Studies of Atmospheric Disturbance. Part. III

[摘要] Chapter 4. Discussion of barotopic and baroclinic terms. In the present chapter, we discussed the baroclinic and barotropic terms which play importantroles in our wave theory of vortices. When the troposphere is continuous medium, the baroclinic term is devided into three parts: Suffices 0 and H are used to denote quantities at the earth surface and tropopause. Using IpP and IpH and (21.9) in chapter 2, we can shaw that cyclones with large longitudinal temperature gradient develop or decay according as their eastside is warmer and colder than the westside, on the other hand, those with latitudinal temperature gradient do not change their intensity even though the gradient is large. This phenomenon predominates in middle latitude. It is recently remarked in our meteorological school. Next we derived the formula for the case where transitional layer of discontinuous surface exist in the troposphere. Using the following values: R=2.9×106C. G. S., g=980C. G. S., pM=200m. mHg, TM=220°, T=250°, H=106cm the ratios between IpP, IpH and ItT become as follows:The harotropic term is devided into seven parts:whereWe discussed the above terms briefly and compared with Diness statistics aboutupper atmosphere.Chapter 5, Anticyclone. Comparing with temperature distribution in the upper atmosphere with our results, we cansee that the high belt of middle latitude is caused by KTH and from which the former has close relation with the inclination of the tropopause. The large Siberian anticyclone is considered to be caused by KtT. From the above result we remarked tdat the travelling anticyclone which starts from the Siberian anticlone in winter is decayed by heating action by various causes and that is questionable that the low travelling anticyclone transforms into the high warm anticyclone.Chapter 6. A Type of Formation of Depression of Middle latitude. The depresion of middle latitude is considered to grow from the instability wave on the polar front by Norwegian meteorologists. In spite of success in verifying the existence of the instabilty waves by shearing instability at a surface of discontinuity, they can not analyze mathematically and physically the ewolution from vave to vortex Even though all cyclones of middle latitude do not birth on the polar front, it is recognized that many cyclones birth on the front or frontal zone. In the present chapter, we give the interpretation of the evolution from wave to vortex, but our theory is not confined to the case of wave. The pressure of the upper atmosphere decrease from equator to pole and in the middle latitude where gradient is very large, or IpP and IpH have large negative value and the longitudinal pressure gradient is very small. Now, if the boundary surface between two different air masses which lie side by side along the latitude is affected by any disturbance, e. g. an instabilty wave due to Godske and others, the longitudinal temperature gradient in the lower atmosphere increase. When the temperature gradient is from east to west, ∂T0/∂y is positive. The baroclinic terms increase in their absolute values and the signs are negative. Then the vorticity of vortical wave intensify in cyclone sence. by the result of chapter 2 (2.19). This is the evolution of cyclone from wave to vortex. Thus the instability wave is not a necessay condition for the formation of cyclone. Further a depression may be able to birth on the fornt or frontal zone when any disturbance comes in theupper atmosphere over there. The formation of family of depressions is easily understand from our stand point.

[学科分类] 大气科学