Climate Model Summary

Climate Model Summary Archive: 27 April 2011

Models predict neutral conditions by southern hemisphere winter

Summary

As detailed in the ENSO Wrap-up, La Niña conditions continue to weaken in the tropical Pacific, with a forecast return to neutral conditions by the southern hemisphere winter.

Most dynamical models surveyed by the Bureau of Meteorology indicate a continued warming of the equatorial Pacific Ocean temperatures during the coming months with the rate of warming varying between models. Observed sea surface temperatures (e.g., NINO3.4) continue to approach 'neutral' values, with the majority of models predicting neutral conditions by the southern winter, 2011.

The Bureau's POAMA model suggests that central Pacific Ocean temperatures will continue to warm through the autumn and winter months, with the average of all thirty POAMA forecasts favouring neutral conditions throughout winter.

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 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.

MODEL / GROUP	Forecast Start Date	1-3 MONTHS (May 11 to Jul 11)	4-6 MONTHS (Aug 11 to Oct 11)
POAMA Australian Bureau of Meteorology	11 April	Neutral	Neutral/Warm
System 3 ECMWF (EU)	1 March	Cool/Neutral	Neutral
GloSea * UK Met Office	1 March	Cool/Neutral	Neutral/Warm #
CFS NCEP (US)	11 April	Neutral	Neutral
CGCMv1 NASA Goddard GMAO (US)	1 April	Neutral/Warm	Warm
JMA-CGCM02 Japan Met. Agency	15 March	Neutral/Warm	Warm/Neutral
KMA-SNU Korean Met. Administration	1 March	Cool/Neutral	Neutral^
BCC_CMA BCC/CMA (China)	Unavailable	Unavailable	Unavailable

# Model forecast is run only until mid-August
^Model forecast is based on 1 March 2011 run and should be viewed with this consideration - updated forecasts are likely during the next fortnight

* 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 predict neutral conditions to persist through winter, with NINO3.4 predicted to continue its warming trend, but remain within neutral parameters.

The IOD is currently neutral with the latest weekly value of the IOD index at −0.08. POAMA predicts that the IOD index will remain neutral through the southern hemisphere autumn and winter seasons.

June 2011

For the 30 runs of POAMA between 13 March 2011 and 11 April 2011, the average NINO3.4 temperature anomaly for April 2011 is 0.29°C and the frequency distribution is as follows:
below −0.8°C: 0.0% (Cool)
−0.8°C to +0.8°C: 100.0% (Neutral)
above +0.8°C: 0.0% (Warm)

September 2011

For September 2011 the average NINO3.4 index is slightly warmer at 0.78°C and the frequency distribution is:
below −0.8°C: 0.0% (Cool)
−0.8°C to +0.8°C: 46.7% (Neutral)
above +0.8°C: 53.3% (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 30th March 2011.
Next update expected 27th April 2011.

Past climate model summaries

October 2015 El Niño to peak towards end of 2015; rapid decay likely in first quarter of 2016
September 2015 El Niño set to persist at strongest values since 1997-98
August 2015 Models maintain El Niño into 2016
July 2015 El Niño likely to strengthen and persist through 2015
June 2015 El Niño likely to strengthen during spring.
May 2015 Models indicate tropical Pacific to remain well above El Niño thresholds.
April 2015 Models maintain outlooks for El Niño through winter and spring.
March 2015 Model consensus indicates El Niño by winter 2015.
February 2015 ENSO neutral, though tropical Pacific Ocean likely to remain warm.
January 2015 Models suggesting neutral for now, but remaining warm.
December 2014 Tropical Pacific Ocean likely to remain near El Niño thresholds over summer.
November 2014 Models near El Niño thresholds.
October 2014 Models ease outlooks for El Niño in summer.
September 2014 El Niño remains on hold.
August 2014 Models ease their El Niño outlook for spring.
July 2014 Majority of models still favour spring El Niño.
June 2014 El Niño remains likely for 2014.
May 2014 El Niño remains likely for 2014.
April 2014 Models suggest El Niño likely by mid-winter.
March 2014 An increased chance of El Niño from winter.
February 2014 Models indicate tropical Pacific to warm.
January 2014 Models suggest tropical Pacific likely to warm over coming months.
December 2013 Neutral ENSO through summer.
November 2013 Neutral ENSO through summer.
October 2013 Neutral ENSO for austral summer.
September 2013 ENSO and IOD neutral.
August 2013 ENSO neutral; negative IOD weakening.
July 2013 ENSO remains neutral; negative IOD likely
June 2013 Negative IOD, but ENSO remains neutral.
May 2013 Neutral ENSO, possible negative IOD development.
April 2013 Neutral ENSO conditions expected to persist.
March 2013 ENSO neutral set to continue.
February 2013 Models predict neutral conditions to continue.
19 September 2012 Pacific remains close to El Niño thresholds.
5 September 2012 Borderline El Niño conditions continue.
22 August 2012 El Niño remains likely for 2012.
8 August 2012 Models predict weak El Niño in 2012.
25 July 2012 El Niño remains likely in 2012.
11 July 2012 Models suggest increased risk of El Niño in 2012.
27 June 2012 Models suggest further warming through winter.
13 June 2012 Models suggest further warming through winter.
30 May 2012 Neutral in tropical Pacific, but further warming likely.
16 May 2012 Warming in tropical Pacific set to continue.
2 May 2012 Neutral conditions, but warming in tropical Pacific continues.
18 April 2012 Continued warming in tropical Pacific Ocean.
4 April 2012 La Niña ends; conditions neutral.
26 October 2011 La Niña re-established in the Pacific.
27 April 2011 Models predict neutral conditions by southern hemisphere winter.
30 March 2011 Models predict continued weakening of La Niña conditions.
2 March 2011 Models predict continued weakening of La Niña conditions.
2 February 2011 Models predict La Niña will persist into the southern hemisphere autumn.
18 January 2011 Models predict La Niña event will persist through southern hemisphere summer.
8 November 2010 Models predict La Niña event will persist into first quarter of 2011.
27 October 2010 Models predict La Niña event will persist into at least early 2011.
13 October 2010 Models predict La Niña event likely to continue until at least early 2011.
29 September 2010 Models predict La Niña event to continue through 2010.
15 September 2010 Models predict La Niña conditions to continue: La Niña intensifies in the Pacific.
1 September 2010 Models predict conditions to remain above La Niña thresholds: La Niña strengthens in the Pacific.
18 August 2010 Models predict continued cooling in the tropical Pacific: La Niña conditions persist in the Pacific.
31 May 2010 Models predict neutral conditions to persist over coming months, with the possibility of cool conditions later in the year.
April 2010 Models predict neutral conditions to persist over coming months, with the possibility of cool conditions later in the year.
March 2010 Models predict neutral conditions to return to the Pacific by June 2010.
November 2009 Models predict that El Niño conditions will persist through summer 2009/10.