ENSO & SST
ENSO and Sea Surface TEmperatures
Warmer than average seas around Nauru
SST anomalies have still shown little change since the middle of the year, with an area of warm 30°C surface waters and positive SST anomalies (at least 1.0°C above average) around Nauru, between the Solomon Islands and Western Kiribati. SST anomalies also continued above average about and to the east of the Tuamotu Islands and were well above average south of the Cook Islands. A tongue of cooler equatorial waters remains off the South American coast, still enhancing the cooler east – warmer west temperature gradient. However, these anomalies are generally weak and are expected to stay in the neutral range for several more months. There are indications of a gradual evolution towards weak warm ENSO conditions during 2002, in the months following the southern hemisphere wet season. The November Southern Oscillation Index (SOI) averaged +0.6 (because of positive pressure anomalies over Tahiti); the 3-month mean was +0.1, with trade winds remaining slightly enhanced in the central Equatorial Pacific.