econintersect.com
       
  

FREE NEWSLETTER: Econintersect sends a nightly newsletter highlighting news events of the day, and providing a summary of new articles posted on the website. Econintersect will not sell or pass your email address to others per our privacy policy. You can cancel this subscription at any time by selecting the unsubscribing link in the footer of each email.



posted on 14 June 2017

JAMSTEC Updates their Nino 3.4 Forecast - JAMSTEC agrees El Nino not Likely

Written by Sig Silber

It could have been a bit more conclusive but as expected JAMSTEC has reduced their estimate for the important Nino 3.4 Index to the point that it no longer signals an El Nino but does suggest that El Nino-like conditions might apply for the heart of the winter. I have reviewed their forecast maps re temperature and precipitation and they seem to agree with their Nino 3.4 forecast - we will cover the forecast maps in detail in our Saturday Special Report where we compare the NOAA and JAMSTEC updated Seasonal Outlooks. 

 weather.caption for Updates


Please share this article - Go to very top of page, right hand side for social media buttons.


This report is mostly a Heads Up that the JAMSTEC forecast has drastically changed and we will soon see the extent to which the previously divergent forecasts have now come closer together. In this Update, we comment on the new JAMSTEC two-year forecast of the NINO 3.4 Index which is the primary (but not only) criteria for concluding which phase of ENSO we should expect.

Here is their new forecast.

June 1, 2017 Nino 3.4 Forecast.

Notice that this new forecast peaks briefly at about 0.7C and seems to be at 0.5C or above from November 2017 through February 2018. Obviously no one expects a forecast to work out exactly as forecast but, as forecast, this event most likely will not meet the U.S. standard for an El Nino which with respect to the Nino 3.4 Index component would require five consecutive three-month periods where the Nino 3.4 average equaled or exceeded 0.5C. We do not have the discussion yet from JAMSTEC. That should follow soon and probably will be available for our report on the seasonal outlooks of the two agencies which we plan to publish Saturday evening.
Are they hinting at a La Nina for the following winter? That is a long way off.

To provide perspective, I am showing the current forecast and the prior three forecasts with the earlier forecasts on the right and the most recent forecast on the left.

June 1, 2007 JAMSTEC Forecast May 1, 2017 JAMSTEC Forecast March 1, 2017 JAMSTEC Forecast January 1, 2017 JAMSTEC Forecast
June 1, 2017 JAMSTEC Nino 3.4 Forecast May 1, 2017 Forecast. March 1, 2017 JAMSTEC Nino 3.4  Forecast January 1, 2017 JAMSTEC Nino 3.4 Forecast

 

As you can see there was a big increase in the forecast for the Nino 3.4 Index between January and March. Then a slight decline from March to May. And now a dramatic reduction.
The images are a bit small so I have also provided a second way of comparing them and here you view from the bottom right which is the January 1 forecast, then in the second row you have the March 1 forecast on the right and the May 1 forecast on the left and finally the image on the top row to the left is the current forecast. This highlights the extreme forecast made dated January 1 and then two more moderate but quite similar forecasts dated March 1 and May 1 and now for June 1 a forecast that resembles the January 1,  forecast.
June 1, 2017 JAMSTEC Nino 3.4  
JAMSTEC Nino 3.4 May 1 2017 JAMSTEC March 1, 2017
 

 

Below is the primary NOAA Nino 3.4 forecast tool.

CFSv2 Forecast as of June 12, 2017

It is not showing an El Nino for Fall and Winter. In fact the temperature anomaly declines after this summer.
Thus both the NOAA and JAMSTEC forecasts are signaling ENSO Neutral but the peak level of the Nino 3.4 Index occurs six months later in the JAMSTEC forecast which would impact monthly temperature and precipitation forecasts. We will learn more about that when NOAA releases their maps tomorrow and when I complete my comparison of those maps which we will publish on Saturday.
But there is a big spread among the various forecast members for both the NOAA and JAMSTEC Nino 3.4 forecasting tools. So there is not a high level of confidence in these forecasts. I am using this NOAA image rather than the image that updates daily because it also shows the sea surface temperature forecast for the entire Equatorial Pacific. Red is a warm anomaly. For an El Nino forecast the model would be showing red along the Equator in the Eastern Pacific and the model is not projecting that. Those images are a bit small I agree. But the Equator is marked and so is the Coast of South America. It is a little tricky but you can find larger images here. Track across the top row labeled SST Normalized with Skill Mask and click on the E3 which is the latest forecast. Each of the images can also be clicked on to enlarge.

NOAA relies a lot on the assessment made by this organization. 

International   Research   Institute   for   Climate  and   Society   (IRI)  was established  in  1996  by  the  U.S.  National  Oceanic  and  Atmospheric  Administration (NOAA)  and  Columbia  University  as  the  world’s  first  international  institute  with a mission to apply climate science in the service of society.

The new IRI/CPC Meteorologist survey issued on June 8 is shown on the left. And the earlier May 18, 2017 fully model-based report is shown on the right. There will be an update tomorrow. New information is released all the time.

June 8, 2017 IRI/CPC ENSO Side by Side Forecasts.

There is a big difference between the perspective on May 18 and June 8. The red (El Nino) bars were higher than the green (ENSO Neutral) bars in the May 18 analysis and now the Neutral green bars dominate. 

Here is the discussion they released with their update.

IRI ENSO Forecast

CPC/IRI ENSO Update

Published: June 8, 2017

El Niño/Southern Oscillation (ENSO) Diagnostic Discussion issued jointly by the Climate Prediction Center/NCEP/NWS and the International Research Institute for Climate and Society

ENSO Alert System Status: Not Active

Synopsis: ENSO-neutral is favored (50 to ~55% chance) through the Northern Hemisphere fall 2017.

During May, ENSO-neutral continued, though sea surface temperatures (SSTs) were above average in the east-central Pacific Ocean . The latest weekly Niño index values were near +0.5°C in most of the Niño regions, except for the easternmost Niño-1+2, which was at +0.2°C. The upper-ocean heat content anomaly increased during May, reflecting the expansion of above-average sub-surface temperatures across the central and eastern Pacific in association with a downwelling oceanic Kelvin wave. While ocean temperatures were elevated, the atmosphere was close to average. Atmospheric convection anomalies were weak over the central tropical Pacific and Maritime Continent, while the lower-level and upper-level winds were near average over most of the tropical Pacific. Both the Southern Oscillation Index (SOI) and Equatorial SOI were also near zero. Overall, the ocean and atmosphere system remains consistent with ENSO-neutral.

Many models predict the onset of El Niño (3-month average Niño-3.4 index at or greater than 0.5°C) during the Northern Hemisphere summer. However, the NCEP CFSv2 and most of the models from the latest runs of the North American Multi-Model Ensemble (NMME) are now favoring the continuation of ENSO-neutral. These predictions, combined with the near-average atmospheric conditions over the Pacific, have resulted in slightly more confidence for the persistence of ENSO-neutral (50 to ~55% chance). However, chances for El Niño remain elevated (35-50%) relative to the long-term average into the fall. In summary, ENSO-neutral is favored (50 to ~55% chance) through the Northern Hemisphere fall 2017 (click CPC/IRI consensus forecast for the chance of each outcome for each 3-month period).

This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration (NOAA), NOAA’s National Weather Service, and their funded institutions. Oceanic and atmospheric conditions are updated weekly on the Climate Prediction Center web site (El Niño/La Niña Current Conditions and Expert Discussions). Forecasts are also updated monthly in the Forecast Forum section of CPC’s Climate Diagnostics Bulletin. Additional perspectives and analysis are also available in an ENSO blog.

The next ENSO Diagnostics Discussion is scheduled for 13 June 2017. [Editor's Note: I believe this report meant to say July 13, 2017]

Here is the most recent Nino 3.4 report from the Australian Bureau of Meteorology (BOM). What is shown here is the latest published run of their proprietary Nino 3.4 forecasting model.

Australia POAMA ENSO model run June 4, 2017

Note their forecast is showing ENSO Neutral through their forecast period. Their forecast is Neutral flirting a bit with La Nina in August. Australian BOM employs a different threshold for considering a SSTA to be either La Nina or El Nino. Most meteorological agencies use plus or minus 0.5C but BOM uses plus or minus 0.7C but that is not a factor in this case.

Atmospheric Confirmation

The NINO 3.4 Index is not suggesting that we will have an El Nino. But recent readings have indicated marginal El Nino conditions. So one would want to see if the atmosphere is confirming El Nino conditions. The most widely used approach is called the Southern Oscillation Index (SOI). Here are the current values of this index.

June 13 SOI Index

This index provides an easy way to assess the location of and the relative strength of the Convection (Low Pressure) and the Subsidence (High Pressure) near the Equator. Experience shows that the extent to which the Atmospheric Air Pressure at Tahiti exceeds the Atmospheric Pressure at Darwin Australia when normalized is substantially correlated with the Precipitation Pattern of the entire World.

SOI = 10 X  [ Pdiff - Pdiffav ]/ SD(Pdiff)  where  Pdiff   =   (average Tahiti MSLP for the month) - (average Darwin MSLP for the month),  Pdiffav   =   long term average of Pdiff for the month in question, and SD(Pdiff)   =   long term standard deviation of Pdiff for the month in question. So really it is comparing the extent to which Tahiti is more cloudy than Darwin,  Australia.  During El Nino we expect Darwin Australia to have lower air pressure and more convection than Tahiti (Negative SOI especially lower than -7 correlates with El Nino Conditions). During La Nina we expect the Warm Pool to be further east resulting in Positive SOI values greater than +7).    

The 30 day average right now is -0.37 and the 90 day average right now is -2.75 so one could hardly have more ENSO Neutral readings

Here is what we said on March 11, 2017

posted on 11 March 2017

Models Predict an El Nino Later this Year - Why that is Implausible.  (Click to read)

Written by Sig Silber

Here is the key graphic and discussion from our March 11 analysis.

Why the Forecast of an El Nino is Implausible

March 4 Upper Equatorial Heat Anomaly Situation

It is very simple really. There is not much warm water in the Western Pacific Warm Pool. The above shows the situation east of Australia. There is also a less intense portion of the Warm Pool further west which is why the entire area is called the Indo-Pacific Warm Pool. the water temperature in the Warm Pool normally exceeds 28C and may be a lot warmer. The water level actually builds up to perhaps two feet higher there than in the Eastern Pacific [Editor's note: (added this evening for clarification) due to the prevailing Easterlies and the expansion of warmer water]. Generally this warming takes a bit of time and right now with the very short recent Cool Event (which NOAA concludes was a La Nina and we disagree) that just ended, there has not been enough time to create a robust Warm Pool. That is the punch line. We believe that the warm water in the Eastern Pacific has tricked the models into forecasting an El Nino. Warm water forming in the East Pacific is the way many El Ninos begin. But without sufficient warm water in the Western Warm Pool, the incipient El Nino is not likely to develop into a true El Nino. It probably will be a Warm Event i.e. ENSO Neutral with ONI between 0 and 0.5C but not reaching or exceeding 0.5C for a sufficiently long duration to be considered an El Nino.

For comparison purposes this is the current version of the above graphic.

June 7, 2017 Equatorial Temperature Anomalies

To facilitate comparison I am bringing the two graphics together one on top of the other.

March 4, 2017 Equatorial Subsurface Temperatures
June 7, 2017 Equatorial Subsurface Temperatures.

 

I have not done the best job of snipping these graphics and getting them lined up exactly but you can see that there is a big difference between the situation in March which to me did not look favorable for El Nino development and the situation now which is even less favorable.
You can see that there is now some subsurface warm water in the area where Nino 3.4 is measured but there is very little warm water to the west of 150W. The currents mostly move from west to east so the future situation is not likely to be one where there is water sufficiently warm to create an El Nino. There is also cooler water at depth. What is showing is anomalies not actual temperatures but the Nino 3.4 index (measurements between 170W and 120W along the Equator including five degrees north and south) is based on deviations from climatology for the particular time of year. Whether that is the best approach given that oceans are warming is a different conversation but it is the current approach and the standard for climatology is adjusted every five years for the Equator. But evaporation is not based on anomalies but on absolute temperatures (humidity is a factor also). But how we measure and predict the phases of ENSO is not the topic this evening but it is an important topic which right now has no easy answer. The above is however fairly convincing to me. And I wonder why JAMSTEC thinks that the Nino 3.4 Index will record 0.5 or higher from November of this year to February of 2018. I personally doubt it.

Focus on the Indo-Pacific Warm Pool

The below is the typical situation of the Indo-Pacific Warm Pool. [Click for Source] This  graphic is not showing temperature anomalies but actual temperatures. The water colored red needs to move to the area between 170W and 120W to have an El Nino. That would shift the precipitation pattern since warm water evaporates more readily than cooler water. That is how ENSO works. it changes the location along and near the Equator where water is evaporating to form clouds and where the precipitation takes place and thus the locations where warm air is subsiding and drying. That pattern at any point in time is called the Walker Circulation. In general, the Walker Circulation differs dramatically for La Nina versus El Nino. I have presented those graphics showing the pattern many times and am not doing so tonight to keep this report at a manageable size.

Western Pacific Warm Pool

I do not want to go into a full discussion of ENSO dynamics this evening but the below graphic explains a lot. You see the prevailing Easterly Trade Winds which slacken off during an El Nino. The Trade Winds skim the warm water off the surface and it accumulates in the Western Pacific and to some extent in the Indian Ocean. The "Thermocline" is pretty interesting. It is the dividing line between the near surface temperature gradient and a steep discontinuity to much cooler water. The angle shown is steeper for La Nina and flatter during ENSO Neutral and may even point downwards during a strong El Nino when warm water accumulates off the coast of Ecuador. Notice the actual elevation of the water in the Western Pacific along the Equator may be as much as a meter higher than off the coast of Ecuador during La Nina. Warm water is less dense and the Easterlies cause water to build up in the Western Pacific. ENSO is like a battery. La Nina charges it. The discharge process is called El Nino. When viewed as a battery it should raise a red flag when an El Nino is projected soon after a very powerful El Nino occurred. The has not been sufficient time for the ENSO battery to recharge. The most recent La Nina was minimal at best.

ENSO Dynamics
More information is available here.

Below is the current situation of the Thermocline in more detail.

June 7, 2017 Equatorial Thermocline

The steepness of the Thermocline is moderate and thus suggestive of ENSO Neutral which is what we have. To sort through what might appear to be a jumble of lines on this graphic, the 20C or the 25C Isotherm lines which connect water of equal temperature (not temperature anomalies) are for many purposes the best way to look at this and they are highlighted on this graphic. The 27C and 28C isotherms where they intersect the surface, suggest where it is warm enough for convection to easily occur.

Conclusion

It is well known that attempting to predict an El Nino prior to June is high risk. And yet meteorological agencies have no choice but to make their best estimate of the probabilities of ENSO Neutral, La Nina, and El Nino.

When most of these agencies forecasted an El Nino earlier this year, it seemed implausible to us and we reported that on March 11. Since then it has been a long wait for the computer models to in our opinion get real. This slowly seems to have happened. Of course the earlier forecasts might turn out to have been correct. What we have now are the current forecasts. Forecasts and actuals are two different things. It is the actuals/observed that count but we will not know that until the Northern Hemisphere winter comes and goes. But for now the models agree with our assessment of what the Equatorial Pacific is telling us.

This means we now will have greater confidence in the seasonal outlooks issued by meteorological agencies as the ENSO forecast is central to their forecasts beyond perhaps 14 days. The phases of the low frequency cycles such as the PDO and AMO and corresponding cycles in the Indian Ocean and the variations of the PDO and AMO in the Southern Hemisphere are also very important but at this point in time not well handled by meteorological agencies or the Climate Change Community.   

Aside from the actual forecasts and how they work, it it is clear to us that the models are not doing a good job of making predictions in the sense that the models have had a low level of agreement with each other and are changing their forecasts rapidly. This is typical of attempts to forecast an El Nino prior to June but the forecasts have been especially variable this year or so it seems. We will not know for sure which forecasts were correct until Winter happens.

There has been talk of the state of the art having advanced to the point where ENSO events could be predicted with reasonable reliability one year in advance and perhaps two years in advance. Recent experience casts doubt on those claims. We will address this issue going forward. It is our belief that the methodology being used for predicting ENSO phases and the impacts on weather are not appropriate. After all, the current methodology dates back to the work of Jacob Bjerknes in the 1960's. New tools are available now and there are new theories that have been developed using Global Climate Models. We do not have to rely on 1960's and earlier theories and measurement technologies.

Some Housekeeping Issues

This report will be posted late Wednesday June 14.  A link to this report will appear in the Weekly Report for reference until the Saturday after the next NOAA Update on June 15, 2017 which we will report on June 17. That is only three  days later but we felt that this information was sufficiently important to publish as soon as we had the new forecast. The data that we publish on Wednesday night (but not some of the technical discussion of the ENSO Cycle) will be integrated into the full report on Saturday night. The Regular Weekly Report will be published on June 19. If you are reading this Update Report and wish to transfer to the Current Weather and Climate Report, Click here for the list of Weather Posts. That link takes you to the archive of all weather articles written by Sig Silber so you can if the new Weekly Weather Report has been published go there or back to an earlier report but please keep in mind that the graphics in earlier reports in some cases auto-update and the text may no longer apply to the graphics shown. Remember, if you leave this page to visit links provided in this article, you can return by hitting your "Back Arrow", usually top left corner of your screen just to the left of the URL box.

Click here for a list of Sig Silber's Weather Posts

>>>>> Scroll down to view and make comments <<<<<<










Make a Comment

Econintersect wants your comments, data and opinion on the articles posted. You can also comment using Facebook directly using he comment block below.




Econintersect Weather








search_box
Print this page or create a PDF file of this page
Print Friendly and PDF


The growing use of ad blocking software is creating a shortfall in covering our fixed expenses. Please consider a donation to Econintersect to allow continuing output of quality and balanced financial and economic news and analysis.







Keep up with economic news using our dynamic economic newspapers with the largest international coverage on the internet
Asia / Pacific
Europe
Middle East / Africa
Americas
USA Government





























 navigate econintersect.com

Blogs

Analysis Blog
News Blog
Investing Blog
Opinion Blog
Precious Metals Blog
Markets Blog
Video of the Day
Weather

Newspapers

Asia / Pacific
Europe
Middle East / Africa
Americas
USA Government
     

RSS Feeds / Social Media

Combined Econintersect Feed
Google+
Facebook
Twitter
Digg

Free Newsletter

Marketplace - Books & More

Economic Forecast

Content Contribution

Contact

About

  Top Economics Site

Investing.com Contributor TalkMarkets Contributor Finance Blogs Free PageRank Checker Active Search Results Google+

This Web Page by Steven Hansen ---- Copyright 2010 - 2017 Econintersect LLC - all rights reserved