The temperature conditions for the growth of snow crystals which were observed at Mt. Teine were compared with those which were determined by Nakaya, Hallett and Mason, and Kobayashi. The agreement was much better than with the findings announced by Gold and Power, and Murai. This improvement is probably because of the fact that in the Mt. Teine observations air temperature was not supposed from the data obtained by means of radio sonde sounding, but measured just in the cloud layer in which the snow crystals grew. Thus it is proposed that snow crystals of needle, sheath and dendritic type are sufficiently useful as indicators of cloud temperature during snowfall. Snow crystals of spatial type and snow flakes composed from far different types were also discussed from the point of view of cloud physics.
Photographic observations from aircraft were carried out on the snow clouds in December 1960. The results of observations will be described separately under the following three headings : that is, layer clouds, shower clouds and snow trails. It was concluded from analysis of the photograph of the layer clouds (Photo. 1) that the distance between two precipitating cells was reasonable in comparison with the calculated value of the wave length of the internal waves, as described in section 3 a). The formation of the ragged cloudlets near the shower clouds (Photos. 6 and 7) can be explained as due to lifting of the air by the downdraf t spreading out of the shower clouds. The observed shapes of the snowtrails in Photo. 5 was in agreement with that estimated from the wind profile as seen in Fig. 8.
The baroclinic and the vorticity-gradient effect upon the movement of the typhoon aretheoretically investigated by making use of the multi-parameter model. According to them, the baroclinic correction in evaluating the movement velocity seemsto be about 1/10 in the normal structure of the typhoon.
By using six-hourly upper air observations made at 97 stations in the northern hemisphere for ten-day period in September, 1958, the diurnal variations in height of isobaric surfaces, temperatures and winds in the troposphere except the boundary layer were investigated. The prominent features of the diurnal variation in height of isobaric surfaces are negative deviation from the daily mean at about 07 local time for each level, positive one at about 13LT, and the existence of two maxima and two minima at 850mb level. The average deviation of temperature for the air column, from 300mb to 850mb, is remarkably negative at about 07LT and positive in the afternoon.
The pressure waves produced by the nuclear explosion at Novaya Zemlya, the Arctic, on Oct. 30, 1961 were recorded in a number of microbarographs and barographs in Japan. Three kinds of pressure wave trains were detected, viz., the first train through the shortest distance, the second one through an antipodal course and the third one that is nothing but the return of the first train after a complete global passage. Energetically it will be the second largest explosion subsequent to the Krakatoa eruption in 1883, taking the records of pressure waves into consideration. The propagation velocities and the velocity-period relationship for the trains of the waves are examined, and the energy of the explosion is roughly estimated.
Correlation coefficients between the monthly mean temperature of Sapporo in July and 500mb heights in preceding months have been investigated. The 500mb heights used in this work are read off from the monthly mean charts of previous November, January, March and May for the period from 1946 to 1960 at 99 mesh points. As a result of screening calculation, high correlations to the temperature of Sapporo have been found on the 500mb chart for previous November in the vicinity of the Caspian Sea and for January in the south of the Lake Baikal with correlation coefficients of +0.74 and +0.72 respectively. While, in March and May, correlations are not so high as in November or January. A multiple correlation coefficient between the July temperature and the 500mb heights at the center of these high correlations in November and January is 0.87. This suggests that the temperature in July over North Japan is governed tatistically by the behaviour of the general circulation of previous November and January. Furthermore, the following two relations have also been discovered. One is that the 500mb height in November over the Caspian Sea is related to the formation of the Okhotsk Sea High in the following July. The other is that the 500mb height in January in the south of the Lake Baikal is related to the anticyclone of the middle latitude over the Northwest Pacific in July.