ENSO & SST

ENSO and Sea Surface Temperatures

SOI strongly negative

Equatorial SST anomalies near zero

The equatorial Pacific remains in a neutral state. Equatorial SST anomalies are near zero, and have changed little from March. The monthly SOI was strongly negative, largely as a result of Madden-Julian Oscillation (MJO) activity in early April. The three month SOI (February-April) continues in the neutral range. For April and for February to April, the NINO3 SST anomaly was about +0.2°C, and NINO4 was about +0.4°C. Subsurface temperatures show negative anomalies near the surface in the eastern Equatorial Pacific, with positive anomalies in the farther west, both of which appear to be propagating east. Most of the global models indicate that neutral conditions are the most likely outcome for the rest of the year, though the chance of an El Niño developing is slightly higher than average.

Sea surface temperature anomalies (°C) for April 2004

Mean sea surface temperatures (°C) for April 2004