The zonal geostrophic current velocities calculated
from the dynamic height are shown in Fig. 13. Eastward
(westward) geostrophic currents are clearly colocated
with positive (negative) equatorial dynamic height anomalies.
These dynamic anomalies are consistent with oceanic
first internal mode, baroclinic equatorial Kelvin waves
forced by MJO surface wind stress anomalies, as previously
diagnosed from TAO buoy data (Johnson and
McPhaden 1993; Cravatte et al. 2003; Roundy and Kiladis
2006).