East Asia and Western Pacific METEOROLOGY AND CLIMATE

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INTRODUCTION
In 1%6,
Bjerknes, using bathythermograph sounding data in the longitude
sector 140° —150° W (Sep., Oct., Dec. 1955 and Dec. 1957), studied the abundance
of warm water in the Central Pacific Ocean during the 1957/1958 El Nino event,
and suggested that the wanning could make the Hadley circulation run faster than
normal in the affected longitude sector and transport absolute angular momentum
to the subtropical jet stream at a faster rate than normal. The continued
poleward and downward flux of absolute angular momentum in the belt of the
surface westerlies could then be assumed to maintain stronger than normal in the
middle latitudes of the longitude sector. He also pointed out that the
subtropical High over the Eastern Pacific Ocean was farther south in the
1957/1958 winter than normal . Since that time, the correlation between
tropical ocean and global atmosphere has attracted more attention of
meteorologists and oceanographers. But those papers did not work out the
quantitative correlation by means of statistic theory and did not touch the
mechanism of the relations. The authors in the present article intend to discuss
the frequency responses among the indices of the subtropical High and El Nino,
and suggests an assumption for explaining the interannual variabilities of the
subtropical High over the NWPQ. The air-sea Interaction reasoning for the
Interannual variabilities of the subtropical High is based on evidences for
showing interannual variabilities of thermal structure and currents in the upper
WTPQ. It is assumed that the WTPO can affect the subtropical High over the IWO
more directly and essentially than the Eastern Tropical Pacific Ocean (ETPO) ,
and the correlation between the subtropical High over the N$PO and the ETPO Sea
Surface Temperature(SST) Is only appearance of the things*
LOW-FREQIBICY VARIABILITIES OF THE SUBTROPICAL HIGH OVER THE NWPO
In order tho describe the low-frequency variabilities of the subtropical High
over the N^PO, three indices, I.e. area, strength and westward extentlon of it,
are defined and the time series of the three indices are obtained (At a l month).
The area Index means the number of the grid points'(5°- lat.xiO 0 long.) enclosed
by the 588 isohypse on the 500 inb chart over the NWPO (110° E—180 0 . north of