ENSO & SST

ENSO and Sea Surface TEmperatures

Warm seas about and west of the dateline; warm ENSO event possible later this year

SST anomalies remain fairly weak across the Equatorial Pacific, with negative temperature anomalies east of about 150°W and positive anomalies about the dateline (around Kiribati). Sub surface sea temperature observations now show positive anomalies (exceeding +4°C at 150 m depth) in the central Pacific. In the Southwest Pacific, an area of much warmer than usual water at the surface (at least 1.5°C above average) has moved east since December, and now lies between New Caledonia, Fiji and Tonga. SST anomalies were at least 1.0°C above average off the Queensland coast, in the Coral Sea, and south of the Southern Cook Islands. The warmest surface waters (30-31°C) surround the Solomon Islands and an area further east around Tuvalu. Half of the global SST forecast models suggest the development of warm ENSO conditions in the months following the southern hemisphere wet season, although forecast confidence is lowest at this time of year. The January Southern Oscillation Index (SOI) rose to +0.3 with a 3-month mean of -0.1. The trade winds were slightly enhanced in the central Equatorial Pacific, with westerly anomalies in the west.

Sea surface temperature anomalies (°C) for January 2002

Mean sea surface temperatures (°C) for January 2002