ENSO Updates (2007 thru 2023)

[cycloneye]

The PDO is likely to remain in negative thru the Spring and Summer and that will not allow El Nino to make an appeareance. Here is the Ocean Briefing by CPC that is posted on the 2013 Steering Pattern / Early Indicators thread

Ntxw,what is your take about this?

[Ntxw]

This is quite an informative read from all aspects of weather. Two things I took note one is the continuance of the TAO buoys in the eastern Pacific being somewhat unreliable. It seems they are putting out cooler sub-surface waters compared to GODAS. (Explains the overall trend upwards even through the slight dips since the beginning of the year from the -0.6c)

Secondly is the change from mid-March ENSO plume probabilities went from strongly neutral to a good chance of all three in the early April. That's quite a change for only a few weeks. While I did see you post the data I didn't connect the two until now. It seems the guidance are shying away from neutral confidence the second half of this year. I suppose the PDO call will determine which ENSO event (if any) will take over, but even the PDO in the span of a few weeks have taken a different turn than in March.

[cycloneye]

:uarrow: This is quite an informative read from all aspects of weather. Two things I took note one is the continuance of the TAO buoys in the eastern Pacific being somewhat unreliable. It seems they are putting out cooler sub-surface waters compared to GODAS. (Explains the overall trend upwards even through the slight dips since the beginning of the year from the -0.6c)

Secondly is the change from mid-March ENSO plume probabilities went from strongly neutral to a good chance of all three in the early April. That's quite a change for only a few weeks. While I did see you post the data I didn't connect the two until now. It seems the guidance are shying away from neutral confidence the second half of this year. I suppose the PDO call will determine which ENSO event (if any) will take over, but even the PDO in the span of a few weeks have taken a different turn than in March.

Is there a teconnection between the AO and PDO? If you look at the text of the daily AO,by March 20 it tanks and after that it starts to go up until March 31rst when is almost positive. And is a coincidence that the PDO has warmed during this period.

ftp://ftp.cpc.ncep.noaa.gov/cwlinks/nor ... rent.ascii

[Ntxw]

You may be right cycloneye. The blocking signature is a result of GWO and tropical forcing being +AAM. As it retrograded from the NAO region it developed the -EPO which is a warming feature in the northeast Pacific. Our friend tropicalanalystwx13 made mention of these changes in heights effecting the PDO.

[cycloneye]

Another mixed signal. Here is the ESPI update for April 8 (-0.17). Negative means continuation of Neutral conditions.

http://trmm.gsfc.nasa.gov//trmm_rain/Ev ... y_day.html

[cycloneye]

Nothing new in the Australian update:

http://www.bom.gov.au/climate/enso/

Tropical Pacific remains ENSO neutral

Issued on Tuesday 9 April 2013 | Product Code IDCKGEWWOO

Current atmospheric and oceanic observations show a neutral El Niño-Southern Oscillation (ENSO) state. Model forecasts unanimously show a persistence of this neutral pattern for the remainder of the southern hemisphere autumn and into early winter. In other words, the development of either an El Niño or a La Niña is very unlikely in the coming three months.

Although the neutral ENSO pattern is only having a limited influence on our climate at present, Australia has experienced consistently warm land and sea surface temperatures since spring 2012, including several record breaking heat waves and the warmest summer on record. The persistently warm waters that continue to surround Australia may promote increased local rainfall in favourable weather conditions.

The Indian Ocean Dipole (IOD) has little influence upon Australia’s climate from December through to April. The consensus of current model projections is for a neutral IOD for late autumn into early winter.


Southern Oscillation Index:
The Southern Oscillation Index (SOI) has fluctuated over the past two weeks, with values generally near the +9 or +10 mark. The latest 30-day SOI value to 7 April is +9.0.

Sustained positive values of the SOI above +8 may indicate a La Niña event, while sustained negative values below −8 may indicate an El Niño event. Values of between about +8 and −8 generally indicate neutral conditions.

Trade winds:
Trade winds have strengthened across the western tropical Pacific during the past two weeks and are . The anomaly map for the 5 days ending 7 April shows trade winds are stronger than average across the western Pacific and near average across the remainder of the tropical Pacific.

During La Niña events, there is a sustained strengthening of the trade winds across much of the tropical Pacific, while during El Niño events there is a sustained weakening of the trade winds.

[cycloneye]

Nino 3.4 has cooled once again after being pretty warm for the past couple of weeks. And the tripole looks very good in the Atlantic side.

[cycloneye]

Cool subsurface waters are poised to go up to the surface at Nino 3 and 3.4 areas.

[cycloneye]

Climate Prediction Center 4/15/13 update

Nino 3.4 is on dead neutral at 0.0C.

http://www.cpc.ncep.noaa.gov/products/a ... ts-web.pdf

[Ntxw]

I see no signs from guidance of either direction. No mountain torque event to spark GWO, in turn keeping the MJO in the dead circle. SOI has been more positive than negative but still bouncing around the neutral values. CFSv2 has been going back and forth between warm and cool but still generally averaging neutral.

[cycloneye]

Neutral ENSO is what the majority of the models have for the August/September/October period. Read the discussion below the graphics.





Technical ENSO Update

18 April 2013

Recent and Current Conditions
After a brief period approaching borderline La Niña SST conditions in January and February 2013, the SST anomaly in the Nino3.4 region returned to more clearly neutral levels during March and has remained neutral through mid-April 2013. For March 2013 the Nino3.4 SST anomaly was -0.22 C, indicative of cool-neutral ENSO conditions, and for January-March the anomaly was -0.34 C. Since late 2011, the IRI's definition of El Niño conditions has become the same as that of NOAA/Climate Prediction Center, in which the SST anomaly in the NINO3.4 region (5S-5N; 170W-120W) exceeds 0.5 C. Similarly, for La Niña, the anomaly must be -0.5 C or less. The climatological probabilities for La Niña, neutral, and El Niño conditions vary seasonally, and are shown in a table at the bottom of this page for each 3-month season. The most recent weekly SST anomaly in the NINO3.4 region was 0.0 C, indicating neutral ENSO conditions in the tropical Pacific; this is not far from the -0.22 C level observed in March.

Expected Conditions

What is the outlook for the ENSO status going forward? The most recent official diagnosis and outlook was issued earlier this month in the NOAA/Climate Prediction Center ENSO Diagnostic Discussion, produced jointly by CPC and IRI; it called for a high likelihood of neutral ENSO conditions enduring through the second quarter of 2013, with probabilities of El Niño or La Niña each less than 25% through northern summer 2013. The latest set of model ENSO predictions, from mid-April, is now available in the IRI/CPC ENSO prediction plume, discussed below. Currently, SSTs have been in the middle of the ENSO-neutral range (anomaly of about -0.3 to 0.1 C), and SST is slightly above average in the far western part of the basin. Subsurface temperatures across the equatorial Pacific average close to the climatological average, but are above average in the western quarter of the basin and near average in the east-central tropical Pacific. In the east-central part of the basin, a large pocket of below-average sea temperature at depth is currently overlain by a 50-meter deep layer of near to slightly above average sea temperature, protecting the surface (SST) from the anamalously colder water beneath. In the atmosphere, the basin-wide sea level pressure pattern (e.g. the SOI), has been mainly to slightly above average and the low-level zonal winds have also been near average. Anomalous convection (as measured by OLR) has generally been negative in the central tropical Pacific, and positive in the far western part of the basin. Together, these features collectively reflect ENSO-neutral conditions, and the tendency toward cooler than average ENSO conditions has weakened over the last month.

As of mid-April, 20% of the set of dynamical and statistical models models predicts weak La Niña SST conditions for the Apr-Jun 2013 season, none predicts El Niño conditions, and 80% indicates neutral ENSO. At lead times of 3 or more months into the future, statistical and dynamical models that incorporate information about the ocean's observed subsurface thermal structure generally exhibit higher predictive skill than those that do not. For the Jul-Sep season, among models that do use subsurface temperature information, 85% predicts ENSO-neutral SSTs, 5% predicts El Niño conditions and 10% predicts La Niña conditions. For all model types, the probability for neutral ENSO conditions is 65% or greater from Apr-Jun to the end of the forecast period in northern winter 2013/14. (Note 1). Caution is advised in interpreting the distribution of model predictions as the actual probabilities. At longer leads, the skill of the models degrades, and skill uncertainty must be convolved with the uncertainties from initial conditions and differing model physics, leading to more climatological probabilities in the long-lead ENSO Outlook than might be suggested by the suite of models. Furthermore, the expected skill of one model versus another has not been established using uniform validation procedures, which may cause a difference in the true probability distribution from that taken verbatim from the raw model predictions.

An alternative way to assess the probabilities of the three possible ENSO conditions is more quantitatively precise and less vulnerable to sampling errors than the categorical tallying method used above. This alternative method uses the mean of the predictions of all models on the plume, equally weighted, and constructs a standard error function centered on that mean. The standard error is Gaussian in shape, and has its width determined by an estimate of overall expected model skill for the season of the year and the lead time. Higher skill results in a relatively narrower error distribution, while low skill results in an error distribution with width approaching that of the historical observed distribution. This method shows probabilities for La Niña at 16% for Apr-Jun 2013, 24% for May-Jul, and also 24% for Jun-Aug 2013, remaining between 20% and 25% throughout 2013. Model probabilities for ENSO-neutral conditions are 83% for Apr-Jun 2013, 69% for May-Jul, and 64% for Jun-Aug 2013, decreasing to between 55% and 65% from Jul-Sep through the calendar year. Probabilities for El Niño are 1% for Apr-Jun 2013, 7% for May-Jul, rising to approximately 15% from Jun-Aug through the rest of 2013. In words, the models collectively favor neutral ENSO conditions through to the remainder of 2013; La Niña is very slightly favored over El Niño during all of the period. A plot of the probabilities generated from this most recent IRI/CPC ENSO prediction plume using the multi-model mean and the Gaussian standard error method summarizes the model consensus out to about 10 months into the future. The same cautions mentioned above for the distributional count of model predictions apply to this Gaussian standard error method of inferring probabilities, due to differing model biases and skills. In particular, this approach considers only the mean of the predictions, and not the total range across the models, nor the ensemble range within individual models.

The probabilities derived from the 24 or more models on the IRI/CPC plume describe, on average, maintenance of neutral ENSO conditions during the coming months, continuing through into the second half of 2013. Uncertainty exists, because we are in the period of typically most likely new ENSO event evolution from now until about late June. The model forecast spread expresses that undertainty in the spread between weak La Nina and borderline El Nino conditions, even though the majority of the forecasts is in the neutral range. A caution regarding this latest set of model-based ENSO plume predictions, is that factors such as known specific model biases and recent changes that the models may have missed will be taken into account in the next official outlook to be generated and issued in early January by CPC and IRI, which will include some human judgement in combination with the model guidance.

http://portal.iri.columbia.edu/portal/s ... 2&userID=2

[NDG]

Currently the ECMWF is one the models forecasting Nino 3.4 getting close to a weak El Nino by the heart of the hurricane season but after doing so well a couple of years ago or so the ECMWF has been doing a horrible job with forecasting the ENSO during the past year.
Here are a few examples how warm bias its ensembles mean has been during the past year, in some months even its short range forecast, but who knows, it might be correct this year when I am ignoring it, lol.

[artist]

I asked this in another thread and will ask here as well. There are I feel certain more than just me that has little knowledge as to exactly what this all means. Can someone help us out here?

[cycloneye]

I asked this in another thread and will ask here as well. There are I feel certain more than just me that has little knowledge as to exactly what this all means. Can someone help us out here?

I think I will give you a brief summary of what it has been posted in recent days about ENSO.

1-The majority of the ENSO models forecast Neutral conditions thru the Summer.

2-The waters west of North America are cold meaning PDO continues in Negative which will not allow for El Nino to come anytime soon. (See graphic below)

3-Climate Prediction Center recent updates show no El Nino anytime soon.

[cycloneye]

Currently the ECMWF is one the models forecasting Nino 3.4 getting close to a weak El Nino by the heart of the hurricane season but after doing so well a couple of years ago or so the ECMWF has been doing a horrible job with forecasting the ENSO during the past year.
Here are a few examples how warm bias its ensembles mean has been during the past year, in some months even its short range forecast, but who knows, it might be correct this year when I am ignoring it, lol.

http://www.ecmwf.int/products/forecasts ... !chart.gif
http://www.ecmwf.int/products/forecasts ... !chart.gif
http://www.ecmwf.int/products/forecasts ... !chart.gif

Because ECMWF is doing that forecast,it may be contributing to that April MSLP higher pressures in the Atlantic. Let's see how the May forecast comes.

[artist]

I asked this in another thread and will ask here as well. There are I feel certain more than just me that has little knowledge as to exactly what this all means. Can someone help us out here?

I think I will give you a brief summary of what it has been posted in recent days about ENSO.

1-The majority of the ENSO models forecast Neutral conditions thru the Summer.

2-The waters west of North America are cold meaning PDO continues in Negative which will not allow for El Nino to come anytime soon. (See graphic below)

3-Climate Prediction Center recent updates show no El Nino anytime soon.

thank you cycloneye

[cycloneye]

The Eurosip April update is with a wide range.

[cycloneye]

Climate Prediction Center 4/22/13 update

In essence,anything new from it as Nino 3.4 continues in dead Neutral with the small ups and downs. Todays update is down to -0.1C and that is down from 0.0C that was in last week's update.

http://www.cpc.ncep.noaa.gov/products/a ... ts-web.pdf

[cycloneye]

Australian 4/23/13 update

They are with the same forecast as CPC.

http://www.bom.gov.au/climate/enso/

ENSO neutral state expected to persist well into winter

Issued on Tuesday 23 April 2013 | Product Code IDCKGEWWOO

The tropical Pacific has remained in a neutral El Niño-Southern Oscillation (ENSO) state since mid 2012. Currently, all atmospheric and oceanic indicators of ENSO remain within their neutral range. All climate models surveyed by the Bureau of Meteorology favour ENSO-neutral conditions (neither El Niño nor La Niña) persisting through the southern hemisphere winter.

Southern Oscillation Index:

The Southern Oscillation Index (SOI) has dropped slightly compared to two weeks ago. The latest 30-day SOI value to 21 April is +6.9.

Sustained positive values of the SOI above +8 may indicate a La Niña event, while sustained negative values below −8 may indicate an El Niño event. Values of between about +8 and −8 generally indicate neutral conditions.

Monthly sub-surface:

The four-month sequence of sub-surface temperature anomalies (to 22 April) shows cool anomalies in the sub-surface of the eastern equatorial Pacific; this pool of cooler than normal water peaked in extent in January and has weakened since. The position of this pool of cooler-than-average water has been moving westward over recent months. Much of this water was more than 2 °C cooler than average for April. Warm anomalies remain present in the sub-surface of the far western equatorial Pacific.

Weekly sub-surface:

Compared to two weeks ago, the sub-surface map for the 5 days ending 21 April shows cool anomalies in the subsurface of the eastern Pacific have strengthened; water more than 1 °C cooler than average is present between 50 and 250 m deep across nearly all of the equatorial Pacific. Warm anomalies are still present in the far western equatorial Pacific sub-surface, but have weakened slightly compared to two weeks ago.

Climate Models:

International climate models surveyed by the Bureau indicate that SSTs in the equatorial Pacific Ocean are expected to remain neutral at least through the southern hemisphere winter. Predictions from dynamical models are known to have lower skill during the April to June period, however, all surveyed models are consistent in their outlooks.

[cycloneye]

The ESPI data is at -1.39 which means Neutral conditions continuing with no signs of El Nino.



http://trmm.gsfc.nasa.gov//trmm_rain/Ev ... y_day.html