Phillip Reid - Antarctic Climate & Ecosystems Cooperative Research Centre (ACE CRC)

Nino (Niño) Regions

To enable analysis of SSTs, primarily for the purposes of examining the state of the ENSO cycle, the equatorial Pacific is divided into five regions called Nino (Niño) 1,2,3,4 and 3.4 which are defined as follows:

• Nino 1: the area bound by 80-90W and 5-10S
• Nino 2: the area bound by 80-90W and 0-5S
• Nino 3: the area bound by 90-150W and 5N-5S
• Nino 4: the area bound by 150W-160E and 5N-5S
• Nino 3.4: the area bound by 120-170W and 5N-5S

These are depicted in the following diagram. Click for a larger image.

Nino indices are based on the average of the SSTs in their respective regions - the indices actually refer to the monthly SST anomalies. SST averages are calculated, usually over a 30 year period and monthly means of SSTs in each of the regions form the indices. See here for an example.

Email me:

p.reid[at]bom.gov.au

Phone me:

(03) 62262983

Mail me:

Phil Reid

ACE CRC

Private Bag 80 Hobart

Tasmania 7001

Australia