Dynamic Climatological Consideration on the Alternation of Spring Weather in the Far East Asia

Abstract

Characteristic natures of the alternation of spring weather in the Far East Asia were investigated and the results are summarized as follows.
1) Mean velocities of the motions of cyolone, anticyclone, rainy region, line of discontinuity and yellow sand are calculated and it is shown that the movement of lines of discontinuity and yellow sand are quite differnt from the others.
2) The velocity of cyclone is determined by up, er air current and nature of frontal zone between two air masses. When the effect of frontal zone is predominated, the cyclone is considered as to be the wavy motion of the frontal zone. This is treated mathematically under a simple assumption and travelling of cyclone towards east is proved.
3) The motions of discontinuity and yellow sand are determined by out flow of cold air from Asiatic continent and its motion is calculated.
4) Characteristic nature of the season is oscillative change of various meteorological elementswhich can be explained by the wavy movement of frontal zone between Ogasawara and Siberia air masses.
5) It is shown that there is a special weather which can be considered as a diffusing phenomena of Ogasawara air mass in horizontal direction and the amount of precipitation is calculated by solving the equation of diffusion and the results are satisfactory.
6) Statistics of characteristic weather for various air masses are made.
7) Structure of the typical cyclone of the season is investigated and it is founl tbat it resembles to the eyclone in Europe as a whole, but the direction of movement is different, hence the alternation of weather due to the passage of the cyclone is rather different from that in Europe.