SOI Data Files

These files are updated on a regular basis (near daily and monthly) 

Please note: Long Paddock products use Southern Oscillation Index (SOI) data which have been calculated using a climatic base period of 1887 to 1989. The Australian Bureau of Meteorology calculates the SOI using a 1933-1992 base period. We provide SOI data calculated using a 1887-1989 base period because the SOI phase maps are based on these data. SOI data calculated using a 1933-1992 base period are provided for comparison purposes.

The file called 'MonthlySOIPhase1887-1989Base' contains a column of numbers under the heading 'Phase'. The five Phases of the SOI are as follows:

  1. consistently negative
  2. consistently positive
  3. rapidly falling
  4. rapidly rising
  5. consistently near zero


Last updated: 7 May 2019