,
    t: temperature,
    h: height of fall (experimentally). These values were measured. (fig. 2_??_fig. 7).
    (iii) Assuming the form of the drops is ellipsoid of revolution. (fig. 8).
    2/A was calculated. (fig. 9).
    (iv) A few of these figures leaves a tortoise-shell pattern on the smoked paper. (fig. 11, Pl. 3 fig. 3, 4, 5).
    (v) a, c[=1/2(b-a)] and n (nos. of radial lines) were measured. (fig. 12_??_14).
    (vi) This tortoise-shell pattern is formed as shown ihfig. 17. (?).
    (vii) The figures on the it clined smoked paper (inclination=α) were studied. (fig. 18_??_23, Pl. 3 fig. 6, 7).
    (viii) θ (fig. 18, Pl. 3 fig. 7) is formed with the splashed small water drops.
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  • S. Kuroda
    1936 Volume 14 Issue 6 Pages 290-299
    Published: 1936
    Released: February 05, 2009
    Hitberto it has been considered that in the design of the tower of electric transmission line the wind pressure must be taken as 15 times larger than that received by the loade _??_ area of one side of the tower. But this is by no means determined on the definite experimental as well as theoretical grounds. The present writer previously published a paper entitled as “About the wind pressure of tower” in the Journal of Aeronautical Research Institute, No.119. 1934, in which is discussed that such a value of wind pressure coefficient is too small and must be taken as 1.8_??_m;2.0. The present paper is written as the result of some experiments made for this purpose. Two rods, whose cross sections are such as circular, rectangular, etc. were placed in the wind channel and the wind pressure received by them and the manner of their vibrations were observed, changing their relative positions. And moveover, to make stream lines and the growth and decay of vortices occurred in these cases in the air current around these objects to be clearly visible the experiments were photographically made using the smoke in the current.
    The result of these experiments tells us that the falling down of tower sometimes experienced takes place on account of the strong wind pressure acted upon it and adding to it the resouance effect occurred in forced oseillations caused by the wind
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  • K. Uwai
    1936 Volume 14 Issue 6 Pages 300-307
    Published: 1936
    Released: February 05, 2009
    In the observations of shallow earthquakes made at stations near the epicente, we can find sometimes an azimuthal distribution of maximum vertical amplitude. Generally speaking, this distribution shows the maxima at places where the azimuthal angle ω=0 and π, and minima at ω=π/2 and 3/2π. This result of observation is in good agreement with that obtained theoretically considering Rayleigh waves generated by distorsional waves issued from an internal source of doublet in a semi-infinite elastic body. But when the axis of multiplet lies horizontally, the amplitude must become zero at ω=π/2 and 3/2π theoretically exceping the case of point source. Neverthless in actual observations, for example the Tenryûgawa earthquake occurred at Apr. 9th, 1935, the amplitudes at ω=0 and π did not show such a singularity. So that the author has examined whether these amplitude distribution.
    Can be explained or not by the Rayleigh wave cased by distorsional source of doublet, after Prof. K. Sezawa's method.
    Taking the free surface at, _??_=0 and the positive sense of the axis _??_ is di_??_ected downwards, the primary waves generated from the multiplet source (γ=0, z=§) may be expressed by in which and j2=ρσ2/μ, and θ1 is the inclination of axis of the multiplet, ωx' is the rotation about the axis perpendicular to the axis of the multiplet. ωy' is the rotation about the axis perpendicular to x-z plane. By the method of induction and proper transformation of axis, we can find the term which does not vanish at ω=π/ 2 and 3/2π, in the case of n=2, θ1=0, and takes the following form:
    By this term, we know that the Rayleigh wave can also be generated at ω=π/2 and 3/2π, and shows maximum amplitudes when the inclination of axis of multiplet θ1=0.
    This term is proportional to H1(2)(κγ)/γ, in which κ is the positive root of F (κ)=0. But the Rayleigh wave caused by the dilatational point source contains a term, proportional to H0(2)(κγ) etc. So that, if we know the stress distribution at origin, we shall determine whether the maximum amplitude actually observed in vertical component for shallow earthquakes is due to the former or latter mechanism of generation. But, in this paper, this problem is left till a future investigation.
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  • T. Nagata, K. Takahasi
    1936 Volume 14 Issue 6 Pages 307-313
    Published: 1936
    Released: February 05, 2009
    The pulsatory Oscillations abserved at Tokyo have been analysed with the method recently proposed by one of the authors and Mr. Husimi. The result of the analysis shows that the oscillation is due to the standing wave of the earth's block caused by some external forces. The Variation of the external force is calculated, and we find that is makes the type of quasi-periodic shock such as sea-tide at the coast.
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  • K. Fukuda
    1936 Volume 14 Issue 6 Pages 314-319
    Published: 1936
    Released: February 05, 2009
    With the mean values of meteorological elements only, it is not complete to express the climate at a place. But if the frequency of observed values for an element be possible to be calculated as a mathematical formula, e. g. where x is the observed value and β, h, x0, _??_, are constants. By two constants for one element the climate can be more completely expressed.
    The constants β, h, x0, _??_ take different values by following weather conditions, such as fine, rainy, etc. Accordingly, these quantities are used for the weather forecasting.
    As such elements: temperature difference between the summit and middle station of Mt. Tsukuba and vapour tension at 6 a. m. are used. These quantities have been considered as valuable elements for the weather forecasting, as Mr. Takayama, Dr. Fujiwara and the others already noticed A graph is made by the statistical investigation of temperature difference and vapour tension taking into account of the wind direction at that time. To obtain this graph is the main object of the pr_??_sent paper as the author believes that it must be useful to foresee the occurrence or unoccurrence of rain in the next day.
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