East Asia and Western Pacific METEOROLOGY AND CLIMATE

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expands, more and more interactions in the various components
of the earth system become important. There is a hierarchy of
time scales leading to a hierarchy of complexities. It is a
strong challenge for earth scientists to understand the
various complexities of major physical processes that
contribute to the climate changes in the proper corresponding
time scales. How can we build these processes in climate
models to predict future climate changes One key step is to
understand the air-sea interactive processes that determine
the flux fields on the time scales of interest.
II.
The Western Pacific Ocean
The Pacific Ocean is our largest ocean basin. Observational
data and modeling results point to the Pacific Ocean as the
dominant basin in terms of driving the high-frequency side of
climate changes, i.e., in the TOGA El Nino/Southern
Oscillation (ENSO) signal domain. In addition to the huge
area and strong boundary current, the Kuroshio, there are many
physical features in the Tropic Pacific, especially in the
Western Pacific that are extremely important to climate
changes. These features are:
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The huge warmest water pool in the world ocean;
The deepest thermoline in the tropical oceans;
A transient zone between the monsoon system and
the trade winds;
A region of strong atmospheric convections closely
correlated with a warm water pool;
A region of high variations of the Intertropic
Convergence Zone and the Southern Pacific Convergence
Zone;
The rendezvous area of the South Equatorial Current
and the North Equatorial Current and the Origin of the
North Equatorial Counter-Current, the South Equatorial
Counter-Current and Equatorial Under Current; and,
The source region of forcing, for equatorial large
scale waves, oceanic large scale, low frequency waves
along the equatorial wave guide.
III. The TOGA Program
The TOGA program is a major component of the
WCRP aimed