temperature (SST) anomalies during December 2009 continued to increase across
much of the central and eastern equatorial Pacific Ocean (Fig. T18). Consequently,
all of the monthly Niņo-region
SST indices were above +1.4°C, except for the Niņo1+2 index (Table
T2, Fig. T5). The oceanic
thermocline, measured by the depth of the 20°C isotherm,
remained deeper than average across the equatorial Pacific (Figs. T15,
T16), with sub-surface temperatures in the
eastern Pacific reaching +2°C
to +5°C above average (Fig.
December 2009, convection was suppressed across Indonesia and enhanced over the
western and central equatorial Pacific (Figs.
and E3). Equatorial low-level
westerly and upper-level easterly wind anomalies (Figs.
T20 and T21)
were also consistent with El Niņo. Overall,
the oceanic and atmospheric anomalies reflected
a strong El Niņo.
the latest status of the ENSO cycle see the ENSO Diagnostic Discussion at: