Model Outlooks of ENSO Conditions from October 2009

Product Code: IDCKGLM000

Models predict that El Niño conditions will persist through summer 2009/10

Summary

As detailed in our ENSO Wrap-up, atmospheric circulation and ocean temperatures in the Pacific over the past month are both indicative of a continuing El Niño event.

Most climate model simulations are currently predicting that El Niño conditions will persist throughout the southern hemisphere summer.

POAMA, NCEP CFS and JMA CGCM02 are predicting sea surface temperatures to remain above threshold levels until well into next autumn. The European models (UKMO and ECMWF) show considerably more spread among individual ensemble members, with some runs indicating that a return to neutral conditions in the next three to four months is possible. NASA GMAO is predicting neutral conditions by the end of February 2010. BCC_CGCM continues its Aug-Sep trajectory of neutral conditions.

Model Outlooks

The following table summarizes the opinion of National Climate Centre climatologists regarding the outputs from various 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	1-4 MONTHS (Nov 09 to Feb 10)	4-7 MONTHS (Feb 10 to May 10)
POAMA (run at Bureau of Met)	29 Sep - 28 Oct	Warm	Warm
System 3 ECMWF	01 October	Warm	Warm/Neutral
GloSea * UK Met Office	01 October	Unavailable	Unavailable
CFS NCEP	19 - 28 October	Warm	Warm
CGCMv1 GMAO/NASA	October	Warm	Neutral
BCC_CGCM BCC/CMA	23 - 30 September	Neutral	Neutral
JMA-CGCM02 Japan Met. Agency	September	Warm	Warm #

# Model forecast is run only until the end of April
* 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 the recent warming will be sustained across the Pacific throughout the remainder of the southern year.

While predictability is much lower than for the Pacific Ocean, POAMA continues to predict a neutral Indian Ocean Dipole (IOD) to persist through the outlook period, as is the NASA GMAO model, the other model surveyed here for which IOD forecasts are published.

January 2009

For the 30 runs of POAMA between 29 Sep and 28 Oct 2009, the average NINO3.4 temperature anomaly for JANUARY is +1.53°C and the frequency distribution is as follows:
below −0.83°C: 0% (Cool)
−0.83°C to +0.83°C: 0% (Neutral)
above +0.83°C: 100% (Warm)

April 2010

And similarly for APRIL 2010 the average NINO3.4 index is +1.16°C and the frequency distribution is:
below −0.83°C: 0% (Cool)
−0.83°C to +0.83°C: 0% (Neutral)
above +0.83°C: 100% (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 30 October 2009.
Next update expected late November 2009.