Feature article
The Brief La Niña of 2005-06 and the El Niño of 2006-07
Anthony G. Barnston, International Research Institute for Climate and Society (IRI)
Figure 1. Time-longitude section of zonal wind anomaly and SST anomaly
Historically since 1950, ENSO episodes have tended to occur with approximately one-year duration, often beginning near April-July of one year and ending near March-May of the following year. Exceptions have occurred.