The surface dynamic height anomalies associated
with these thermocline displacements are shown in Fig. 12.
The negativeD20 anomaly (upward displacement of the
thermocline) in the equatorial western Pacific in phase 3
is mirrored by a negative surface dynamic height anomaly
(downward displacement of the surface) above (Fig. 12c).
This moves slowly eastward into the central Pacific as a
coherent, zonally elongated anomaly with a clear trough
(amplitude 0.35 m) along the equator by phase 5 (Fig. 12e).
By phase 7 (Fig. 12g), it has reached the eastern Pacific,
while a positive dynamic height anomaly has appeared
in the western Pacific. This then also propagates eastward
to the central Pacific by phase 1 (Fig. 12a).