Climate Model Summary

Updated: Unavailable

Australian climate is influenced by temperature patterns in the Pacific and Indian Oceans. This page provides information on Pacific and Indian Ocean outlooks for the coming six months based on a survey of international climate models. It is updated monthly.


Models suggest El Niño likely by mid-winter

All climate models used in this survey suggest that an El Niño will develop by the southern hemisphere spring, with six of the seven models indicating El Niño thresholds are likely to be exceeded as early as July. Currently, the El Niño-Southern Oscillation (ENSO) is neutral, however, patterns in the tropical Pacific Ocean and atmosphere are consistent with the early stages of a developing El Niño.

El Niño is often, but not always, associated with below-average rainfall during the second half of the year across large parts of southern and inland eastern Australia. Daytime temperatures also tend to be above average over southern Australia.

The Indian Ocean Dipole (IOD) is also neutral. Current model outlooks suggest the IOD will remain neutral throughout the forecast period, however, the chance of a positive IOD event is elevated during El Niño events.

For more details on both ENSO and the IOD, please see the ENSO Wrap-Up.

Average of international model outlooks for NINO3.4

The average NINO3.4 value taken from 7 international models at a three month outlook
The average NINO3.4 value taken from 7 international models at a five month outlook

The arrows on the dials above indicate the combined average of monthly NINO3.4 outlooks from a survey of international global climate models. Note that the individual model runs vary around the average.

More information:

NINO3.4 Outlook

The latest NINO3.4 forecasts (initialised in April) indicate the tropical Pacific is likely to warm over the coming months. Most models indicate El Niño thresholds will be exceeded by July, with two models forecasting a more rapid warming trend, with the ensemble mean reaching +1.2 °C by July, while the UKMO model is predicting a more conservative value of +0.5 °C.

The range in forecast values of NINO3.4 is also evident in individual ensemble members (forecast scenarios) from each model with values ranging between +0.2 °C and +3.0 °C by September. (See the 'Models' tab for links to individual model output for NINO3.4).

The most recent NINO3.4 value is +0.3 °C for the week ending 13 April 2014. Sustained NINO3.4 values above +0.8 °C indicate El Niño.

The following graph shows the average forecast value of NINO3.4 for each international model surveyed for the selected calendar month. If the bars on the graph are approaching or exceeding the blue dashed line, there is an increased risk of La Niña. Similarly, if the bars on the graph are approaching or exceeding the red dashed line, there is an increased chance of El Niño.

NINO3.4 covers the central Pacific region.

NINO3.4 Outlook

Nino 3.4 2 month outlook Models information

Indian Ocean Dipole (IOD)

The IOD index remains neutral with a latest weekly value of –0.3 °C for the week ending 13 April 2014. The IOD typically has little effect on Australian climate during the months from December to April. This is due to the IOD pattern being unable to form once the monsoon trough moves south over the eastern tropical Indian Ocean. Beyond this time outlooks show a neutral IOD. However, the chance of a positive IOD event is elevated during El Niño.

The following graph shows the average forecast value of the IOD index for each international model surveyed for the selected calendar month. If the majority of models are approaching or exceeding the blue dashed line, then there is an increased risk of a negative IOD event. If the majority of models are approaching or exceeding the red dashed line, then there is an increased risk of a positive IOD event.

IOD Outlook

These form controls display per month outlook graphs.

Latest POAMA IOD outlook Models information

Predictive Ocean Atmosphere Model for Australia (POAMA)

POAMA, run at the Bureau of Meteorology, generates an eight-monthly forecast on the first day of each month. The most recent model run (started in April) predicts NINO3.4 is most likely to remain within neutral values through until June, however, over 90% of the POAMA outlook scenarios (ensemble members) exceed El Niño thresholds in September, indicating a high likelihood of El Niño development. The following forecast values (at the top of the table) are for the ensemble mean.

Month 2

NINO3.4 forecast value: Not available

Range Category Frequency distribution
below −0.8 °C: (Cool) Unavailable
−0.8 °C to +0.8 °C: (Neutral) Unavailable
above +0.8 °C: (Warm) Unavailable

Month 4

NINO3.4 forecast value: Not available

Range Category Frequency distribution
below −0.8 °C: (Cool) Unavailable
−0.8 °C to +0.8 °C: (Neutral) Unavailable
above +0.8 °C: (Warm) Unavailable

Month 6

NINO3.4 forecast value: Not available

Range Category Frequency distribution
below −0.8 °C: (Cool) Unavailable
−0.8 °C to +0.8 °C: (Neutral) Unavailable
above +0.8 °C: (Warm) Unavailable

More information:

Model details

The models used within our survey are listed below with links to their agency homepages, model output and technical information about the model.

Agency/Source/Provider Latest
NINO3.4
Latest
IOD
Model Model run used in this survey:
BOM - Bureau of Meteorology View NINO3.4 data
View IOD data POAMA
Unavailable
ECMWF (EU) View NINO3.4 data Not public System4 Unavailable
JMA View NINO3.4 data Unavailable JMA/MRI-CGCM Unavailable
METEO-FRANCE Not public Not public ARPEGE 1 April 2013
NASA - GMAO (USA) View NINO3.4 data
View IOD data GEOS5
1 April 2013
NOAA - NCEP (USA) View NINO3.4 data
Unavailable CFSv2 Unavailable
UKMO View NINO3.4 data Not public GloSea4 Unavailable

Product Code: IDCKGLM000

Next update expected Unavailable

Model data are provided for Bureau of Meteorology use by the agencies detailed in the Models section. Respective agency copyright applies to these data.