Climate Model Summary

Climate Model Summary Archive: 25 July 2012

Issued on Wednesday 25 July 2012 |

El Niño remains likely in 2012

Summary

After a brief easing of the warming trend towards El Niño thresholds over the last few months (as detailed in the ENSO Wrap-Up), some further warming of sea surface temperatures in the tropical Pacific has taken place in the past fortnight.

All dynamical models surveyed by the Bureau of Meteorology suggest that sea surface temperatures in the tropical Pacific will continue to warm, approaching or exceeding El Niño thresholds sometime after mid-winter 2012. However, results from individual models continue to show a moderate to high level of spread in their forecasts, meaning there continues to be a range of potential scenarios. Some models surveyed have eased their outlooks slightly since last month, suggesting weaker or later-forming El Niño conditions. Climatologists will continue to monitor conditions and outlooks closely for any further developments over the coming months.

Model Outlooks

The following table summarises the opinion of National Climate Centre (NCC) climatologists regarding the outputs from various long range forecast models. The model set contains seven 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.

MODEL /
GROUP
Forecast Start Date 1-3 MONTHS
(Aug 2012 to Oct 2012)
4-6 MONTHS
(Nov 2012 to Jan 2013)
POAMA
Australian Bureau of Meteorology
1 July Neutral/Warm Neutral/Warm
CFS
NCEP (US)
23 July Neutral/Warm Warm
GEOS-5
NASA Goddard GMAO (US)
1 July Warm Warm
System 4
ECMWF (EU)
1 July Neutral/Warm Warm
JMA/MRI-CGCM
Japan Met. Agency
1 July Warm Warm
GloSea
UK Met Office
1 July Warm Warm #
ARPEGE*
MeteoFrance
1 July Neutral/Warm Neutral/Warm

# Forecast is for November and December only.
* This model has been introduced to our Model Summary as of 16 May 2012. A password is required to view these forecasts.

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 on day 1 of each month for the following eight months. The most recent model run predicts NINO3.4 will continue to warm over the next few months, approaching the El Niño threshold in August-September. POAMA suggests NINO3.4 will then remain near the +0.8 threshold until the end of the austral summer.

The IOD index remains neutral with the most recent value of 0.2 for the week ending 22nd July. Recent forecasts from the POAMA model predict the IOD will remain neutral during the austral winter and spring.

September 2012

The most recent POAMA model run (1 July) predicts the average NINO3.4 temperature anomaly for September 2012 will be +0.8 °C and the frequency distribution is as follows:
below −0.8 °C: 0.0% (Cool)
−0.8 °C to +0.8 °C: 43.3% (Neutral)
above +0.8 °C: 56.7% (Warm)

December 2012

For December 2012, the average NINO3.4 temperature anomaly is +0.8 °C and the frequency distribution is as follows:
below −0.8 °C: 0.0% (Cool)
−0.8 °C to +0.8 °C: 50.0% (Neutral)
above +0.8 °C: 50.0% (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 on the 25th of July 2012.
Next update expected 8th of August 2012.


See also the ENSO Wrap-up archive here.

Past climate model summaries