Journal of the Meteorological Society of Japan. Ser. II
Online ISSN : 2186-9057
Print ISSN : 0026-1165
ISSN-L : 0026-1165
Volume 41, Issue 2
Displaying 1-4 of 4 articles from this issue
  • Choji Magono, Tsutomu Takahashi
    1963 Volume 41 Issue 2 Pages 71-81
    Published: December 28, 1963
    Released on J-STAGE: October 19, 2007
    The electrical charge on an ice-coated probe during riming and glazing in natural cloud droplets was observed at the top of a mountain. The observations were carried out under a condition of sufficient shielding from the external field.
    The conclusions obtained were as follows :
    1. When micro snow particles were contained in air, the probe was generally charged positively, but when snow particles in the air were relatively large and round, the probe was electrified negatively.
    2. The necessary condition for the electrification of the probe was not the existence of cloud droplets in the air, but the collision of snow particles in the air with the probe.
    3. The difference between the temperatures on the surfaces of snow particles and on the surface of the probe had some effect on the electrification of the probe, but the sign of it was opposite to that found by Reynolds, Brook and Gourley.
    From the results, it is considered that micro mechanism of the collision of the snow particles with the probe is significant for the electrification of the probe, for examples, the tearing off of fine structure of the snow particles, and the existence of liquid film on the surface of the probe.
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  • M. Aihara
    1963 Volume 41 Issue 2 Pages 82-107
    Published: December 28, 1963
    Released on J-STAGE: October 19, 2007
    In order to know the energy cycle of the baroclinic disturbance in a zonal flow, the two-level geostrophic model with the adiabatic and hydrostatic assumptions was integrated for long time period. The 6 components of the trigonometric function were used to represent the broad-scale features of the motions in the model atmosphere. Time behaviours of the energy transformation functions, meridional transport of sensible heat and eddy zonal momentum associated with the development of the baroclinic wave are followed and analysed. The dependencies of energy cycle upon the scale of the disturbance and the zonal vertical shear are examined by changing the zonal wave number from 14 to 1. The period of the energy cycle which is mainly governed by the baroclinic process, is of the order of a week or ten days, however, the occurrence of the considerably long time period is possible, if the initial assignment of the vertical zonal shear is close to the critical value to create the baroclinic instability.
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  • K. Takeuchi, O. Yokoyama
    1963 Volume 41 Issue 2 Pages 108-117
    Published: December 28, 1963
    Released on J-STAGE: October 19, 2007
    The scale of turbulence in the surface boundary layer, l is investigated as a function of the thermal stability, ξ(ξ_z/L, L≡V*3/( kg/T0q/cpρ)). When the scale function, ψ is introduced as l(ξ)≡kzψ(ξ), the nondimensional wind shear, s(≡kz/V∂U/∂z) can be represented as follows: S4-γξS3-ψ-4=0 where γ' is constant. So-called Ellison-Yamamoto-Panofsky's equation is included as a special case (i.e., l=kz or ψ=1). And then the equation is solved exactly as a function of ξ and also ψ.
    Now, the data obtained during "Project Prairie Grass" and also taken by Gurvich show that ψ is quite varied with ξ. A t present, there seems to be no way to estimate the formula of ψ except making use of the few available observational data. From the data taken during "Project Prairie Grass ", ψ is evaluated assuming that the vertical scale as a function of ξ is similar to the horizontal : ψ(ξ)=σ{ξ-(2+σ-2)1/2} where σ is constant. And then the concrete formulae of S are obtained in the various thermal conditions.
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  • Kozo Kimura
    1963 Volume 41 Issue 2 Pages 118-134
    Published: December 28, 1963
    Released on J-STAGE: October 19, 2007
    The way in which weather elements such as temperature change with the seasonal march is not continuous as may be suggested from the change of sun's altitude but is discontinuous as shown in Fig. 1.
    The present study is made in an attempt to confirm this fact. From the features as shown in Fig. 4 and other evidences the following conclusions are reached
    1. Independent from topography, latitude and the climatic change, there exist definite temperature limits as given in Table 3. In each season, temperature change of any place is confined statistically within a range called a ″step″ which is defined by a pair of such temperature limits.
    2. The conventional season shall be divided into smaller parts, each of which may be called a ″sub-season ″. The sub-season is limited by one step or adjacent two steps. Then the construction of such sub-seasons and the mechanism of their succession are studied based on Fig. 7 and other evidences. However, it is found that they cannot be explained by the condition of pressure pattern and the air-mass theory. Furthermore, some questions arise on the air-mass theory itself.
    As is seen in Fig. 8, there exists a high correlation between the location of the stationary front in summer and the temperature limit. This suggests that the profile of zonal current is related closely to the sub-season. But this relation is not functional ; the change of subseason in a year takes place more frequently than that of zonal current. In view of the results of the present study, it is pointed out that the stepped character of seasonal change is not a phenomenon to be explained simply by the existing concepts but includes a number of problems that need further examination.
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