Climate Model Summary

Climate Model Summary Archive: 29 September 2010

Models predict La Niña event to continue through 2010


As detailed in the ENSO Wrap-up, a La Niña event is well established in the Pacific Ocean.

Dynamical models surveyed by the Bureau of Meteorology suggest central Pacific Ocean (Niño3.4) sea surface temperatures will remain at levels typical of a La Niña event through 2010, with the majority of the models indicating the event will persist well into the first quarter of 2011.

The ECMWF, UK Met Office, NCEP and NASA models predict Niño3.4 will cool further, with the UK Met Office, NCEP and NASA models predicting Nino3.4 will reach its coolest temperatures towards the end of 2010. The remaining models suggest central Pacific Ocean temperature differences from normal will remain at current levels, with the only exception being the KMA-SNU model, which predicts Nino3.4 to start warming through the southern hemisphere spring.

The Bureau's POAMA model suggests that ocean temperatures will remain at La Niña levels at least into the first quarter of 2011.

Model Outlooks

The following table summarises the opinion of National Climate Centre climatologists regarding the outputs from various long range forecast models. The model set contains eight reputable ocean or coupled ocean/atmosphere climate models that take into account complex physical ocean processes. NCC's interpretation may not necessarily be the same as the organisations producing the model output. You are therefore encouraged to follow the hyperlinks to the various institutions listed in the table.

See About ENSO outlooks for details on the models and a summary of the terms used.

Forecast Start Date 1-3 MONTHS
(Oct 10 to Dec 10)
(Jan 10 to Mar 11)
Australian Bureau of Meteorology
27 September Cool Cool
System 3
1 September Cool Cool
GloSea *
UK Met Office
1 September Cool Cool #
28 September Cool Cool
NASA Goddard GMAO (US)
1 September Cool Cool/Neutral
Japan Met. Agency
1 September Cool Neutral/Cool
Korean Met. Administration
September Cool/Neutral Neutral/Cool
BCC/CMA (China)
Unavailable Unavailable Unavailable

# Model forecast is run only until the end of February
* Note that this page requires a password, freely available from UK Met Office
Note that some links above may be updated to more recent forecasts than listed here.

POAMA Forecasts

The POAMA model, run at the Bureau of Meteorology, generates a new forecast every day for the following eight months starting with the latest observations. The average of the most recent 30 model runs predicts La Niña conditions to last into the first quarter of 2011.

A negative IOD event is also underway in the Indian Ocean. The latest weekly value of the IOD index is -0.98. POAMA predicts that the IOD index will remain at negative IOD levels throughout the southern hemisphere spring, before decaying in November and December with the onset of the Australian monsoon.

January 2011

For the 30 runs of POAMA between 29 August 2010 and 27 September 2010, the average NINO3.4 temperature anomaly for January 2011 is -1.37°C and the frequency distribution is as follows:
below −0.8°C: 96.7% (Cool)
−0.8°C to +0.8°C: 3.3% (Neutral)
above +0.8°C: 0.0% (Warm)

March 2011

Similarly for March 2011 the average NINO3.4 index is -0.98°C and the frequency distribution is:
below −0.8°C: 63.3% (Cool)
−0.8°C to +0.8°C: 36.7% (Neutral)
above +0.8°C: 0.0% (Warm)

Similar data for other months can be accessed by following the "POAMA" link in the table above.

Users should exercise caution when interpreting these forecasts and are encouraged to view the actual model outputs by following the web links. Frequent updates of the latest observational data with relevant commentary are available on the Bureau's ENSO Wrap-Up page.

This survey last updated 29th September 2010.
Next update expected 13th October 2010.

See also the ENSO Wrap-up archive here.

Past climate model summaries