The electrical resistance of soil changes abruptly upon freezing. (This journal, second series, 15, (1937), 321). The phenomenon can be applied to the estimation of the depth of frozen soil without turning up the ground. The writers attemptto make the estimation on a trip survey. Two fat iron rods are struck into frozen ground at the distance of 20cm and the electrical resistance between the rods are measured with an ohmmeter, commonly used for the construction and repair of radio-sets. When the point of the rod reaches the unfrozen part of the soil the electrical resistance changes rather abruptly and the depth of the freeze can be estimated on a curve of the resistance against the depth (see Fig. A No.1-C No.9 in the text). At the same time the ground is turned up to ascertain the result of the estimation. The abrupt change of the response of the rod to the hand, when the rod is struck into the ground with a heavy hammer, assists the estimation. The distribution of the depth of the freeze near Hunatu Observatory, at the northern foot of Mt. Huzi, is observed in this way.
In this paper the author presents a method of long range forecasting of the monthly mean air temperature T of August in Tohoku district. It is shown that this temperature T is derivable from the correlation (>0.85) between T and the difference of pressures at Husan and Zyosin of December of the former year. T has a period of about 30 years, and during the first 20 years T is comparatively low, and during the remaining 10 years is comparatively high.
An accelerometer for use on aeroplanes was designed and constructed at the Oosaka Branch of the Central Meteorological Observatory to investigate the turbulence or gustiness. 1. A direct reading accelerometer-is a simple instrument, having two pendulums each supported by a piano-wire. The instrument is put in a small box. This is used for a preliminary investigation of the period of vibration of aeroplanes caused by gusts. 2 An accelerometer with an air damper.-Tbe constants of this instrument are as follows: proper period T0=0.17sec, damping ratio υ=5.4, geometrical magnification V=3.41, statical deviation for the acceleration of 1g=26.7mm, coefficient of friction r=0.4mm_??_0.1mm. The record is obtained automatically with a smoked paper. A steel flat spring is used to give resistive force for an oscillating part having a mass of lead. The writing pen is made of a thin steel wire stuck on the end of the oscillating part, The air-damper consists of a piston with several small holes through which the air escapes.
The investigation of the persistence of weather using various kinds of meteorological elements was made by Prof. Fujiwhara and others. By the same method the author investigated the persistence of weather at Tyosi from 1926 to 1930, for the four seasons separately. It was assumed that the weather for both 30 minutes before and after the observed time is represented by that at the time. The following results were found, i) f1p and f2(1-p) increase with n. where p: the probability of one rainy hour. f1(f2): the coefficient to increase the probability of the occurrence of the second rainy (no rainy) hour. n: continued hours of _??_ weather ii) f1p is large in spring and winter, small in autumn and summer; f1p and f2(1-p) are large in summer and winter, small in spring and autumn; p and f2 are large in autumn and spring, small in winter and summer. p, f1, f2, f1p and f2(1-p) are respectively 0.130, 6.50, 1.12, 0.847 and 0.976, if they are calculated by the values of 1_??_24 rainy hours in year. iii) Mean continued hours of no rain are 26_??_37 hours, those of rain 4_??_5 hours. iv) Wn, t for no rain increase rapidly until n=ca. 25, then slowly, Those for rain have the maximum values at n=4_??_15. Where Wn, t: The probability of (t+0.5) rainy (or no rainy) hours after (n-0.5) rainy (or no rainy) hours. v) The distributions of continued hours of weather in year are shown by next formulas. FNn=500.0n-1.91……no rain FRn=257.0n-1.11……rain vi) The sum of frequencies in year if they are calculated per minute, are 1.5 times of the sum of the former. Maximum frequency for rain is observed at 30m, no rain at 10m. The sum of actual continued hours are the same to the former. vii) (a) fD2=f2 (b) fD1=f2 when rain is observed perio dically every day. (c) P=0.437 if it's calculated by the values of 1_??_300 no rainy hours in year, where, fD1(fD2): the coefficient to increase the probability of the occurrence of the second rainy (no rainy) day. P=the probability of one rainy day. vii) It seems that an intermittent rainfall must be considered as a continuous rainfall for the above calculation.
The present author made a theoretical consideration on the atmospheric tides, taking the vertical current into account. It must be noticed that the calculated amplitudes of the tidal oscillations are so small that they are compared with those of the temperature oscillations, -even M2 tides is 0·022mm in amplitude at the equator. Thus the observed semi-diurnal pressure change can not be explained as the tide, because not only the amplitude is very large but also the phase of the observed is advanced instead of retarded from the sun's culmination. (The author formally explained how it is caused by the diurnal temperature change.)
In the present paper, the author treated one case of oscillation of a water column: a vertical glass tube is immersed partially in water contained in a vessel, the lower end being very close to the bottom of the vessel, as shown in Fig. 1, and the water surface in the tube is initially raised or lowered and set in motion with initial velocity zero. If we assume the horizontal section of the tube to be very small as compared with that of the vessel, and horizontal velocity of the liquid to be negligible, the period of oscillation T is given by where H is the depth of the vessel, h the initial height of water level in the tube measured from the bottom of the vessel, g the acceleration due to gravity. This relation is shown graphically in Figs. 2 and 3. Fig. 3 includes also the experimental results, which agree almost prefectly with the theoretical ones. When the lower end of the tube is not very close to the bottom, the mouth correction of the tube can be found experimentally by obtaining the deviation of the observed periods from the ealculated by means of equation (9).
The energy of earthquakes may be considered as the change of the interior heat of the earth, though the exact mechanism is not yet known, and in a sense, it is mechanical action of the earth heat engine. The efficiency of such an engine was calculated, and is found that it is given by The numerical value of the efficiency is about 10-3, and hence it is seen that its efficiency is very low. On the other hand, the mean energy of earthquakes which occur in every year on the whole earth is about 102_??_ ergs and the energy loss due to the heat conduction in the earth's crust is about 2×1027 erg/year, hence the efficiency must be 1024/2×1027=0.5×10-3 which agree with the theoretical value at least in its magnitude. The discrepancy between them seems to be due to the assumption made in the calculation that the effect of friction may be neglected.
This short note is essentially a sequel to one which the author published recently in this journal(1). Annual values of mean daily maximum (or minimum) temperature at 20 stations are carefully calculated and analysed by means of the Method of Least Square. Assuming Θ=Θ0+b1t, or θ=θ0+b2t , where Θ or θ is the every year means of mean daily maximum or minimum temperature, t the time whose unit is one year. The four constants Θ0, θ0, b1 and b2 are determined by the well-known process. If b1 is positive, then the local mean daily maximum temperature is tending to increase year after year, and if b2 is negative, then the local maximum temperature is tending to decrease. The analysed results are shown in Table 1. In Table 1, we find that in large, developing cities such as Tokyo and Oosaka, the mean daily maximum temperature is almost invariable while the mean daily minimum temperature is tending to increase year after year with relatively large increasing rate. The increasing rate of mean daily minimum temperature is 2.6°C per one century at Oosaka and about 1.5°C per one century at Tokyo. The causes of these phenomena are probably due to both artificial generation of heat and atmospheric pollution.
H. Wexler recently discussed the formation of polar anticyclones and concluded that the isallobaric velocity component constitutes the primary important factor for the development of the anticyclone. In general the isallobaric component becomes smaller with the retardation of time rate of pressure fluctuation and the frictional inflow across the isobar becomes larger. In Wexler's paper the cooling of the atmosphere is of the order-1°C/day, therefore it is necessary to examine the air flow through bo_??_h agencies, isallobaric and frictional. It is found out here that in the polar continental air mass the frictional inflow surpasses the isallobaric flow. The main part of accumulation of air, however, comes from the superior atmosphere, therefore the present result has no essential contribution to Wexler's result. Next the dissipation of energy due to eddy friction has been considered. It is supposed that the dissipation becomes rapidly larger with increasing pressure gradient and becomes to prevent the development of anticyclonic energy.