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Volume 15, Issue 12
Displaying 1-9 of 9 articles from this issue
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Y. Miyake1937 Volume 15 Issue 12 Pages 529-531
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSImpurites in the air of central Tokyo have been chemically estimated since March 1937. The results are as follows.
Ammoniak shows a remarkable seasonal variation from spring to summer, that is the gradual increase corresponding to its content in the soil.View full abstractDownload PDF (188K) -
H. Arakawa1937 Volume 15 Issue 12 Pages 532-534
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSIn his study on the effect of coasts on winds, the present author discussed two primary factors, i.e. surface friction and slope of the coastal region which was first introduced by Georgii. In order to discuss the effect of the surface friction, he considered coasts which were practically fat so that no effect due to dynamical ascent of wind up slopes need be considered. The mathematical treatment of air flow over coast3 is studied with simplified assumptions as to the conditions of flow together with the assumption of a periodic surface friction. A wind in the transition from sea to laud experiences a strong retardation or decrease in velocity on account of the increase of friction. The continuity of the air flow demands that at each place at which this decrease occurs there is a corresponding or compensating ascending flow.View full abstractDownload PDF (164K) -
Y. Yokouti1937 Volume 15 Issue 12 Pages 535-540
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSSpecific Resistance (reciprocal of specific conductivity) of rain was measured at Kakioka Magnetic Observatory. The direct current method was adopted and the applied voltage was about 110 volts. Its mean resistivity was 1.7×105 Ω√cm3 at 15°C, ranging from maximum value of 6.5×10_??_ Ω√cm3 to minimum value of 2.1×104 Ω√cm3. It was generally of small value at the beginning of rainfall and gradually increased as it continued. The resistibity of rain varies as the nature of rain; the highest value was observed at tyhoons and the smaller values at cyclones and discontinuous lines and the lowest value at thunderstorms. The maximum was observed in October and minimum in April.View full abstractDownload PDF (440K) -
S. Ikeda1937 Volume 15 Issue 12 Pages 541-547
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSIn my previous paper, I discussed the inertia effect of float of Dines' tube-anemometer. Here I have intended to discuss the effect of friction of pipe-walls on the air-currents.
I derive the method of calculation of time-lag and modification of record in the case of squall and lull.
The relation between velocities of air-current in the pressure and suction tubes w1, w_??_ and motion of float dx/dt is approximately given or
where α: uppermost radius of float.
R1, R2: radius of pressure and suction tubes respectively.
When the velocities of air-current in the tubes are laminar, we have
where μ: viscosity of air.
L1, L2: length of press. and Sue. tubes respectively.
p1, p2: air pressure at above and below the float.
pα, pβ: wind press. and suction press. at head portion of the anemometer.
(1) is written as
It is transformed as
since p1-p2=cm2X2, pα-pβ=cm2X'2
where X is the rise of float which is keeping with p1-p2, and X' is supposed position of float to keep with pα-pβ.
The solution of (3) when X'=coast and at t=0 X=X0 are
This formula is used for the motion of float when the wind varies discontinuously from X0 to X'. Adopting the numerical values for a, R, L, etc. we can estimate the time lag and mode of modification in special case above mentioned.
If the motions in the pipes are turbulent moi ons, we have.
D: experimental constant.
The relation between X' and X is
When X'=constant and at t=0, X=X0, we have
If the value of D is known we can calculate time lag T0 numerically. It is independent of wind difference X'-X, and differs from the case of laminar flow.
At all events, experiment of the anemometer at actual condition is necessary.
But only from rough estimation by the above formulae, it seems plausible, that the anemograph which in this country commonly used of pipes of 7.5-10.0 metre length and 1cm diameter cannot records successfully the wind varying more rapidly than 10sec. period.
In conclusion, I wish to express my sincere thanks to Dr T. Okada, Director of the Central Meteorological Observatory, for his valuable information on this subject.View full abstractDownload PDF (397K) -
K. Agematu1937 Volume 15 Issue 12 Pages 547-549
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSThe present author reports the observation of the growth of hoars made at the Meteorological Observatory at the top of Mt. Fuji.
At the top of Mt. Fuji, the conditions being better for the hoar-sublimations, the beautiful crystals can be observed in general.View full abstractDownload PDF (222K) -
S. Sakuraba1937 Volume 15 Issue 12 Pages 550-555
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSThe wave theory in cyclogenesis adopted in polar front theory is based on the theory of gravitational waves generated along a discontinuous surface separating two air masses of different constituent. The wave motion thus generated develops into the vortical motion and takes the nasent stage of a cyclone.
The vortical motion in such a scheme however means that of a horizoutal vortex, thus the transformation is necessary from a horizontal to a vertical vortex under some agency. The norwegian school ascribes it to coriolis' force and S. Fujiwhara to the kinematical characteristic of vortex itself.
The author replaced a horizontal vortex by a cellular vortex and mathematically proved such a transformation as supposed by the norwegian school.View full abstractDownload PDF (282K) -
H. Arakawa1937 Volume 15 Issue 12 Pages 555-558
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSRealizing the importance of a quantitative method for identifying air masses, Prof. C. G. ROSSBY presented the consistent definitions of the equivalent-potential temperature and equivalent temperature, and developed the diagram which bears him name(1). It should be mentioned here that the wet-bulb-potential temperature and wet-bulb temperature can equally be used for the purposes of identification(2). So far as I know there is no unified presentation of simple, analytic definitions of these temperatures at present, so that it might be pointed out that the task of writing such a treatise is no mean one.View full abstractDownload PDF (237K) -
H. Futi1937 Volume 15 Issue 12 Pages 558-572
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSSie Napier Shaw, in his “Manual of Meteorology (1927)”, has given a very interesting diagram showing the distribution of temperature up to 25 kilometers over the northern hemisphere for summer and winter with continuous lines. K. R. Ramanathan has published in “Nature (June 1, 1929)” a very interesting chart which modified by using all the data available at that time and L. T. Samuels has made a very interesting comparison of his (Ramanathan) chart with the results of some new aerological observations made in U.S.A. which were not included in the data comprising the chart.
Recently E. Palmén has shown in “Meteorologische Zeitschrift (1934)” a very excellent diagram by using Rolf's observational results at Abisko (68°N) and Weickmann's data observed by “Graf Zeppelin”
On the other hand V. Bjerknes, J. Bjerknes, H. Solberg and T. Bergeron have given in their “Physikalische Hydrodynamik” reasonable diagrams different from the other's by showing the distribution of temperature over the northern hemisphere and southern hemisphere (0°10°S) for summer and winter separately.
In this paper, therefore, the author showed diagrams over northern hemisphere and southern hemisphere (0°-30°S) for all months, and various diagrams showing annual ranges of temperature at all heights, annual changes of tropopause-heights in the meridional section and so on, by adding newest data from 1934 at the stations such as As (60°N), Agra (27°N), Poona (19°N), Madras (13°N), Ellendale (46°N), Omaha (41°N), Dallas (33°N), and Pretoria (26°S).
The principal features of the diagrams may be briefly summarized (1) The seasonal variations of temperature in the stratosphere over the earth are very great (see Fig. 6-Fig. 17 and Fig. 21), especially in the polar region. (The seasonal development of the tongue of warmer air from 45°N to north-pole is shown in the diagrams, in which the dotted lines are based on very few observations, or nothing and are therefore mainly conjectural.)
(2) The coldest air over the earth, of temperature about 185°A, lies at a height of some 17 dyn. km. over some equatorial region in the form of a flat ring surrounded by rings of warmer air and the center of the coldest region moves from about 4°N to 4°S. (see Fig. 19)
(3) The surfaces of tropopause are relatively flat between 23° and 0° for winter and between 32° and 0° for summer in the equatorial region, and between 55° and 90° for winter and between 60° and 90° for summer in the polar region. In winter there is a tendency for the height of tropopause to decrease from 25° to the equator and this tendency is explained by the effect of high pressure in the Asiatic continent. (see Fig. 18)
(4) The annual change of temperature is relatively small in the tropopause-surface (see Fig. 21).
(5) From about 45°N to the pole in the annual variation of temperature at all heights, the maximum rises in summer and the minimum in winter (As-type, see Fig. 23). From about 45° to the equator the same in troposphere, but on the contrary in the stratosphere the maximum in winter and the minimum in summer (Agra-type see Fig. 23 and Fig. 24).
(6) The annual variations of temperature in the stratosphere over the polar region may be explained by the annual variations of ozone and the height of tropopause in the meridional section also by means of the average height of ozone.View full abstractDownload PDF (1005K) -
[in Japanese]1937 Volume 15 Issue 12 Pages 573
Published: December 05, 1937
Released on J-STAGE: February 05, 2009
JOURNAL FREE ACCESSDownload PDF (102K)
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