Vol. 1 (1950) No. 1 p. 1-5

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Vol. 1 (1950) No. 1 p. 9-18

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Vol. 1 (1950) No. 1 p. 23

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Vol. 1 (1950) No. 1 p. 62

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Vol. 1 (1950) No. 1 p. 67-76

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Vol. 1 (1950) No. 1 p. 81-132

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Vol. 1 (1950) No. 1 p. 133-146

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Vol. 1 (1950) No. 2-4 p. 206-210

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Vol. 1 (1950) No. 2-4 p. 226

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Vol. 1 (1950) No. 2-4 p. 229-298

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Vol. 2 (1951) No. 1 p. 6-29

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Vol. 2 (1951) No. 1 p. 30-32

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Vol. 2 (1951) No. 1 p. 52-56

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Vol. 2 (1951) No. 1 p. 60-63

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Vol. 2 (1951) No. 1 p. 69-72

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Vol. 2 (1951) No. 1 p. 106

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Vol. 2 (1951) No. 2 p. 135-149

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Vol. 2 (1951) No. 2 p. 157

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Vol. 2 (1951) No. 2 p. 158-166

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Vol. 2 (1951) No. 2 p. 168-177

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Vol. 2 (1951) No. 2 p. 180-187

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In this paper, equations of motion of a vortex in a non-uniform pressure field are obtained. Integrating the equations of motion over the domain of a vortex and separating the motion into that of a vortex as a whole and that within the vortex, equations of motion of a vortex are obtained. Among other things, important results obtained are as follows: (1) By the effect of the Rossby's force and the Coriolis force, the vortex moves on a cycloidal path, a cyclonic vortex eastward and an anticyclonic vortex westward. (2) The motion of a vortex in a uniform pressure gradient field is composed of four types of motion. (3) The well-known fact that cyclones tend to isallobaric lows is explained.

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Various writers have investigated the diurnal variation of wind at great heights by the analysis of pilot balloon ascents, and also studied the diurnal variation of pressure. at high altitude by the analysis of mean hourly pressures observed at mountains. Here the present author intends to show the relation of the diurnal variation of wind velocity and the diurnal variation of pressure using the data observed at the Mt. Fuji Weather Station.
A standard Japanese weather station was inaugurated on the summit of Mt Fuji (sometimes spelt as Mt. Huzi,3772m above M. S. L.,35° 21' N,138° 44' E) on July 1, 1932 and, since then, regular observations are undertaken by. well-trained observers, without interruption, even during the Great War II. Mt. Fuji Weather Station is, to my knowledge, the highest meteorological observatory in the world among the weather stations which take the hourly observations throughout the year. Quite recently, meteorological data for a 10-year period (Jan.1,1933-Dec.31,1942)has been published under the following title:
Central Meteorological Observatory, Tokyo,1949: FUJI-SAN NO KISHO (Weather at the Summit of Mt. FUJI), No. I, (in Japanese).
The hourly mean pressures and the hourly mean wind speeds observed at the Mt. Fuji Weather Station is given in Table 1.

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In discussing the structure of typhoon before, the author pointed out the existence of a maximum of wind velocity, that is, a sort of jet stream, just at the outer side of the tropopause funnel which forms the eye of typhoon.. The jet stream associated with the general circulation of the atmosphere seems essentially to be the same as that with the typhoon. Therefore the author tried to explain the phenomenon, adopting the following four assumptions: (A) stationary, (B) uniform in one direction, (C) frictionless, (D) autobarotropic, and deriving integrals from the initial equations of motion including inertia terms, in the same way as in the previous paper. The integrals represent respectively the law of conservation of (angular) momentum, vorticity and energy.
From the law of co n servation of energy can be derived an equation which determines the form of the surface of discontinuity. The surface inclines the steeper, the smaller the temperature difference and the larger the wind velocity difference between the both sides of the surface. In the neighbourhood of the surface, however, develops a mixing layer at the same time owing to the discontinuity of wind velocity. The thickness of the layer becomes the larger, the smaller the temperature difference and the larger the wind velocity defference, that is, the steeper the surface inclines, the larger the mixing, l ayer becom es in thickness.
From the law of conservation of vorticity it results that there must exist convective motions in the meridional sect ion of the atmosphere. Now, air particles displacing northward get extremely stronger in west wind velocity as they, approach the axis of the earth, as momentum is conserved along a streamline in an air mass. The strong wind thus developed draws down the surface of discontinuity lying above it a nd draws up that lying beneath. It follows thus that air particles can not proceed on their way over some extent northward, owing to the barrier which they form themselves. In, this way, th e meridional circulation of the troposphere presents necessarily a cellular strU. cture, and the air in lower latitudes can not arrive directly at the pole. Oil the other hand, the effect of fri ction is the most intense and, the, mixing layer becomes the largest at the northern end of the cell thus formed. The exchange of a ir between lower and higher latitudes is carried out only through friction. Thus the jet stream is developed the northern part of each cell, that is, at the northern end of the southern side of the mixing layer.
The structure of the jet stream thus derived is, shown in the figures. These figures, which are derived theoretically, coincide very well with those analysed hitherto by many investigators.

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The mass distribution of at mospheric ozone on the earth was calculated assuming that distributions of ozone on the northern and southern hemispheres are approximately the same only with a half year difference of phase. Results showed that the total mass of ozone is always constant. On the other hand, calculated amount of ozone by our previous theory decreases rapidly with increasing sec Z. Therefore, meridional distribution of photochemically formed ozone and that observed are quite different, but the total mass is equal to the latter and it becomes also constant on the whole earth. We considered that initial distributions are decided photochemically and act ual distributions are formed secondly by pole-ward transports of ozone in the stratosphere. The speed and direction of the transport and their seasonal variations were estimated by which the annual and meridional variation of ozone could be explained reasonably.

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Regarding the calculation of the secondary scattering of the solar radiation from the clear sky, a modification of the theoretical formula of A. Hamm. ad and S. Chapman (Phil.. Mag.1939)was done considering the effect of polarization cansed by primary scattering. A quantitative treatment became possible by the new formula in the vicinity of the zenith, that is, in the range from 0° to 45° of the zenith angle.

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The author and his collaboiators measured the bending directions of top-twigs of persimmon trees at about 230 points in the region of Akaho Fan, Nagano Prefecture, Japan, which covers an area of about 25 square kilometers.
They found that the bending of tree - tops was a very good indicator of the local prevaiding wind. The direction which they bend shows, with the inteival of confidence of about ± 15, ° the direction of the wind that prevails during the growing season of persimmon trees which is roughly from April to June.
Using the observed results, the author investigated the effects of the local topographical features and surface covers upon the prevailing wind of the locality.
Moreover, we made several a ctual and simultaneous wind observations at various places for some days when the southerly wind prevails at the surface of the fan. The precise local characteristics of the wind obtained till ough these observations agree surprisingly well with those estimated from the bending of the tree-tops.

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The author made a local obser vation of humidity distribution at Uchihara, Ibaragi Prefecture. There is a flat diluvial plateau surface dotted with paddy fields, cultivated fields and coppices. He studied on effects by such surface covers on humidity d stributions in daytime of summer. Differences between them reached 5-10%. And he discussed the magnitude of errors which are unavoidable in a mobile observation. They are caused by microfluctuations of atmospheric conditions and time change during the observation period. In order to lessen the second effect, he attempted a new method of repeated observations at the same piace at different times.

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There are many devices of telemetering rainfall-amount in the existing weather instruments. The authors explain on their remote rain gauge having a float as its sensitive element. This float has a function of making one contact every 0.1 mm of rainfall.
An impulsive signal is transmitted at each contact to the recorder at the base station.
This rain. gauge has. been tested successfully at Odaigahara-San, where rainfalls of about 1,000 mm a day are experienced several times a year.

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Equipments of a towing water tank for the hydrodynamical test of meteorological instruments and the method of experiment are described.
The basic tests of the convergent and divergent channels are conducted as fundamentals for ventilator tubes. The investigation on the im proved CMOS-48 radiosonde concerning the duct velocity distribution, the period of the cyclic flow pattern and the effect of the end plate and the deflector ale given. The connection of the tank test with wind tunnel experiment is also found.

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A rawin of double lobe system has been designed so as to improve the observational accuracy. The minimum elevation angle is about 18 degrees, which may be lowered by acertain value, preventing the incidence of the reflected wave witha metal net. The accuracy above this limit is about 0.4 degree.

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