and K. Fujita, and published, though in mimeographed copies. By these 

 studies the following facts were revealed : (1) in the tropical latitudes 

 the streams of air flowing out from the anticyclones in temperate 

 latitudes form a kind of converging line with a band of cumulonimbus 

 along it, and (2) a weak high develops over the Equator which has great 

 influence upon the weather in the equatorial region. On the other hand, 

 K. Uwai studied the formation of typhoons on the equatorial front, and 

 T. Otani investigated in 1946 the mechanism and origin of rainy season 

 in the tropics. 



Concerning fog, an investigation on a large scale was made in 194:4: 

 at Hokkaido, by Y. Yoshida, K. Fukutomi, and Y. Miyake, under the 

 leadership of U. Nakaya, of the Hokkaido University. By this, precise 

 measurement of meteorological elements were made ascending to the 

 height of 1,200 m. above the ground by means of a big captive balloon. 

 The state of temperature inversion, diameter, and number of fog particles 

 with their absorbing power for the solar radiation, &c., were investigated 

 and many important results were obtained. This investigation had for 

 its object the artificial dissipation of fog. Also in the same year observa- 

 tions of radiation fog were made by S. Sakuraba, Y. Matsudaira, and Y. 

 Shibata, and a part of results thereby obtained were reported by Sakuraba. 



In relation to the explanation of visibility, aeroplane icing, and 

 precipitation mechanism, investigations on the hydrometeors as rain, 

 snow, fog, and dust particles were made during the period from 1940 to 

 1943 by Y. Takahasi, K. Ito, I. Imai, and others. In theoretical aspects 

 G. Yamamoto studied evaporation adopting the theory of boundary 

 layer in 1941, and T. Hagiwara treated the evaporation from rain-drops 

 since 1946. 



In 1941 and 1942 U. Nakaya studied the " frost heaving " of the 

 ground, while in 1941 experimental studies of artificial avalanches were 

 made near the Shimizu Pass in the Mikuni Mountain Range by the 

 Ministry of Transportation. In addition to this, R. Saito investigated 

 various properties of snow on the ground. The studies on these subjects 

 were mainly published in the journal Seppyo (The Ice and Snow). 



In 1939 and 1940 Y. Kato and T. Sato, of the Tohoku University, 

 made an absolute measurement of insolation intensity. In 1940 and 

 1941 Y. Daigo, M. Nakahara, and E. Fukui studied the correlation 

 between crops and weather, animal phenology, and the climate of Asia 

 respectively. At the agricultural experimental stations of the Ministry 

 of Agriculture and Forestry microclimatological studies since 1943 and 

 studies on the noxious insects of rice were performed from the meteoro- 

 logical point of view. H. Hatakeyama, S. Suzuki, A. Kimpara, and 

 T. Asada made a long study on the relation between fires and weather 

 conditions. Owing to the results obtained by this study, fire warning 

 based upon the weather conditions was put into practice all over the 

 country since autumn of 1947. Also the study of K. Wadati on the air 

 current accompanying cyclones and that of S. Syono on isallobaric 

 winds are to be mentioned here. Moreover, there are many investigations 

 on climatology and meteorology, of which " the World Meteorological 

 Data," " the Meteorological Data of Eastern Asia," and " the Aero- 

 nautical Weather Charts," published by the Central Meteorological 

 Observatory in 1942, 1943, and 1944, are regarded as representative. 



The following is the list of publications which appeared in this period, 

 most of which are in Japanese. In this list, among those publications 

 treating the same subject, only the latest one is mentioned. 



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