Journal of the Meteorological Society of Japan. Ser. II
Online ISSN : 2186-9057
Print ISSN : 0026-1165
ISSN-L : 0026-1165
Volume 3, Issue 10
Displaying 1-3 of 3 articles from this issue
  • Takami ISIKAWA
    1925 Volume 3 Issue 10 Pages 255-266
    Published: November 14, 1925
    Released on J-STAGE: February 05, 2009
    It is generally accepted that one of the secondary causes of earthquakes and volcanic eruption is the variation of atmospheric pressure. The author of the present paper thought that a certain tectonic line or volcano has a special mode of dislocation or eruption, and consequently it is necessary to take a special condition of atmospheric pressure gradient proper to them when a fault or an eruption occurs there. In this paper this working hypothesis is accertained using seismometrical and volcanic data of semidestructive earthquakes and strong eruptions observed at our meteorological stations. The following conclusions are drawn:-
    (1) Dislocation may occur when the direction of atmospheric pressure gradient becomes perpendicular to the existing fault line and the amount of pressure gradient changes spontaneously from lowest or highest value. Moreover, when a pressure tends to increase in this case there occurs a destructive one, and when it is decreasing, a moderate shock may occur. Following few examples may support this theory;
    (2) When an extraordinary intense anticyclone covers the region surrounding a certain volcano even a slight variation of pressure may cause in many instances volcanic earthquakes and eruption. The examples of this case are found in the eruptions of Mt. Asama, Mt. Sakurazima, Mt, Bandai and others. All of these eruptions occurred, without exception, in the day of anticyclonic weather.
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  • Kinziro MATSUYAMA
    1925 Volume 3 Issue 10 Pages 266-271
    Published: November 14, 1925
    Released on J-STAGE: February 05, 2009
    The author puts his finger on the point that there are more than 30 species of cicada in Japan so that the Phenological reports in cicada must be prepared for each of the species. The mean dates of the first chirping of cicadas observed at Kagosima Meteorological Observatory are as follows
    Species Average date
    Terpnosia pryeri, Distant Last ten days of March
    Leptopsaltria japonica, How. July
    (Cryptotympana pustulata, Fab.?) First ten days of July
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  • Tokutaro UTUMI
    1925 Volume 3 Issue 10 Pages 271-275
    Published: November 14, 1925
    Released on J-STAGE: February 05, 2009
    The velocity of motion of the center of each cyclone is measured in a unit of 2° Latitudes or Longitudes of displacement per 6 hours. Following results show mean velocities of cyclones in various situation of cyclones and anticyclones, which appeared in the weather charts for seven years 1919-1925 issued from the Central Meteorological Observatory, Tokyo.
    From the above statistics we can draw conclusion that Okada's law is true so far as For Eastern cyclones are concerned.
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