Highlights – March 2012
La Niña continued to weaken during March 2012.
This evolution is reflected by the development of positive sea surface
temperature (SST) anomalies in the eastern equatorial Pacific and by a decreased magnitude of the negative SST
anomalies in the central equatorial Pacific (Fig.
T18, Table T2). The latest monthly Niño indices were -0.6°C for
the Niño 3.4 region and +0.3°C for the Niño 1+2 region (Table
T2, Fig. T5). Consistent with these conditions, the
oceanic thermocline (measured by the depth of the 20°C
isotherm) remained only slightly shallower than average in the east-central
equatorial Pacific (Figs. T15, T16), with corresponding sub-surface temperatures
were only 0-1°C below average (Fig. T17).
March, the equatorial low-level easterly trade winds were stronger than average
over the central and west-central equatorial Pacific (Table T1, Fig. T20). Convection remained suppressed in the western
and central equatorial Pacific and enhanced across Indonesia and the Philippines
(Figs. T25, E3). Collectively, these oceanic and
atmospheric anomalies reflect a weakening of La Niña conditions.
latest status of the ENSO cycle see the ENSO Diagnostic Discussion at: