ENSO and Sea Surface Temperatures
El Niño fading and likely to return to neutral state by late autumn of 2003
Equatorial Pacific SSTs weakened during January
The El Niño event has peaked and is waning. There was noticeable cooling of SSTs off the South American coast during the month.
The NINO3 SST anomaly was weaker in January than in December (now +1.1°C), while NINO4 was constant at +1.3°C. Three month (November to January) means are about +1.5°C and 1.4°C for NINO3 and NINO4, respectively. Westerly zonal wind anomalies have reduced in horizontal extent to a region near the dateline, where SST anomalies remain around +2°C and convection remains strongly enhanced. The area of suppressed convection in the west still affects eastern and central Australia, the Coral Sea and the north Tasman Sea.
Equatorial subsurface temperature anomalies have weakened east of the dateline, to be no more than +2°C across the eastern Pacific mixed layer.
Half of the Global Climate Models indicate a warm El Niño event into mid-autumn, with return to neutral conditions by late autumn.