In the preceding post, we looked at the evolution of the weekly sea surface temperature anomalies in two regions of the equatorial Pacific (NINO3.4 and NINO1+2), comparing the data so far in 2014 to those of the strong 1982/83 and 1997/98 El Niño events. (See 2014/15 El Niño – Part 3 – Early Evolution – Comparison with 1982/83 & 1997/98 El Niño Events.) We presented them because there are a lot of comparisons of this El Niño to those strong El Niños.
In this post, using the same two regions, we’ll compare the evolution of the sea surface temperature anomalies this year to the rest of the satellite-era El Niño events. And we’ll also compare this year to the average, because someone was bound to ask.
This post serves solely as a reference. What it illustrates very well is that there is a tremendous amount of diversity in the evolutions of sea surface temperatures during El Niño events. A tremendous amount of diversity.
Are you ready for some spaghetti?
BEFORE WE START
The processes that initiate each El Niño are basically the same: a downwelling (warm) Kelvin wave heads east along the equator in the Pacific. We illustrated this year’s downwelling Kelvin wave in the first post in this series. The waters at the surface and below the surface of the equatorial Pacific are normally warmer in the west than in the east. So the downwelling Kelvin wave, which is carrying (basically shifting) warm water from west to east below the surface, causes the subsurface temperatures to be warmer than normal along the central and eastern portions of the equator. That warmer-than-normal subsurface water is drawn to the surface in a process called upwelling, and when it reaches the surface, the sea surface temperature anomalies begin to increase along the central and eastern portions of the equatorial Pacific. That’s where we are. The warmer-than-normal subsurface water is being drawn to the surface.
Now consider that the Kelvin waves don’t start at exactly the same time each year…and the Kelvin waves don’t have the same amount of warm water available, so they don’t all create the same subsurface temperature anomalies…and the sea surface temperatures at the start of each El Niño are somewhat different…and the strengths of the trade winds can also be different…and a multitude of other background states are all in different states. That’s why we’re going to see a lot of spaghetti when we compare the evolution of this year’s sea surface temperature anomalies with all the other satellite-era El Niños.
COMPARISONS WITH OTHER SATELLITE-ERA EL NIÑOS (NOT 1982/83 & 1997/98 EL NIÑOS)
Figures 1 and 2 illustrate the evolutions of the weekly sea surface temperature anomalies from the first week in a given year through the 60th week, so the data stretch into the first few months of the second year of each El Niño. (El Niños normally peak in boreal winter, because they are tied to the seasonal cycle.) The NOAA Oceanic NINO Index (ONI) was used as a reference for “official” El Niño events. We’re using the weekly Reynolds OI.v2 data, which starts in late 1981. In addition to where we stand so far for the 2014/15 El Niño (highlighted in red), Figures 1 and 2 also include the evolutions of the sea surface temperature anomalies for the 1986/87 El Niño, 1991/92 El Niño, 1994/95 El Niño, 2002/03 El Niño, 2004/05 El Niño, 2006/07 El Niño and the 2009/10 El Niño. Figure 1 is for the NINO3.4 region, which is located on the east-central portion of the equatorial Pacific (5S-5N, 170W-120W). Figure 2 is for the NINO1+2 region, and it is located in the eastern equatorial Pacific (10S-0, 90W-80W), just south and west of the Galapagos Islands.
You’ll note also that I’ve highlighted the 2006/07 El Niño. Of the group shown, it is the only east Pacific El Niño. The others are El Niño Modoki (central Pacific El Niños). See the posts There Is Nothing New About The El Nino Modoki and Comparison of El Nino Modoki Index and NINO3.4 SST Anomalies, and also see the JAMSTEC ENSO Modoki webpage (El Niño Modoki are a new category. Historically, they are not a new type of event.)
There’s so much spaghetti in the following two graphs, there’s no reason for me to describe them, other than to say there’s lots of diversity during the evolutions of El Niño events.
Figure 1
# # # #
Figure 2
Obviously, each El Niño starts from a different background, in terms of sea surface temperature anomalies. (We’ve already discussed the ocean heat content and subsurface temperature anomalies, noting that both are lower now than they were at the start of the 1997/98 El Niño. See the post here.)
COMPARISONS WITH AVERAGES OF SATELLITE-ERA EL NIÑOS (INCLUDING THE 1982/83 & 1997/98 EL NIÑOS)
Figures 3 and 4 follow the same formats. But with them, we’re comparing the evolutions of the 2014/15 El Niño (so far) to the averages of all of the satellite-era El Niño events, including the 1982/83 and 1997/98 El Niños. Now in 2014, NINO3.4 sea surface temperature anomalies are warmer than average, and NINO1+2 anomalies are cooler than average.
Figure 3
# # # #
Figure 4
Do the below-average readings in the NINO1+2 region mean that the 2014/15 El Niño will be a central Pacific El Niño and not the stronger east Pacific variety? Not necessarily. As you’ll recall from Part 3 of the series, the 2014 NINO1+2 values are similar to those at the start of the 1982/83 El Niño. See the graph here. And the 1982/83 El Niño was a strong El Niño—no doubt about that.
SOURCES
The weekly sea surface temperature anomaly data presented in this post is available through the NOAA NOMADS website:
http://nomad1.ncep.noaa.gov/cgi-bin/pdisp_sst.sh
or:
http://nomad3.ncep.noaa.gov/cgi-bin/pdisp_sst.sh?lite=
EARLIER POSTS IN THIS SERIES
- The 2014/15 El Niño – Part 1 – The Initial Processes of the El Niño.
- The 2014/15 El Niño – Part 2 – The Alarmist Misinformation (BS) Begins
- The 2014/15 El Niño – Part 3 – Early Evolution – Comparison with 1982/83 & 1997/98 El Niño Events
FURTHER READING
My ebook Who Turned on the Heat? goes into much more detail to explain El Niño and La Niña processes and the long-term aftereffects of strong El Niño events. I’ve lowered the price of Who Turned on the Heat? from U.S.$8.00 to U.S.$5.00. A free preview in pdf format is here. The preview includes the Table of Contents, the Introduction, the first half of section 1 (which was provided complete in the post here), a discussion of the cover, and the Closing. Take a run through the Table of Contents. It is a very-detailed and well-illustrated book—using data from the real world, not models of a virtual world. Who Turned on the Heat? is only available in pdf format…and will only be available in that format. Click here to purchase a copy. Thanks.
NEXT POST
The next post in the series will be about the Pacific Decadal Oscillation (PDO) and its relationship to ENSO…unless, of course, the weekly NINO3.4 sea surface temperature anomalies reach the 0.5 deg C threshold of an El Niño. I started writing the PDO post about a month ago. It’s an appropriate time to raise the topic again since the PDO is often referred to in blog posts about the upcoming El Niño.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
I am now suffering from spaghetti overdose and need to retire and consider the matter. yet again.
As for any answer, like the weather, we will wait and see.
Interesting. It seems the definition of “El Nino” evolves.
What it shows is that there is no pattern. At least not in recent El Ninos. But that is what the slow process of data gathering is all about.
Based on some earlier studies I believe it will turn to La- Nina from June July.
Bob, after studying figure 3 I am convinced this years ENSO is related to the Loch Ness Monster. I am not sure what this indicates but I am enjoying your series as always.
El Nino is not a cause, it is a hindsight description. This coming winter should see plenty of rain for most Australian states except NT, parts of WA and TAS. For that and other reasons, particularly the still high solar count, El Nino is not set to start until July 2015, and continue at least until the end of 2015. After that, the next EL Nino is due around 2020. Also a major Australian drought is due 2019-21.
El Ninos are a function of lunar declination. The 1987 EL Nino occurred concurrent with maximum declination, 1997 EL Nino with minimum declination, 2006 EL Nino with maximum declination, and a 2015 EL Nino with the next minimum declination. For EL Nino to occur in 2014 would betray the pattern. Claiming it is imminent is just alarmist propaganda that sells newspapers and qualifies yet again as a funding grab.
Thanks for advancing the knowledge base, Bob. Real world data is much messier than simple theories. Your grip on ENSO realities grows ever stronger and is of great assistance to the science-reading community. In particular the physical explanations following the heat through the oceans have generated some of the most useful graphics available. Thanks.
kenmoonman, can you post the reason for El Ninos are a function of lunar declination
A correction Bob:
“So the downwelling Kelvin wave, which is carrying (basically shifting) warm water from west to east below the surface, causes the subsurface temperatures to be warmer than normal along the central and eastern portions of the equator”
The Kelvin wave is not carrying warm water from west to east. Kelvin waves transmit energy, not mass, within the ocean. The downwelling Kelvin wave is pushing the thermocline deeper, creating warm subsurface temperature anomalies. When the downwelling Kelvin wave and subsurface temperature anomalies reach the eastern Pacific, the subsurface temperature anomalies are carried by equatorial upwelling into the mixed layer, generating warm SST anomalies. Additionally, zonal current anomalies created by the downwelling Kelvin wave displace the western Pacific warm pool to the east.
You may find the review by Wang et al. [2012] useful. http://www.cgd.ucar.edu/cas/cdeser/Docs/submitted.wang.enso_review.pdf
kenmoonman says:
April 18, 2014 at 4:44 am
“El Ninos are a function of lunar declination. The 1987 EL Nino occurred concurrent with maximum declination, 1997 EL Nino with minimum declination, 2006 EL Nino with maximum declination, and a 2015 EL Nino with the next minimum declination. For EL Nino to occur in 2014 would betray the pattern. Claiming it is imminent is just alarmist propaganda that sells newspapers and qualifies yet again as a funding grab.”
———————
AH SO, ….. I see what you mean, to wit:
“The Moon’s maximum and minimum declination also varies because the plane of the Moon’s orbit around the Earth is inclined by about 5.14° to the ecliptic (the plane of the Earth’s orbit around the Sun), and the direction of lunar orbit inclination gradually changes over an 18.6-year cycle, ………..
Then, 9.3 years later, during the major lunar standstill, the Moon will change its declination during the nodal period from +28.5° to −28.5°, which is a total movement of 57°, which is enough to take its culmination from high in the sky to low on the horizon in just two weeks (half an orbit).”
The following table shows some occasions of a lunar standstill. The times given are for when the moon’s node passed the equinox—the moon’s greatest declination occurs within a few months of these times, depending on its detailed orbit.[3][4] However, the phenomenon is observable for a year or so on either side of these dates.[1]
Times of lunar standstill
major standstill minor standstill
May 1988 February 1997
June 2006 October 2015
April 2025 March 2034[5]
September 2043[5] March 2053[5]
Source: http://en.wikipedia.org/wiki/Lunar_standstill
=====================
It’s always a good day ….. when one learns something new.
The best short-term predictor of the ENSO is the upper 300M ocean temperature anomaly from 180W to 100W. It provides 1 to 2 month lead-time and also indicates the potential strength of the ENSO.
Back to 1979 here.
http://s29.postimg.org/e755lh7ef/ENSO_vs_EUOTA_Mar14.png
The current weekly values appear to have peaked at 1.7C for now which signals a short-lived summer El Nino in the 1.7C range.
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/heat-last-year.gif
The 1972-73 El Nino is probably a good model since it occurred in the middle of a cool PDO period.
It was fairly large getting to +2.12C making it the 8th biggest El Nino (+2.5C being super category).
Global Temperatures responded to the 1972-73 El Nino as expected (lagging behind by 3 months) and we saw a temporary upswing and then a downswing as the El Nino ended and was then followed by an equally strong La Nina which got to -2.25C exactly one year later.
Zoom-in of 1970 to 1976 with Nino 3.4 (not lagged) and scaled to its usual impact on global temperatures of 0.08.
http://s4.postimg.org/kcb9jx6a5/1972_El_Nino.png
kenmoonman says: “El Ninos are a function of lunar declination. The 1987 EL Nino occurred concurrent with maximum declination, 1997 EL Nino with minimum declination, 2006 EL Nino with maximum declination, and a 2015 EL Nino with the next minimum declination. For EL Nino to occur in 2014 would betray the pattern.”
Your hypothesis overlooks all of the other El Nino events.
Joseph Murphy says: “Bob, after studying figure 3 I am convinced this years ENSO is related to the Loch Ness Monster.”
I thought that red wiggle looked familiar. Thanks, you made me laugh.
Bill Illis says: “The current weekly values appear to have peaked at 1.7C for now which signals a short-lived summer El Nino in the 1.7C range.”
The other possibility is that that is just a temporary peak. The monthly data in your longer-term illustration show some temporary setbacks in the evolutions of some El Ninos…but not others. Time will tell…as we keep saying.
In some respects, a short-lived El Nino would be nice. In other respects, I’d welcome a super El Nino…just to study it.
Many thanks Bob, excellent study as per usual.
I have been following but only comparing with 97/98 (major) and 09/10 (latest). It would appear (will stand correction) that the present, if it plays out, is starting from a higher global SST base. Approx +0.3c (Reynolds Wk 15) versus approx 0.15C for 97/98 and 09/10. Any thoughts on how this event may eventually effect global SST?
The E Nino wishers are getting a little dose of TSI from the sun as activity increases again in last week or so after calming down for a last month. I do believe Spikes in TSI increase the chance of El Nino’s if weather patterns are right. If timing is right with all weather patterns extreme events are Always the out come. Timing Timing Timing.
http://www.solen.info/solar/
“In some respects, a short-lived El Nino would be nice. In other respects, I’d welcome a super El Nino…just to study it”
Looking at real events and data doesn’t work as they do not match the hypothesis. You do not need one to take place as there are a thousand computer simulations to show the nex super el-nino will fry us all. If that doesn’t get us farting cows will.
Bob Tisdale, it is difficult to tabulate all EN events, especially when EN’s only got to be named after 1982. The SOI is the true thing to watch, and therefore the switch to EN rather than the EN itself. In the 13 years between 1965-97 there have been 7 significant change-to-ENs of SOIs greater than values of -10
1965 (-15)
1972 (-11)
1976(-13)
1982(-22)
1987(-11)
1991(becomes -14)
1997(-16)
http://www.longpaddock.qld.gov.au/products/australiasvariableclimate/ensoyearclassification.html
That is an average of one every 4.5 years, roughly a quarter of the lunar cycle. These years are ALL either at or within a year of averagely more distant lunar perigees, those years being 1965, 1973, 1977, 1983, 1987, 1991, 1996. It is as if the switch to stabilise west/east sea-level differentials via the SOI current reversal happens when the moon’s ‘hold’ on currents is relatively weaker..
The next relatively distant period of average perigee is late 2015 through 2016. I would suggest it is a convincing case for the next EN to begin during the second half of 2015 and not before.
kenmoonman says: “…It is as if the switch to stabilise west/east sea-level differentials via the SOI current reversal happens when the moon’s ‘hold’ on currents is relatively weaker.”
You may be onto something. I’d like to see some diagrams. I’ve never found any overwhelmingly convincing argument re why the bulge “sloshes” east when it does. Lunar forces may be part of this, though my feeling is that, given enough bulge, it won’t take much to trigger it, so it could be other things, possibly minor equatorial cyclonic storms, as Bob has mentioned previously, or other asymmetric forces acting on the trade winds. And once the bulge starts to move, the momentum is huge; nothing will stop it.
We don’t need no stinkin’ science. It’s all Bush’s fault. Debate over.
love,
Barack
What about all the other years that started off like the El Niño years and never developed.
Some of them looked just like this.
Each time it goes a bit positive El Niño is called. Eventually one time it will be right .
There is no diagnosis here or else we would all know when every El Niño will occur..
More ice in the Antarctic for last 2 years.
Should be an avalanche of cold water heading equator wards for next 5 years so odds favour Kla Nina but so many factors to consider.
I recommend Trader Joe’s marinara sauce with spaghetti. The big can.
Good work, Bob. Thanks.
Thanks, Bob. A good article helping understand more about ENSO.
Thanks to your good work there is now a lot more understanding of this critical climate feature of Earth’s ocean circulations.
I have just published an article on the AMO, but it was not complete without quoting your work.