The Indian Ocean also responds to dynamical forcing
from the MJO, although the details of the response
are less clear here than they are for the Pacific. For
example, during MJO phase 3 there are westerly surface
wind anomalies over the central equatorial Indian
Ocean (Fig. 4c). These lead to a deepening of the equatorial
thermocline (positive D20 anomalies in Fig. 10a),
a raising of the surface (positive surface dynamic height
anomalies in Fig. 12c) and associated eastward surface
geostrophic current anomalies (Fig. 13c). These
anomalies are consistent with an equatorial Kelvin wave
packet in the central Indian Ocean. Simultaneously, the
raised thermocline in the eastern Indian Ocean (negative
D20 anomalies at phase 3 in Fig. 10a) is consistent
with a dynamic response to the easterly surface
wind anomalies there in the previous two MJO phases
(Fig. 4a,b). By phase 6, the positive equatorial D20
anomalies have moved eastward from the central to
the eastern Indian Ocean (Fig. 10a), but continuous
eastward propagation is not apparent. In phase 8, the
easterly wind anomalies over the central Indian Ocean
(Fig. 4h) give rise to dynamic anomalies of the opposite
sign, with a raised thermocline (Fig. 10a), and negative
surface dynamic height (Fig. 12h) and zonal geostrophic
current (Fig. 13h) anomalies.