2014 El Nino?

[AbruptSLR]

The following linked MJO report was issued by the Australian BoM on March 11 2014, and notes that the MJO is current absent from the Pacific, and will be absent from the Pacific for at least the next week (this is in keeping with the figure that I posted in reply #198).  After that one of their projections has the MJO weakening, while another has is remaining moderately strong; so we will need to wait and see whether the MJO reinforces the EKW (Equatorial Kelvin wave) between March 17 and 24, or not:

http://www.bom.gov.au/climate/tropnote/tropnote.shtml


"Issued on Tuesday 11 March 2014
Madden-Julian Oscillation in western hemisphere
The Madden-Julian Oscillation (MJO) has progressed into the western hemisphere. The past week has seen active tropical weather over South America while convection remained generally suppressed over the tropical Indian Ocean. When the MJO is over the western hemisphere at this time of year it usually contributes to a break period in the North Australian Monsoon, with higher than normal pressure often observed over the equatorial Indian Ocean and the Maritime Continent including northern Australia.
Despite the MJO contributing to conditions that are unfavourable for large-scale tropical convection over northern Australia, a weak monsoon trough has remained to the north of Australia, over the Coral Sea and the Southwest Pacific during the week. Three tropical cyclones have also developed across these regions: tropical cyclone Hadi currently in the Coral Sea; tropical cyclone Gillian that has now weakened and is situated in the Gulf of Carpentaria; and, tropical cyclone Lusi near Vanuatu. A westward moving, large-scale tropical wave (an Equatorial Rossby wave) has also been active in Australian and far west south Pacific longitudes and is likely to have enhanced tropical cyclone development in these regions.
The MJO is forecast to continue in an eastward progression with some forecast models weakening the MJO by early next week while others maintain a moderate strength for at least the next two weeks. With exception to the hazardous weather in the vicinity of the tropical lows around the far north of Australia and the South Pacific, the rest of the Asia-Pacific tropics are likely to see suppressed convective conditions for the rest of this week and possibly up to two weeks, depending on the strength of the MJO influence."

[AbruptSLR]

The first image from earth wind map for March 12 2014 shows that Tropical Cyclone Lusi is gaining strength and maintaining strong westerlies south of the equator up to at least the dateline.

The second image is from the Albany University vorticity & wind projection for March 20 2014, and indicates increase tropical storm activity that strengthens the westerlies south of the equator and extends them eastward to at least 170W.

It the forecast for a moderately strong MJO actually occurs between March 17 and 25, then the combination of strong westerlies and MJO reinforcement, might be sufficient to start an El Nino event (assuming that the Kelvin wave [EKW] has begun warming SST conditions in the Eastern Equatorial Pacific by that time.

[AbruptSLR]

The attached three images of a MJO forecast has the MJO moving from the Western Pacific eastward from March 17 thru March 26.  We will see if this forecast holds.

[AbruptSLR]

As the BoM report indicated the next few days will have somewhat less active tropical storm activity as supported by the following Cyclocane report:

" SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
   A. TROPICAL CYCLONE SUMMARY:
      (1) AT 121800Z, TROPICAL CYCLONE 18P (LUSI) WAS LOCATED NEAR
20.6S 173.4E, APPROXIMATELY 418 NM EAST OF NOUMEA, NEW CALEDONIA,
AND HAD TRACKED SOUTHEASTWARD AT 13 KNOTS OVER THE PAST SIX HOURS.
MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 70 KNOTS GUSTING
TO 85 KNOTS. SEE REF A (WTPS31 PGTW 122100) FOR FURTHER DETAILS.
      (2) NO OTHER TROPICAL CYCLONES.
   B. TROPICAL DISTURBANCE SUMMARY:
      (1) THE AREA OF CONVECTION (THE REMNANTS OF TC 17P) PREVIOUSLY
LOCATED NEAR 16.0S 141.1E, IS NOW LOCATED NEAR 14.8S 138.0E,
APPROXIMATELY 165 NM SOUTH-SOUTHEAST OF GOVE AIRPORT, AUSTRALIA.
ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A COMPACT, ALBEIT
CONSOLIDATING, LOW LEVEL CIRCULATION CENTER WITH PERSISTENT
CONVECTION ALONG THE SOUTHERN PERIPHERIES. A 130015Z AMSU-B
MICROWAVE IMAGE REVEALS THE CONVECTIVE ORGANIZATION OF THE SYSTEM
HAS REMAINED MINIMAL ALTHOUGH THE LLCC IS BEGINNING TO BECOME MORE
DEFINED. UPPER LEVEL ANALYSIS REVEALS A MARGINAL ENVIRONMENT AS
MODERATE (15 TO 20 KNOTS) VERTICAL WIND SHEAR IS OFFSETTING FAIR
EASTERLY OUTFLOW. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT
20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR
1003 MB. DUE TO THE RECENT CONSOLIDATION, THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO MEDIUM.
      (2) THE AREA OF CONVECTION (THE REMNANTS OF TC 19P) PREVIOUSLY
LOCATED NEAR 15.1S 156.1E, IS NOW LOCATED NEAR 13.2S 163.4E,
APPROXIMATELY 575 NM NORTH-NORTHWEST OF NOUMEA, NEW CALEDONIA.
ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS AN ELONGATED AND
ILL-DEFINED, LOW-LEVEL CIRCULATION CENTER (LLCC) WITH FLARING AND
DISORGANIZED CONVECTION. A 120424Z SSMI IMAGE REVEALS A DISORGANIZED
STRUCTURE AS THE LLCC HAS BECOME VERY POORLY DEFINED. UPPER-LEVEL
ANALYSIS INDICATES A MARGINAL ENVIRONMENT WITH MODERATE TO STRONG
(20 TO 30 KNOTS) VERTICAL WIND SHEAR AND LIMITED OUTFLOW.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1005 MB. THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS REMAINS LOW."

[AbruptSLR]

While the tropical storm activity appears to be diminishing, the attached earth wind map from March 13 2014 shows that between 5N & 5S the trade winds are also diminishing across the length of the equator.

[AbruptSLR]

Washington University (see the following link) shows that the PDO increased from 0.30 in January 2014 to 0.38 in February 2014.  This clearly increases the chances of an early El Nino this Spring:

http://www.jisao.washington.edu/pdo/PDO.latest

[crandles]

Meanwhile, the ensemble mean at
http://www.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/imagesInd3/nino34Sea.gif
isn't getting to weak el nino 0.5 level until October.

using data to 8 Feb:
http://www.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/imagesInd1/nino34Sea.gif
it was getting there as early as May.

suggesting quite a bit longer in neutral territory.

With a Spring/May barrier to forecasting such swings are possible and could of course swing back again... or not....or ....

Think that post of 2 March managed to get just about the bottom of the swing of model projections. Now mean is rapidly climbing past 0.5 in May
compare

and


that would seem to bring the models back more in line with high likelihoods of an El Nino being talked about here.

[deep octopus]

Signs of warm PDO are clear in the NOAA/NESDIS SST anomaly charts:



A streak of warm water (by my estimate, about 1.5 to 2 C above average) is flanking the Pacific coastline of the Americas, separating the cooler waters to the west. In fact—and I think ASLR pointed this out before—but it does seem that this line of warmth is continuous from Alaska down to Ecuador, in part explaining the transition to a much warmer eastern Pacific than we saw a month or so ago. This does not have to do with the Kelvin wave, which is still below the surface.

PDO at +0.38 would make it the highest on that index since May 2010, about the end of the last El Niño. Looks as though March's PDO is going to be even higher.

[AbruptSLR]

crandles, thanks for the CFSv2 forecast update.

deep octopus, thanks for the NESDISS SST anomaly chart.

The following PDO numbers below, indicate that at 0.38 in February we are ahead of the 1997 Super El Nino start, and looking at the SST anomaly I guess that March will exceed the corresponding 1997 PDO value of 0.65:

YEAR     JAN    FEB    MAR    APR    MAY    JUN    JUL    AUG   SEP   OCT   NOV   DEC
1997     0.23   0.28   0.65   1.05   1.83   2.76   2.35   2.79   2.19   1.61   1.12   0.67

It is my opinion that the 2014-15 Super El Nino will be worst that the 1997-98 El Nino, in particular the warm water volume, wwv, is of deep concern to me, as is the MJO forecast (see how the attached image puts the MJO by the dateline by March 27th, and heading East after that); which to me indicates that it is possible that the NINO3.4 could pass 0.5 by the first week in April. 

I am also concerned that there will be a lot of Super Typhoons this coming typhoon season; which, contributes to my belief that the 2014-15 Super El Nino will be the worst on record.

[AbruptSLR]

For those who are uncertain how the NOAA/NESDIS SST anomaly chart, that deep octopus posted in reply #207, relates to the PDO index,  the first attached image shows a typical positive (warm) PDO with a horseshoe SST shape in the North Pacific, just as DO posted; while the second attached image shows a negative (cold) PDO pattern:

[wili]

Are those Kelvin-Helmholtz waves in the mid-Pacific? Is that common?

[Bruce Steele]

Wili, If you are looking at the region just above Hawaii that is the easterlies (at 30 degrees north) causing mixing of surface waters. If you are looking at the gyres along the equator they are normal and caused by the predominate westerlies and upwelling mixing water masses. The warm water being driven by the Kelvin waves haven't reached this far east yet so I don't think you are looking at Kelvin wave effects in that region yet.
 Here is a graphic that describes the eddies along the equator in satellite SST map you linked.
 http://tornado.sfsu.edu/geosciences/classes/m302/easterlies/trades.html
I am no expert at this so if someone else wants to take a shot at this I'm up for criticism.

[wili]

Thanks, Bruce. I did mean the pattern near the equator. I would think that this pattern would have more to do with different kinds of ocean water moving past each other, but maybe it is the result of the winds you describe.

Note that Kelvin-Helmholtz is different than just Kelvin waves (that Kelvin was a busy boy, apparently!). Look at the link I provided--they occur where fluids of different density move past each other (if I understand correctly).

[AbruptSLR]

Here are forecasts about the MJO through March 28 2014, showing that the MJO will enter the Western Equatorial Pacific by March 16, and will enter the Eastern Equatorial Pacific by about March 26 2014.

[AbruptSLR]

The attached images shows the JASON measured sea surface elevation anomaly between March 4 and 14, 2014; which indicates that the leading edge of the Kelvin wave (EKW) was past 140W sometime between March 4 & March 14.  Therefore, it appears to me that there is a good chance that the EKW may have sufficiently warmed the Eastern Equatorial Pacific towards the end of March 2014, so as to assist the MJO (forecast to be in the Eastern Equatorial Pacific in that timeframe) to possibly transition the Walker Circulation Cell into an El Nino configuration:

[JimD]

ASLR

I found this and wanted to bring it to your attention as I think you will find it of great interest.

http://www.sciencemag.org/content/343/6171/641

Abstract

Periodic behavior in the climate system has important implications not only for weather prediction but also for understanding and interpreting the physical processes that drive climate variability. Here we demonstrate that the large-scale Southern Hemisphere atmospheric circulation exhibits marked periodicity on time scales of approximately 20 to 30 days. The periodicity is tied to the Southern Hemisphere baroclinic annular mode and emerges in hemispheric-scale averages of the eddy fluxes of heat, the eddy kinetic energy, and precipitation. Observational and theoretical analyses suggest that the oscillation results from feedbacks between the extratropical baroclinicity, the wave fluxes of heat, and radiative damping. The oscillation plays a potentially profound role in driving large-scale climate variability throughout much of the mid-latitude Southern Hemisphere.

[AbruptSLR]

JimD,

Thanks (I will re-post this in the Antarctic folder for those who do not look here).  This raises the question of how much the extratropical energy from a Super El Nino will effect the Southern Annular Mode (SAM) and consequently ice mass loss from Antarctica.

Best,
ASLR

[wili]

Oops, I see I didn't link the article and video on KH waves in the above post as I claimed. Here it is:


https://andyrussell.wordpress.com/2010/01/

[AbruptSLR]

I believe that the last image of NOAA's Equatorial Subsurface Temperature Anomaly profile was from March 4 (posted by deep octopus), while the attached is from March 9 2014, and that on that date the Kelvin wave (EKW) was about to resurface around 120W.  This implies to me that there is an excellent chance that the projected MJO in the Eastern Pacific (circa March 26-30) will encounter equatorial SSTs that will assist the MJO to disrupt the normal Walker Cell into an El Nino pattern.

[deep octopus]

Within a 2-3 weeks, the Kelvin wave should surface around the eastern Pacific. At this point, another positive feedback of El Niño kicks in, as surface warmth more significantly impacts trade winds in the lower atmosphere in the central Pacific. The bridge of cool water between the surface warmth around the dateline and that of a warm pool forming around Ecuador will close, and the Pacific basin becomes much warmer than average. Evidently, the Kelvin wave's next move (as the months press on) would be for the warm water to break out of the west-to-east motion at the Ecuadorian coast, and drift northward (north of the equator) and southward (south of the equator). This is what gives El Niño a peculiar "cone" or "conical" shape. Meanwhile, the MJO activity would likely sustain the momentum that is seeming to take hold.

I now believe El Niño conditions will begin by mid-April. It would be the earliest formation of one since 1997.



EDIT: Whoops, ASLR has posted essentially the same thing to effect as I was typing. My fault. I will let this post stand for now, if nothing but as a show of agreement.

[CraigsIsland]

"Consensus" is a good thing! Excellent reporting everyone

[AbruptSLR]

I also provide the following link to a report that states that the monsoon trough is now extending into the Eastern Pacific (which can also contribute to a disruption of the normal Walker Cell pattern into an El Nino pattern):

http://www.nhc.noaa.gov/text/refresh/MIATWDEP+shtml/100249_MIATWDEP.shtml

[deep octopus]

NOAA's collaboration of CFS models yields these expectations for April and May SSTs. Formation of El Niño around April is supported by the bridging of two warm pools (the one that has moved eastward from the dateline and has been the center of much storm activity, whereas the newly-formed Ecuadorian warm pool gets a shot of heat from the Kelvin wave that is about to surface.

[AbruptSLR]

While less definitive that the information that deep octopus just posted (from NOAA), the attached Cyclocane 48-hr forcast do show an area of increased tropical storm activity near 15S & 160E; which supports the point that the monsoon trough has extended into the Eastern Pacific; and raises the possibility that this disturbed air could form a tropical cyclone in this area in the next few days (which could give the Kelvin wave another boost from a wwb).

I would also like to note that the horseshoe pattern shown in both the April and the May 2014 CFSv2 month SST anomaly forecast (posted by deep octopus in reply #222) show clear signs that highly positive PDO index values will occur during those months.

[bligh8]

ASLR,

For the last several days I’ve been studying pilot charts for this area of the world, which are representative of historical Ocean & atmospheric data. Ship captains who were tracking weather for creating these charts have accumulated this data. There flawed in two respects in that ship captains avoid areas known to have bad weather for a particular time of year and wind estimates are from an apparent point of view instead of a true or stationary point of view. Yet I found them to be amazingly accurate up to 90 to 95% of the time. I’ve studied these charts for decades and lately I’ve been studying new satellite generated charts of the same type. Historically speaking I can find no anomalies in the trade winds, then again the trades have always been fluky in the Pacific Ocean, right up to the point where one gets 5 to 6 deg off the equator where they steady-up. That said, a two or three knt increase overall in the trade wind speed is nothing to a sailor, where a climate scientist might suggest that it is remarkable. This time of year the charts show a variable wind pattern west of say 170deg West. By that I mean wind speed and direction are varied across the wind rose. Even the tropical cyclones in the areas mentioned are shown to have an 11% probability per month on the charts. (That number 11% represents a high percentage and a place to avoid for a sailor)

The thing that is so disturbing is the large Kelvin wave and all the warm surface water anomalies existing across the Pacific. Behind it all we look at the tremendous heat build up due to agw and it seems that an El-Nino event is surly coming in 2014/2015.

Thanks for your remarks in the Antarctica thread about this.

Best,
Bligh

[Bruce Steele]

I have commented on the biological ramifications of large El Nino's in the California current. The
Humboldt current experiences large swings in the Anchovetta biomass and as a result bird, mammal and fish up the food chain experience stress and population swings.The PDO has a direct effect on salmon stocks , sardine and anchovy populations and these changes are of much longer duration than the effects of the El Nino/La Nina cycles. I would like to better understand what causes the shifts of the PDO as it has consequences for fisheries management. Some fisheries like sardines have temperature triggers in modeling future catch limits and in general the ability to predict when stocks are likely to expand or decline could be advantaged with better predictive abilities. These are fisheries or fisherman centric issues but the effects of large El Nino's also play a huge role in the Asian Monsoon cycle. We don't have commenters from the Indian continent that I am aware of but the failure of Monsoons may have very large ramifications for millions of small farmers in India and if indeed the PDO switches long term back to warm water conditions for the next fifteen to twenty-five years I think the chances of repeated El Nino's ( and drought)increase in comparison to the last fifteen years.
 Thanks everyone for contributing to this thread ! We should have had a poll.   
Size and strength of the? 2014-2015 El Nino and for pure speculation the duration of the +ve PDO 
 

[AbruptSLR]

bligh8,

Thanks for the information about the Pacific winds,

Also, Bruce's information was as interesting as always, and he raised the question of the Pacific cycles (particularly the ENSO and the PDO).  The following is related to the Inter-decadal Pacific Oscillation (which is related to the PDO):

The attached figure of projected changes in surface temperatures in degrees C per decade for hiatus (negative IPO) versus non-hiatus (positive IPO) periods is from Meehl et al (2013).  I am not sure how accurate these projections are but if we have just entered a non-hiatus period, then large parts of the Arctic and the ocean surface immediately offshore of the Amundsen Sea Embayment, ASE, may experience an increase in surface temperature of about 2 degrees C by 2024, above today (although largely these same areas cool by somewhat less than 2 degree C during the following hiatus period, that might begin around 2030)..

Gerald A. Meehl, Aixue Hu, Julie Arblaster, John Fasullo, and Kevin E. Trenberth (2013),"Externally forced and internally generated decadal climate variability associated with the Interdecadal Pacific Oscillation", Journal of Climate 2013 ; e-View doi: http://dx.doi.org/10.1175/JCLI-D-12-00548.1

"Abstract
Globally averaged surface air temperatures in some decades show rapid increases (accelerated warming decades) and in other decades there is no warming trend (hiatus decades). A previous study showed that the net energy imbalance at the top of atmosphere of about 1 Wm-2 is associated with greater increases of deep ocean heat content below 750m during the hiatus decades while there is little globally averaged surface temperature increase or warming in the upper ocean layers. Here we examine processes involved with accelerated warming decades, and address the relative roles of external forcing from increasing greenhouse gases and internally generated decadal climate variability associated with Interdecadal Pacific Oscillation (IPO). Model results from CCSM4 show that accelerated warming decades are characterized by rapid warming of globally averaged surface air temperature and greater increases of heat content in the upper ocean layers and less heat content increase in the deep ocean, opposite to the hiatus decades. In addition to contributions from processes potentially linked to Antarctic Bottom Water (AABW) formation and the Atlantic Meridional Overturning Circulation (AMOC), the positive phase of the IPO, adding to the response to external forcing, is usually associated with accelerated warming decades. Conversely, hiatus decades typically occur with the negative phase of the IPO, when warming from the external forcing is overwhelmed by internally generated cooling in the tropical Pacific. Internally generated hiatus periods of up to 15 years with zero global warming trend are present in the future climate simulations. This suggests that there is a chance the current observed hiatus could extend for several more years."

[AbruptSLR]

In my last post I cited IPO related projected changes in regional surface temperature patterns, and in this post I cite projected changes in precipitation patterns (focused on RCP 8.5):

The linked reference (with a free access pdf) finds that: "Computer model projections of future conditions analyzed by the Scripps team indicate that regions such as the Amazon, Central America, Indonesia and all Mediterranean climate regions around the world will likely see the greatest increase in the number of “dry days” per year, going without rain for as many as 30 days more every year. California, with its Mediterranean climate, is likely to have five to 10 more dry days per year."

The attached image has the following caption:
CMIP5 multi-model ensemble average mean change in frequency of dry days (days/year) by 2060–2089, relative to the historical period 1960–1989, using the RCP8.5 forcing scenario. Stippling indicates areas where at least 70% of the models agree on the sign of the change. Graph to the right: zonal means values. Map was produced using NCAR Command Language; Courtesy of Scientific Reports

The attached image essentially shows the mean change in regional precipitation patterns circa 2075 following our current BAU pathway.  I find it particularly disturbing that this pattern is very similar to the projected pattern for a Super El Nino event, which means that in the future when a Super El Nino event is superimposed on such a mean precipitation pattern, our tropical rain forests (and the Mediterranean climates around the world, including California) will be severely damaged which will both release more CO₂, and will decrease CO₂ absorption, to/from the atmosphere, respectively:

Suraj D. Polade, David W. Pierce, Daniel R. Cayan, Alexander Gershunov & Michael D. Dettinger, (2014),  "The key role of dry days in changing regional climate and precipitation regimes", Scientific Reports, 4, Article number: 4364, doi:10.1038/srep04364

http://www.nature.com/srep/2014/140313/srep04364/full/srep04364.html

Abstract: "Future changes in the number of dry days per year can either reinforce or counteract projected increases in daily precipitation intensity as the climate warms. We analyze climate model projected changes in the number of dry days using 28 coupled global climate models from the Coupled Model Intercomparison Project, version 5 (CMIP5). We find that the Mediterranean Sea region, parts of Central and South America, and western Indonesia could experience up to 30 more dry days per year by the end of this century. We illustrate how changes in the number of dry days and the precipitation intensity on precipitating days combine to produce changes in annual precipitation, and show that over much of the subtropics the change in number of dry days dominates the annual changes in precipitation and accounts for a large part of the change in interannual precipitation variability."

[AbruptSLR]

Returning to bligh8's comments about evidence for recent westerly wind bursts (wwb), in his post (see link below) Jeff Masters provides the first attached image of wwb through March 6th (which helped reinforce the current Kelvin wave (EKW) into a strong position to start an El Nino condition by mid-April):

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2642

And while the next several days are not projected to have any wwb's, the second attached image from Cyclocane for the 48-hr Tropical Storm warnings, there is an increasing chance of a tropical cyclone in the south central tropical Pacific before mid-week, which could add some well positioned wwb's to add to the MJO and EKW surfacing around that timeframe.

Also, in the coming months, anyone interested can track this year's coming typhoons (and Super Typhoons), that could help kick future Kelvin waves (EKW's) into building the El Nino event being in April 2014 into a Super El Nino by late November to December 2014 (see the third attached image and the following link):

http://www.cyclocane.com/

[AbruptSLR]

Apparently, forecasts for the MJO track/strength are highly variable at this time of the year, and today's forecast (see attached three images with forecasts thru March 29 2014), which have the MJO bypassing the Western Pacific and moving straight into the Western Hemisphere.  While I do not have any meteorological background, this indicates to me that even if the MJO arrives in the Eastern Pacific by the end of this month, it may not have sufficient moisture/strength to have a major impact on the Walker Circulation Cell.  I guess that we will have to wait and see if the forecast changes yet again:

[AbruptSLR]

I thought that I would post the two following linked information about El Nino events:

The first link is focused on consequences (focused on farming) of the forecast El Nino this year:
http://www.farmforum.net/news/here-comes-el-nino/article_7f9ffc21-d210-5994-8316-e6e7db2a4b16.html


The second link is about the following 2010 article identifying a strong El Nino event from 1918-19 that was limited to the Central Equatorial Pacific, but which influenced the 1918-19 Spanish flu pandemic:
Giese, Benjamin S., Niall C. Slowey, Sulagna Ray, Gilbert P. Compo, Prashant D. Sardeshmukh, James A. Carton, Jeffrey S. Whitaker, 2010: The 1918/19 El Niño. Bull. Amer. Meteor. Soc., 91, 177–183.
doi: http://dx.doi.org/10.1175/2009BAMS2903.1

Abstract: "El Niño is widely recognized as a source of global climate variability. However, because of limited ocean observations during the early part of the twentieth century, little is known about El Niño events prior to the 1950s. An ocean model, driven with surface boundary conditions from a recently completed atmospheric reanalysis of the first half of the twentieth century, is used to provide the first comprehensive description of the structure and evolution of the 1918/19 El Niño. In contrast with previous descriptions, the modeled El Niño is one of the strongest of the twentieth century, comparable in intensity to the prominent events of 1982/83 and 1997/98."

http://www.esrl.noaa.gov/psd//data/20thC_Rean/

See also:
http://www.elnino.noaa.gov/pandemic_1918_1919.html

As a post script, I would like to note that while the MJO can strengthen, and or increase the probability of (or timing of), an El Nino event; the MJO does not cause or control an El Nino event.  Thus if the current Kelvin wave is strong enough, then an El Nino will happen this Spring, no matter what the MJO does. In this regard, I am also posting the attached image of the Albany University Vorticity & wind forecast for March 22, 2014; which shows weak trade winds between 5N & 5S all across the Western Pacific and across the dateline to about 160W.

[AbruptSLR]

The following statement (through March 9 2014) and attached SOI chart (through March 15 2014, and note that on March 15 the 30-day moving average SOI index is -7.5), from the Australian BoM, supports the idea that we are moving towards an El Nino event beginning around mid-April 2014:

"Southern Oscillation Index:
The Southern Oscillation Index (SOI) has continued to drop over the past two weeks, having dropped steadily over the past month from a peak of about +14. The latest approximate 30-day SOI value to 9 March is −6.3.

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."

[AbruptSLR]

The National Hurricane Center (see the following link), provides the following statement:

http://www.nhc.noaa.gov/text/refresh/MIATWDEP+shtml/100249_MIATWDEP.shtml

"TROPICAL WEATHER DISCUSSION                                   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT MAR 15 2014

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2100 UTC.                           

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...             

ITCZ EXTENDS FROM 07N85W TO 08N91W TO 03N100W TO 05N115W TO
03N125W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 02N
TO 09N BETWEEN 103W AND 120W."

To me presences of the intertropical convergence zone/monsoon trough in the Eastern Equatorial Pacific, might provide sufficient atmospheric convective activity in the next two to three weeks to possibly disrupt the normal Walker Circulation Cell pattern.

[AbruptSLR]

The following linked reference about the changing relationship between the wwv and ENSO; however, to me it seems to be overly influenced by the last 15 La Nina dominated years.  We will soon see whether the wwv leads the current possibly El Nino event by 2 to 3 months (as originally cited by deep octopus), or not:

Lucia Bunge and Allan J. Clarke, (2014), "On the warm water volume and its changing relationship with ENSO", Journal of Physical Oceanography 2014 ; e-View, doi: http://dx.doi.org/10.1175/JPO-D-13-062.1

http://journals.ametsoc.org/doi/abs/10.1175/JPO-D-13-062.1


Abstract: "Interannual equatorial Pacific 20°C isotherm depth variability since 1980 is dominated by two empirical orthogonal function (EOF) modes: The ‘tilt’ mode, having opposite signs in the eastern and western equatorial Pacific and in phase with zonal wind forcing and El Niño/Southern Oscillation (ENSO) indices; and a second EOF mode of one sign across the Pacific. Because the tilt mode is of opposite sign in the eastern and western equatorial Pacific while the second EOF mode is of one sign, the second mode has been associated with the warm water volume (WWV), defined as the volume of water above the 20°C isotherm from 5°S–5°N, 120°E–80W°. Past work suggested that the WWV led the tilt mode by about 2–3 seasons, making it an ENSO predictor. But after 1998 the lead has decreased and WWV-based predictions of ENSO have failed. We constructed a sea level-based WWV proxy back to 1955 and before 1973 it also exhibited a smaller lead. Analysis of data since 1980 showed that the decreased WWV lead is related to a marked increase in the tilt mode contribution to the WWV and a marked decrease in second mode EOF amplitude and its contribution. Both pre-1973 and post-1998 periods of reduced lead were characterized by “mean” La Niña-like conditions including a westward displacement of the anomalous wind forcing. According to recent theory, and consistent with observations, such westward displacement increases the tilt mode contribution to the WWV and decreases the second mode amplitude and its WWV contribution."

[AbruptSLR]

Bruce asked for additional background on why the PDO occurs, and I find the following Wikipedia linked information to be clear:

http://en.wikipedia.org/wiki/Pacific_decadal_oscillation

This link states:

"The Pacific Decadal Oscillation (PDO) is the leading EOF of monthly sea surface temperature anomalies (SSTA) over the North Pacific (poleward of 20° N) after the global mean SSTA has been removed, the PDO index is the standardized principal component time series.

The PDO is detected as warm or cool surface waters in the Pacific Ocean, north of 20° N. During a "warm", or "positive", phase, the west Pacific becomes cool and part of the eastern ocean warms; during a "cool" or "negative" phase, the opposite pattern occurs. It shifts phases on at least inter-decadal time scale, usually about 20 to 30 years.

The Pacific (inter-)decadal oscillation was named by Steven R. Hare, who noticed it while studying salmon production pattern results in 1997.

The prevailing hypothesis is that the PDO is caused by a "reddening" of the El Niño–Southern Oscillation (ENSO) combined with stochastic atmospheric forcing.

A PDO signal has been reconstructed to 1661 through tree-ring chronologies in the Baja California area.

The interdecadal Pacific oscillation (IPO or ID) displays similar sea-surface temperature (SST) and sea-level pressure (SLP) patterns, with a cycle of 15–30 years, but affects both the north and south Pacific. In the tropical Pacific, maximum SST anomalies are found away from the equator. This is quite different from the quasi-decadal oscillation (QDO) with a period of 8-to-12 years and maximum SST anomalies straddling the equator, thus resembling the ENSO."

It also states:

"Several studies have indicated that the PDO index can be reconstructed as the superimposition of tropical forcing and extra-tropical processes. Thus, unlike ENSO, the PDO is not a single physical mode of ocean variability, but rather the sum of several processes with different dynamic origins.

At inter-annual time scales the PDO index is reconstructed as the sum of random and ENSO induced variability in the Aleutian low, on decadal timescales ENSO teleconnections, stochastic atmospheric forcing and changes in the North Pacific oceanic gyre circulation contribute approximately equally, additionally sea surface temperature anomalies have some winter to winter persistence due to the reemergence mechanism."

The attached three figures also come from the Wiki article, and the first image shows how a positive ENSO pattern uses an "atmospheric bridge" to telecommunicate energy from the Equatorial Pacific to the Aleutian Low.

The second and third attached figures show how a positive PDO effects regional temperatures and precipitation, respectively.  These figures indicate that a positive PDO index value has a similar effect on regional temperature, and precipitation, patterns as does a positive ENSO index.

[AbruptSLR]

The Australian BoM provides (see link below) the attached image for March 16, 2014 indicating a growing probability of an El Nino event sooner, rather than later:

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

The attached image is of the 30-day rolling average of the SOI, which today is -7.9 while yesterday it was -7.5 and a sustained SOI index more negative than -8.0 indicates an El Nino event.


Also, according to the following article linear increases in the ENSO result in non-linear increases in precipitation in the Indo-Pacific area:

Christine T. Y. Chung, Scott B. Power,  Julie M. Arblaster,  Harun A. Rashid,  Gregory L. Roff, (2013), "Nonlinear precipitation response to El Niño and global warming in the Indo-Pacific", Climate Dynamics, doi: 10.1007/s00382-013-1892-8


http://link.springer.com/article/10.1007/s00382-013-1892-8


Abstract: "Precipitation changes over the Indo-Pacific during El Niño events are studied using an Atmospheric General Circulation Model forced with sea-surface temperature (SST) anomalies and changes in atmospheric CO2 concentrations. Linear increases in the amplitude of the El Niño SST anomaly pattern trigger nonlinear changes in precipitation amounts, resulting in shifts in the location and orientation of the Intertropical Convergence Zone (ITCZ) and the South Pacific Convergence Zone (SPCZ). In particular, the maximum precipitation anomaly along the ITCZ and SPCZ shifts eastwards, the ITCZ shifts south towards the equator, and the SPCZ becomes more zonal. Precipitation in the equatorial Pacific also increases nonlinearly. The effect of increasing CO2 levels and warming SSTs is also investigated. Global warming generally enhances the tropical Pacific precipitation response to El Niño. The precipitation response to El Niño is found to be dominated by changes in the atmospheric mean circulation dynamics, whereas the response to global warming is a balance between dynamic and thermodynamic changes. While the dependence of projected climate change impacts on seasonal variability is well-established, this study reveals that the impact of global warming on Pacific precipitation also depends strongly on the magnitude of the El Niño event. The magnitude and structure of the precipitation changes are also sensitive to the spatial structure of the global warming SST pattern."

[AbruptSLR]

The Australian BoM states:
"Cloudiness along the equator, near the Date Line, is an important indicator of ENSO conditions, as it typically increases (negative Outgoing Long-wave Radiation (OLR) anomalies) near and to the east of the Date Line during an El Niño event and decreases (positive OLR anomalies) during a La Niña event."

Therefore, unless I am mistaken, the attached image from the BoM for the OLR around the equatorial Date Line, show a negative OLR anomaly, which should indicate increasing cloudiness which could result in a disruption to the normal Walker Circulation into an El Nino pattern:

[SATire]

Hi AbruptSLR,

somehow the current at the equator in the pacific has made an U-turn in the last month - now it flows towards South America. I am not sure if that is really important in respect to El Nino - but it is surely nice to look at the curents with that beautiful earth wind map:
15th February: http://earth.nullschool.net/#2014/02/15/0000Z/ocean/surface/currents/orthographic=-148.67,-4.23,783
15th March: http://earth.nullschool.net/#2014/03/15/0000Z/ocean/surface/currents/orthographic=-148.67,-4.23,783

[Bruce Steele]

ASLR, re. PDO.  I tried to get through the Wiki piece but it didn't help me much. Posting here saying I don't get it doesn't help anyone I suppose but let me continue.
From Wiki. "the prevailing hypothesis is that the PDO is caused by a " reddening" of the ENSO combined with a stochastic atmospheric forcing."
 I looked up " reddening " and tried to get through Brownian noise to no avail and" stochastic forcing"reminded me of reading Tamino.   After that I went over to the JISAO Washington site and thankfully they said we don't understand the processes driving the PDO. Me neither.
 I have heard that PDO had something to do with the bifurcation of the Kuroshio current as it hits the north American continent. Sometimes the strength diverts mostly north ( warm water PDO ) and sometimes the strength is more evenly divided north and south ( cold water PDO ). Rummaging around hasn't resulted in the Kuroshio connections but that big Pacific high we had  makes me wonder about it's placement this winter and also how a weakened Aleutian low plays into all this? If I had a professor to bounce this off of those are the questions I would be asking .
 Maybe I should stick to talking about fish ?
     

[AbruptSLR]

Bruce,
Not that I am an expert of any kind, but I will say that: The ENSO and PDO phenomena are prime examples of systems that are best described by "Chaos Theory".  Unfortunately, both of these systems are too complex to be currently addressed using pure chaos theory, and therefore, we can revert to linear Global/Regional Circulation Models (and ensemble mean projections, as example for the MJO see the first attached image of an ensemble mean projection issued on March 16 2014 saying that the MJO will not be in the Eastern Equatorial Pacific before the end of March) , and/or we can use statistics and empirical functions (see the second attached image of an empirical projection issued on March 16 2014 saying that the MJO will be in the Eastern Equatorial Pacific before the end of March).

Regarding the two terms that you mentioned from the Wiki article: (a) A purely stochastic system is one whose state is non-deterministic (i.e., "random"); and the atmosphere is a good example; and (b) Reddened refers to red and white noise on the Nino-indices, which is to say red plus white noise on the SST anomalies (ie during a neutral ENSO condition you have white noise for equatorial Pacific SST anomaly (SSTA); otherwise, when the Nino-indices show either an El Nino or a La Nina condition, then you have a red noise signal with regard to the equatorial Pacific SSTA.

If you feel up to it you can download and read the linked free access papers on such matters, but all researchers will admit that the theories about IPO, PDO, MJO, ENSO and other "Chaotic" systems (all with strange attractors) are works in progress even in a stationary world, let alone in our current non-stationary world:

http://www.knmi.nl/publications/fulltexts/artikel3_syphilip_color.pdf

http://journals.ametsoc.org/doi/pdf/10.1175/2007JCLI1665.1

[AbruptSLR]

While my previous posts have discussed both the potential impact, and uncertainties (see my immediate prior post), of the MJO reaching the Date Line area by the end of March 2014 in flipping the Walker Cell into an El Nino pattern by creating storm activity near the Equatorial Pacific Date Line area.

I also posted earlier today that the Australian BoM provides OLR anomaly data indicating that cloudiness is currently accumulating near the Equatorial Pacific Date Line area, and the following Cyclocane Tropical Storm 48-hour forecast (issued on March 16 2014) and the following storm warming (from Cyclocane) indicates that there we be considerable convective activity near the Equatorial Pacific Date Line area, that would make it unnecessary for the MJO to make it to the Date Line area in order to change the Walker Cell to an El Nino pattern:

Cyclocane forecast for the South Central Pacific:

"THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.8S
170.1E IS NOW LOCATED NEAR 14.6S 170.7E, APPROXIMATELY 215 NM EAST
OF VANUATU. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A BROAD
LOW-LEVEL CIRCULATION CENTER (LLCC) WITH MULTIPLE CIRCULATIONS
ROTATING ABOUT A CENTROID (THE CURRENT POSITION) WITH ISOLATED DEEP
CONVECTION FLARING OVER THE LLCC. A 160336Z SSMI IMAGE SHOWS TWO
DISTINCT SMALL LLCCS WITH OVERALL WEAK CONVECTIVE BANDING. A 152132Z
ASCAT IMAGE ALSO SUPPORTS MULTIPLE CIRCULATIONS AND SHOWS 15 TO 20
KNOT WINDS AROUND THE PERIPHERY OF THE LLCC. THE SYSTEM IS LOCATED
EQUATORWARD OF THE UPPER-LEVEL RIDGE AXIS AND IS UNDER MODERATE
EASTERLY VERTICAL WIND SHEAR. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1006 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS LOW."

[AbruptSLR]

SATire,

Thanks for the earth map surface current map links for the Pacific Ocean for February and March 15, here is a link for March 16th showing what looks like an increasing tread to an El Nino condition:

http://earth.nullschool.net/#2014/03/16/0000Z/ocean/surface/currents/orthographic=-148.67,-4.23,783

While I believe that deep octopus is more qualified (see his reply #173 on March 9) than myself to talk about the transition of surface and subsurface Pacific Equatorial Currents from a "Normal" to an "El Nino" condition, I will provide the following:

The first attached image shows a cartoon of the stereotypical changes in atmospheric and subsurface conditions from a "Normal" to an "El Nino" condition.

The second attached image shows a more elaborate cartoon for an "El Nino" condition showing the interaction of the surface, subsurface, wind and storm activities.

The third attached image shows another cartoon of how the Pacific Equatorial Counter current strengthens in the Eastern Equatorial Pacific during an El Nino condition (note that I am not sure that this is a very accurate cartoon as the atmospheric pattern seems to me to be more like a "Normal" Walker Cell pattern, but I am posting it to illustrate how in an El Nino condition the surface ocean Equatorial Countercurrent strengthens).

The fourth attached image shows "Normal" ocean surface currents, indicating the complex interaction of all of these currents on the state of the Pacific Ocean and all of these Pacific currents effect and are effected by a change to an El Nino state.

Also, I agree that just watching the earth map of Equatorial Pacific ocean surface currents is fascinating by itself, and it will be interesting to watch it change in the coming month(s).

Best,
ASLR

[AbruptSLR]

Further to my post today to Bruce Steele (reply #239) about the differences between truly "Chaotic Systems" (eg: ENSO, PDO, IPO, MJO, etc) and approximate forecasts of such chaotic systems base on: (a) process-based GCM ensemble mean projections; and/or (b) statistical-based empirical indices/parameters/graphs etc. (eg Nino 3.4, SOI, MEI, etc), I would like to make the following comments:

(A) El Nino events are statistically more intense (ie can have higher index values) than La Nina events (see the first attached image of the Multivariate ENSO Index, MEI from 1950 to March 6 2014) , thus using the 2010-11 La Nina MEI value of about -2, I would guess that the 2014-15 El Nino could well have a MEI value of over +3.
(B) Models indicate that a Super El Nino can trigger both the PDO and IPO oscillations from a negative phase into a positive phase, as was apparently the case for the 1983-84 Super El Nino that was followed by about 15-years of positive IPO.  Therefore, if we do has a Super El Nino in the 2014-15 season it will likely kick the IPO into a sustained positive phase.
(C) The following linked reference by Power & Kociuba (2010) states: "The 2010 global warming signal is already a major contributor to interdecadal variability in the SOI, equal to 45% of the standard deviation of 30-year running averages of the SOI. This figure is projected to increase to nearly 340% by the end of the 21st century."  This statistical evidence supports the other evidence provided by the selected references at the end of this post that El Nino's will get stronger with increasing global warming.

http://www.cawcr.gov.au/staff/sbp/journal_articles/GW_the_SOI_Power_Kocuiba_CD_2010.pdf

(D) As I have stated before, I believe that there is both paleo and modern observations that climate sensitivity is greater during warming periods than during cooling periods, and that as most process-based GCM projections do not include a ratcheting influence of strong El Nino events to strengthen such positive feedback factors as polar amplification, and carbon cycle sensitivity (among others); I am concerned that at least for the next 15-years we will see greater rates of global warming acceleration due to ENSO/PDO/IPO feedback mechanisms, than are currently recognized.

Selected References on ENSO and Global Warming:
[1]   Cai, W., Borlace, S., Lengaigne, M., Rensch, P.V., Collins, M., Vecchi, G., Timmermann, A., Santoso, A., McPhaden, M., Lixin Wu, Matthew H. England, Guojian Wang, Eric Guilyardi & Fei-Fei Jin, (2014), "Increasing frequency of extreme El Niño events due to greenhouse warming", Nature Climate Change, doi:10.1038/nclimate2100.
[2]   Cowtan, K. & Way, R.G., (2013), "Coverage bias in the HadCRUT4 temperature series and its impact on recent temperature trends", Quarterly Journal of the Royal Meteorological Society, DOI: 10.1002/qj.2297.
[3]   England, M.H., McGregor, S., Spence, P., Meehl, G.A., Timmermann, A., Cai, W., Gupta, A.S., Michael J. McPhaden, M.J., Purich A. & Santoso, A., (2014), "Recent intensification of wind-driven circulation in the Pacific and the ongoing warming hiatus", Nature Climate Change, doi:10.1038/nclimate2106.
[4]   Fasullo, J.T. and Trenberth, K.E., (2012), "A Less Cloudy Future: The Role of Subtropical Subsidence in Climate Sensitivity", Science, vol. 338, pp. 792-794, 2012. http://dx.doi.org/10.1126/science.1227465.

[Apocalypse4Real]

AbruptSLR,

You beat me to the punch on this, but here is more. If you read the discussion on the MEI page, Klaus Wolter gives the detailed breakdown of his more bullish forecast of an early El Nino. I think he anticipates it appearing early, he commented that he expected to provide another update sooner than the first week of April. One more item, he says the SOI has been the noisiest of the El Nino indicators, so not so sure he is putting alot of weight on where it currently reads.

For his detailed analysis, see:
http://www.esrl.noaa.gov/psd/enso/mei/

Also, for what it is worth, I compiled a comparison of the 1950 to 2014 MEI, normal 3 month ENSO and the monthly ENSO indices. It was a bit of work but worth the time.

Here are the recent readings in comparison:



   

[AbruptSLR]

A4R,

Thanks for the information/analysis.  I admit that in the middle of the Spring barrier there is plenty of unknowns/uncertainties that could cause the El Nino train to come off of its tracks.  Nevertheless, I see so many indications that we are already in the initial stages of the transition into an El Nino event, that it seems to me that by the beginning of April we will be locked into conditions that will support at least a weak El Nino thru at least this Summer.  Therefore, the main question currently in my mind is whether we will get more strong Kelvin waves (EKWs) to boost conditions up into the "Super" category above an MEI of +2, while my gut tells me that we might even exceed an MEI of +3 in the Dec 2014 to February 2015 timeframe, given: (a) the amount of heat in the Pacific Ocean; (b) the fact that the "hiatus" has masked the true extent of the current global warming; (c) that the ensemble forecasts show clear signs of strong positive PDO values in April and May; (d) that if I am right and an El Nino begins by early April (by all ENSO indices not just SOI) then there will be the longest time in modern observations to build-up a Super El Nino by the coming austral summer (note that the Nino3.4 index for the 1997-98 El Nino did not exceed +0.5 until the week of April 23rd).  Fortunately, as a blogger, I do not need to be as conservative as professional ENSO forecasters need to be (correctly so), so I have a window between now and Klaus Wolter's next up-date, to post about the unfolding of this potentially critical event.

Best,
ASLR

[AbruptSLR]

The linked reference may be of somewhat academic interest with regard to ENSO and the IPO, but I found the statement that the South Pacific convergence zone (SPCZ) is the world's largest rainfall band during the austral summer, interesting:

M. J. Salinger, Simon McGree, Florent Beucher, Scott B. Power, François Delage (2014), "A new index for variations in the position of the South Pacific convergence zone 1910/11–2011/2012", Climate Dynamics , DOI: 10.1007/s00382-013-2035-y

http://link.springer.com/article/10.1007%2Fs00382-013-2035-y

Abstract: "Quality controlled and recently homogenised mean sea level pressure records for the South Pacific are used to specify the location and variability of the South Pacific convergence zone (SPCZ) during the austral warm season (November–April). The SPCZ is the world’s largest rainfall band during the austral summer, when it dominates the climate of the South Pacific. A new index called the South Pacific convergence zone index (SPCZI) is derived, and is shown to be coherent with changes in low level wind convergence associated with the SPCZ. This index replaces the earlier SPCZ position index because it uses higher quality mean sea level pressure data than the superseded index and extends the time series further forward in time. The SPCZI allows interannual to decadal variability in the climate of the South Pacific to be tracked for more than a century from 1910/1911 to 2011/2012. During El Niño episodes the SPCZ is displaced by about 1°–3° east, and La Niña events 1°–3° west of the mean position on average. The index indicates a striking movement eastward for the period 1977/78–1998/99, compared with 1944/45–1976/77 in association with the Interdecadal Pacific oscillation (IPO). The eastward movement of the SPCZ in the late twentieth century is related to significant precipitation trends in the South Pacific region. Since 1998/99 the SPCZ has regressed westward with the negative phase change of the IPO. The long-term trend in the SPCZI is very small relative to the interannual to decadal variability and is not statistically significant, suggesting that there has been little overall change in the mean position of the SPCZ over the past century."

[AbruptSLR]

While I am aware that the SOI is the noisiest of all ENSO indices, it can also give earlier warnings of strong El Nino events than other, more process-based conservative, indices.  Therefore, it is possible that the first attached image of the SOI 30-day rolling average value of -8.4 may be the first indication that the Pacific has now changed into an El Nino state, and possibly the beginning of a strong El Nino event.

The second image of NOAA's ensemble Nino3.4 forecast issued on March 16 2014 (based on March 6 to 15 conditions) indicates that some of the process-based models have Nino3.4 values over +2 by November 2014, and an ensemble mean forecast of about +1.5 by the mean of OND.  As NOAA's Nino3.4 is reasonably conservative, I expect the actual Nino3.4 value to be well about +2 before December 2014.  This ENSO season should be quite something to watch unfold.

[AbruptSLR]

For those interested in the monthly SOI values for the 1982-83 and the 1997-98 Super El Nino events, I provide the following abbreviated table of monthly SOI values from the Australian BoM website:

Year   Jan     Feb     Mar     Apr     May    Jun     Jul      Aug     Sep     Oct     Nov     Dec
1981   2.7     -3.2    -16.6  -5.5     7.6     11.5    9.4      5.9     7.5    -5.0     2.6      4.7
1982   9.4      0.6     2.4    -3.8    -8.2    -20.1   -19.3   -23.6  -21.4   -20.2  -31.1   -21.3
1983   -30.6  -33.3  -28.0   -17.0   6.0     -3.1    -7.6     0.1     9.9      4.2    -0.7      0.1

1996    8.4     1.1      6.2     7.8    1.3     13.9     6.8    4.6      6.9      4.2    -0.1      7.2
1997    4.1     13.3   -8.5   -16.2  -22.4   -24.1   -9.5   -19.8  -14.8   -17.8  -15.2    -9.1
1998   -23.5  -19.2  -28.5  -24.4    0.5      9.9     14.6    9.8    11.1    10.9    12.5   13.3

This abbreviated table implies that we could see SOI values of between -28 to more negative than -33 this coming austral summer.

[AbruptSLR]

For anyone wondering how strange attractors in chaos theory could be used to project ENSO, IPO, PDO, etc. behavior in a chaotic forced atmosphere-ocean circulation system, then I recommend that you read the linked 2010 article at skepticalscience.com:

http://www.skepticalscience.com/chaos-theory-global-warming-can-climate-be-predicted-intermediate.htm

[AbruptSLR]

The first attached image showing the location of the South Pacific Convergence Zone, SPCZ is from the following Wiki link (after Folland et al 2002), and the following quote is also from the Wiki link (see also the reference in reply #245):

http://en.wikipedia.org/wiki/South_Pacific_convergence_zone

"Research into SPCZ movements of the 20th century are linked to changes in the IPO and ENSO. Folland et al., 2002 defined an index to describe the Interdecadal Pacific Oscillation (IPO) with sea surface temperature and night marine air temperature to determine how the SPCZ varies with the IPO. When the IPO index has negative temperature anomalies, the SPCZ is displaced southwest and moves northeastward when the IPO index has positive temperature anomalies. The Southern Oscillation Index (SOI) is a metric for describing warm- and cold-phase conditions associated with the El Niño-Southern Oscillation (ENSO) and can also describe movements of the position of the SPCZ. Negative SOI index values are associated with warm-phase or El Nino-like conditions and a northeastward displacement of the SPCZ. Positive SOI index values, on the other hand, describe cold-phase or La Nina-like conditions and a southwestward displacement of the SPCZ."

This reference clearly indicate that El Nino conditions are associated with a Northeastward displacement of the SPCZ, while the second and third attached image (from the following linked sites, for the Western and Eastern Pacific, respectively) show the cloud cover for March 17 2014 that is associated with the SPCZ, and these images clearly indicate that the SPCZ has shifted to the Northeast indicating El Nino-like conditions:

http://www.goes.noaa.gov/FULLDISK/MTVS.JPG
http://www.goes.noaa.gov/FULLDISK/GWVS.JPG