The monthly mean 500mb and 100mb charts were studied to investigate the relationship between the subtropical anticyclone in the troposphere over the Pacific and the anticyclone in the lower stratosphere over Southern Asia, which has recently come into notice. At 500mb, the western cell of subtropical anticyclone in the Pacific lies over the so-called Ogasawara anticyclone at the surface, and the center of the cell moves from south to north as the summer season progresses.
At 100mb, the anticyclonic area extending east from the anticyclone centered over Southern Asia in summer is laid over the Ogasawara anticyclone at the surface.
Further, the formation of closed high on the 100mb level occurs over the Western Pacific in spring, then the center moves toward west and reaches the Tibet Plateau in August.
It was found that, when the first formation of this closed high on the 100mb chart takes place over the oceanic area far south to Japan in April, the departure of isobaric height from the normal on the monthly mean 500mb chart in the Western Pacific in August of this year becomes positive, and when the stratospheric high forms first over the South China Sea, the departure becomes negative.
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