Guest post by Bob Tisdale
This is the first of a series of posts that address many of the myths and misunderstandings about the tropical Pacific processes that herald themselves during El Niño and La Niña events. Most of the content will be chapters from my recently published ebook Who Turned on the Heat?
For almost 4 years, my presentations about the long-term effects of El Niño and La Niña events indicate the global oceans over the past 30+ years have warmed naturally. This puzzles many proponents of anthropogenic global warming. They see the often-used name for the coupled ocean-atmosphere process—El Niño-Southern Oscillation (ENSO)—and assume the processes are oscillatory or cyclical. They will then post a comment to the effect of:
What part of oscillation don’t you understand?
Or
Haven’t you ever heard of the ENSO cycle? El Niño and La Niña are parts of a cycle. How can a cycle cause long-term global warming?
Comments like that are the first clue their authors are arguing from ignorance; that is, they have no understanding of the subjects being discussed—none whatsoever.
First off, it indicates those persons have never examined an ENSO index, such as the sea surface temperature anomalies of the NINO3.4 region—an area along the eastern equatorial Pacific bordered by the coordinates of 5S-5N, 170W-120W. ENSO indices are used to indicate how often El Niño and La Niña events happen, how strong they were, and how long they lasted. If El Niño and La Niña events were cyclical, they’d transition between El Niño and La Niña then back to El Niño and on to La Niña again, and so on. But they don’t cycle between El Niños and La Niñas. There can be back-to-back and back-to-back-back El Niño conditions without La Niña conditions appearing between them. See Figure 1. And there can be the double-dip La Niñas, like we’ve experienced recently.
Figure 1
Part of the confusion stems from the term El Niño-Southern Oscillation, which is really the combination of two names. Some of the confusion stems from the attempts of climate modelers who often treat the processes of ENSO as cycles in their failed attempts to simulate ENSO.
CHAPTER 2.1 DO THE WORDS “OSCILLATION” AND “CYCLE” IN THE NAMES “EL NIÑO-SOUTHERN OSCILLATION AND “ENSO CYCLE” CAUSE MISUNDERSTANDINGS?
The words oscillation and cycle are used to describe the processes of El Niño and La Niña events as a single phenomenon. The commonly used term ENSO stands for El Niño-Southern Oscillation. The seemingly redundant term ENSO Cycle (El Niño-Southern Oscillation Cycle) is also used often. Many persons assume because cycle and oscillation are used to describe El Niño and La Niña that the two states oppose and offset one another, that a La Niña will counteract an El Niño. Bad assumptions. They definitely do not work that way.
The most obvious difference between the two states, which we discuss in Sections 1 and 3, is, El Niño events randomly release vast amounts of warm water from below the surface of the west Pacific Warm Pool and spread it across the central and eastern equatorial Pacific, but the reverse does not occur during La Niña events.
Are El Niño and La Niña events cyclical or oscillatory? Some parts are, and some parts aren’t. We’ll discuss this further in Chapter 4.17 ENSO – A Cycle or Series of Events?
AN OVERVIEW OF THE TERMS EL NIÑO-SOUTHERN OSCILLATION AND ENSO CYCLE
El Niño-Southern Oscillation is the combination of two names. The term is said to have been coined by Rasmussen and Carpenter in their (1982) paper Variations in Tropical Sea Surface Temperature and Surface Wind Fields Associated with the Southern Oscillation/El Niño. Let’s see what Rasmussen and Carpenter have to say about the individual components. Their Introduction begins with the term El Niño:
The interannual variability of sea surface temperature (SST) along the Peru-Ecuador coast is dominated by the El Niño phenomenon. The name El Niño was originally applied to a weak warm coastal current which annually runs southward along the coast of Ecuador around the Christmas season (Wyrtki 1975). In scientific usage, the term has now become more narrowly associated with the extreme warmings which occur every few years (Wyrtki 1979a), and which result in catastrophic effects on the ecological system of the region. In more recent years, Ramage (1975), Weare et al. (1976), and others have used the term to encompass the larger-scale features of the warming event; i.e., the upwelling area along both the equator and the South American coast.
A few paragraphs later, Rasmussen and Carpenter describe the Southern Oscillation after discussing some initial findings from as far back as 1897:
It remained, however, for Sir Gilbert Walker, in a classical series of papers (Walker, 1923, 1924, 1928; Walker and Bliss, 1930, 1932, 1937) to name the SO [Southern Oscillation] and describe the salient features of the surface pressure, temperature and precipitation fluctuations.
The full title of the first Walker paper is WALKER, G. T. (1923). Correlation in seasonal variations of weather. VIII. A preliminary study of world-weather. Memoirs of the Indian Meteorological Department 24(Part 4) 75–131.
These papers by Walker were not discussions of El Niño, however. The link between El Niño and the Southern Oscillation wasn’t established until the 1960s. Therefore, the word oscillation in Southern Oscillation does not apply to El Niño and La Niña events or their processes. It only applies to the impacts of El Niño and La Niña on the sea level pressures in Tahiti and Darwin, Australia.
The sequence of papers and the advancement in ENSO research is further described in Rasmussen and Carpenter (1982).
Then there’s the term “ENSO Cycle”. The NOAA Climate Prediction Center (CPC) and many others, including me, use the phrase to describe El Niño and La Niña events and the variations from one state to the other. Refer to the CPC’s wonderful series of ENSO-related web pages ENSO Cycle that we’ll use for further discussions in Chapter 4.14 Impacts of ENSO Events on Regional Temperature and Precipitation.
DEFINITIONS OF OSCILLATION AND CYCLE
The Wikipedia definition of Oscillation begins:
Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states.
El Niño and La Niña events do not repeat in time, there are very few things that are repetitive in ENSO, so by this definition, ENSO isn’t a true oscillation. In fact, Wikipedia writes in their initial description of El Niño-Southern Oscillation.
El Niño/La Niña-Southern Oscillation, or ENSO, is a quasiperiodicclimate pattern that occurs across the tropical Pacific Ocean roughly every five years.
Oscillation is much easier to write than “quasiperiodic climate pattern”. To add confusion, “pattern” has multiple meanings. It could be used as “pattern in time”, or to describe a “spatial pattern”, as in the warming or cooling of the central and eastern equatorial Pacific.
Webster has a number of definitions for the word cycle. The one that fits ENSO best is:
1: a recurring series of events: as…
c : a series of ecological stages through which a substance tends to pass and which usually but not always leads back to the starting point <the cycle of nitrogen in the living world>
Because an El Niño event does not always lead to a La Niña event and because La Niña events can be followed by another independent La Niña event, this definition of cycle under “c” is applicable to ENSO.
The term Southern Oscillation is used to represent the effects of El Niño and La Niña on the sea level pressure of the off-equatorial South Pacific. We’ll discuss it further in Chapter 4.3 ENSO Indices. Also discussed in that chapter, there’s another widely used ENSO index. It represents the effects of El Niño and La Niña events on the sea surface temperature anomalies of the equatorial Pacific region called NINO3.4, which is bounded by the coordinates of 5S-5N, 170W-120W. The Southern Oscillation Index and NINO3.4 sea surface temperature anomalies do NOT represent the process of ENSO. They are used only to indicate the frequency, strength and duration of El Niño and La Niña events. They indicate nothing more. They do not represent the process of ENSO, only its effect on the variable being measured for the index.
RECAP
El Niño-Southern Oscillation and ENSO Cycle are convenient phrases used to describe El Niño and La Niña. El Niño and La Niña events are not repetitive in time so they are not true oscillations. If it’s understood that an ENSO cycle may not lead to another series of El Niño and La Niña events nor even lead to the opposite phase, then cycle is applicable.
It’s a lot easier to write El Niño-Southern Oscillation than it is to write El Niño-La Niña/Sea Level Pressure Difference Between Darwin and Tahiti Quasiperiodic Climate Pattern.
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CHAPTER 4.17: ENSO – A CYCLE OR SERIES OF EVENTS?
If you were to Google ENSO and cycle, you’d get over 700,000 results. Limit your search to Google Scholar and there are more than 39,000 results. Place “ENSO cycle” in quotes and there’s almost 5,800. One of the reasons: ENSO stands for El Niño-Southern Oscillation and oscillation implies cyclical behavior. Another reason: the delayed oscillator theory suggests that one phase leads to the next, and that sure sounds like a cycle. However, is ENSO really a cycle?
The need to treat ENSO as a cycle arises from the attempts to model ENSO with computers. Mother Nature, however, apparently isn’t concerned about our ability to model it. While parts of ENSO act as a cycle, the evolution of an El Niño event requires a basically random event to initiate it. Therefore, to answer the title question of this chapter, ENSO is a combination of the two.
Kessler (2002) Is ENSO a cycle or a series of events? discusses how observational data suggest that El Niño events are event-like disturbances, while other phases display the behavior of a cycle. The abstract reads:
After early ideas that saw El Niños as isolated events, the advent of coupled models brought the conception of ENSO as a cycle in which each phase led to the next in a self-sustained oscillation. Twenty-two years of observations that represent the El Niño and La Niña peaks (east Pacific SST) and the memory of the system (zonal-mean warm water volume) suggest a distinct break in the cycle, in which the coupled system is able to remain in a weak La Niña state for up to two years, so that memory of previous influences would be lost. Similarly, while the amplitude of anomalies persists from the onset of a warm event through its termination, there is no such persistence across the La Niña break. These observations suggest that El Niños are in fact event-like disturbances to a stable basic state, requiring an initiating impulse not contained in the dynamics of the cycle itself.
When studying this subject and looking for additional papers, it is important to isolate discussions of models and the efforts being taken to improve them. Models are not reality. They are attempts to simulate Mother Nature with computers. The discussion of whether ENSO is a cycle or a series of events is an observations-based discussion. Some of the model-based papers do include discussions of observations, but you have to make sure you’re basing your understandings of ENSO on the observations and not the models in those papers. That pretty much holds true for all climate and climate change papers.
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THE REST OF THIS SERIES
The remainder of this series of posts will be taken from the following myths and failed arguments. They’re from Section 7 of my book Who Turned on the Heat? I may select them out of the order they’ve been presented here, and I’ll try to remember to include links to the other posts in these lists as the new posts are published.
A New Myth – ENSO Balances Out to Zero over the Long Term
Failed Argument – El Niño Events Don’t Create Heat
Myth – ENSO Has No Trend and Cannot Contribute to Long-Term Warming
Myth – The Effects of La Niña Events on Global Surface Temperatures Oppose those of El Niño Events
Myth – El Niño Events Dominated the Recent Warming Period Because of Greenhouse Gases
Myth – ENSO Only Adds Noise to the Instrument Temperature Record and We Can Determine its Effects through Linear Regression Analysis, Then Remove Those Effects, Leaving the Anthropogenic Global Warming Signal
Myth – The Warm Water Available for El Niño Events Can Only be Explained by Anthropogenic Greenhouse Gas Forcing
Myth – The Frequency and Strength of El Niño and La Niña Events are Dictated by the Pacific Decadal Oscillation
And I’ll include a few of the failed arguments that have been presented in defense of anthropogenic warming of the global oceans.
Failed Argument – The East Indian-West Pacific and East Pacific Sea Surface Temperature Datasets are Inversely Related. That Is, There’s a Seesaw Effect. One Warms, the Other Cools. They Counteract One Another.
INTERESTED IN LEARNING MORE ABOUT THE EL NIÑO AND LA NIÑA AND THEIR LONG-TERM EFFECTS ON GLOBAL SEA SURFACE TEMPERATURES?
Why should you be interested? Sea surface temperature records indicate El Niño and La Niña events are responsible for the warming of global sea surface temperature anomalies over the past 30 years, not manmade greenhouse gases. I’ve searched sea surface temperature records for more than 4 years, and I can find no evidence of an anthropogenic greenhouse gas signal. That is, the warming of the global oceans has been caused by Mother Nature, not anthropogenic greenhouse gases.
I’ve recently published my e-book (pdf) about the phenomena called El Niño and La Niña. It’s titled Who Turned on the Heat? with the subtitle The Unsuspected Global Warming Culprit, El Niño Southern Oscillation. It is intended for persons (with or without technical backgrounds) interested in learning about El Niño and La Niña events and in understanding the natural causes of the warming of our global oceans for the past 30 years. Because land surface air temperatures simply exaggerate the natural warming of the global oceans over annual and multidecadal time periods, the vast majority of the warming taking place on land is natural as well. The book is the product of years of research of the satellite-era sea surface temperature data that’s available to the public via the internet. It presents how the data accounts for its warming—and there are no indications the warming was caused by manmade greenhouse gases. None at all.
Who Turned on the Heat?was introduced in the blog post Everything You Every Wanted to Know about El Niño and La Niña… …Well Just about Everything. The Updated Free Preview includes the Table of Contents; the Introduction; the beginning of Section 1, with the cartoon-like illustrations; the discussion About the Cover; and the Closing. The book was updated recently to correct a few typos.
Please buy a copy. (Credit/Debit Card through PayPal. You do NOT need to open a PayPal account.). It’s only US$8.00.
VIDEOS
For those who’d like a more detailed preview of Who Turned on the Heat? see Part 1 and Part 2 of the video series The Natural Warming of the Global Oceans. Part 1 appeared in the 24-hour WattsUpWithThat TV (WUWT-TV) special in November 2012. You may also be interested in the video Dear President Obama: A Video Memo about Climate Change.
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Your contribution to our scientific understanding of ENSO and related matters is huge, Mr. Tisdale. You are attempting to change the focus of modelers and so-called climate scientists and to place that focus on the physical processes that make up ENSO. Reminds me of Galileo. And you are right. There will be no understanding of ENSO until there is serious empirical research on the underlying and mostly unknown physical processes that make it up.
Bob Tisdale says:
December 4, 2012 at 8:05 am
…And you got me with mug to face. Nothing better than a good sinus wash with coffee.)
Just trying to help, Bob – sinus health is sadly neglected these days ;).
If it’s understood that an ENSO cycle may not lead to another series of El Niño and La Niña events nor even lead to the opposite phase, then cycle is applicable.
It looks like what you have is a cyclic process (such as that clearly shown in Figure 1) in which the highs sometimes do not get classified as “El Niño” and the lows sometimes do not get classified as “La Niña”. Is this something more than a debate or a confusion about where to draw the line to declare “El Niño” and where to draw the line to declare “La Niña”? What you have described is less secure for declaring something “present” vs. that same thing “absent” than, say, deciding whether an electron is “present” or “absent”, or a proton is “present” or “absent”.
What you have described is more like deciding the hematocrit of blood satisfies the criteria for accepting a donation than it is like typing A, B, and Rh.
Satellite trends versus tide gaude trends:
The “explaination” of higher satellite trends with trade winds leading to higher sea level rises in open sea is not valid.
For an increase, there have to be ADDITIONAL trade winds to form that deviation. and those ADDITIONAL trade winds would have had to be sustained for many years and just have started in the year when the satellite record started.
But thats not all, additional trade winds would have to blow from coast to open sea anywhere in the world and not from east to west.
It is much more safe to assume, that satellite trends are inflated and tide gauge data are correct.
Bart says:
December 3, 2012 at 10:55 pm
Clyde says:
December 3, 2012 at 9:42 pm
It’s a very good question, and nice of you to phrase it as you do. I believe the answer is that it is relatively warm water. Not really warm, but warmer than what rose up previously.
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Thanks for the kind reply.
Bob Tisdale says:
December 4, 2012 at 3:36 am
Clyde, your December 3, 2012 at 9:42 pm comment appears to include questions about thermohaline circulation or meridional overturning circulation. Unfortunately, they’re topics not often discussed here at WUWT, but you may get lucky and find someone with backgound in those processes to answer your questions.
Regards
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I was told to look into thermohaline circulation. I guess if i don’t see a post on here (hint hint Mr Watts) I’ll see if i can find somebody to explain it in simple terms.
Thanks for the kind reply.
trafamadore says:
December 3, 2012 at 6:18 pm
Oh. Here we go again. Where does the energy come from to raise the temperature? The fish?
You used the word “heat” 6 times in your post, 5 times in “who turned on the heat”.
Is it possible that you can actually believe that the climate system is 100% passive?
That the oceans have negligible heat capacity?
That ocean-atmosphere dynamics have no complexity and are always at 100% equilibrium?
Well I guess that if your co-religionist David Graber can assert for the AGW community that “humans became a cancer on the earth one billion years ago” [sic] then, well, anything is possible.
This post explains briefly why energy increases in the atmosphere from ENSO over many years and how ENSO changes to lose energy over many years. A 4 percent increase in global low cloud levels will put the Earth back to global temperatures of the 1970′s. Anyone dismissing solar warming without even considering this important observation of the period is down to ignorance.
Notice El Nino’s roughly got stronger during the period while global low cloud albedo was declining. Since 2006 low global cloud has stopped declining therefore based on the ENSO knowledge so far future El Nino’s will not be stronger than the 1997/98 one unless a further decrease in global low cloud albedo occurs in future. Therefore based on what’s been happening recently El Nino’s should become stable/weaker and any increases in global low cloud albedo in future will further weaker them. The process of ENSO moving warm surface water around the globe towards the pole will be reduced and therefore rises in global temperatures also reduced. This will then lead to peaks and troughs in the ENSO swings at lower levels than compared over the recent warm period.
This is because when the solar activity reached an increased level during the 1950′s the trade winds were generally strong over this period right through to mid 1970′s. These resulted in plenty of up welling ocean water and warming ocean water from the sun was piled towards the western side of the Pacific Ocean circling to greater depths. This resulted in energy not calculated in surface temperatures because it was below the surface and not allowed to spread east over the ENSO surface region. Data during this period in the ocean depths were very limited so missed this increased energy around the western areas of the Pacific Ocean.
Post 1970′s the trade winds declined for longer periods especially beginning with the Pacific shift and moderate/strong El Nino in the early 1980′s. This resulted in the warmed sub-ocean water that had not been calculated over the recent decades surface temperatures, (1950/1960′s etc) surfacing across the central and eastern Pacific and warming global temperatures in it’s wake. This process delayed the warming from the increased solar cycle until the trade winds become weak and allowed warmer water to form much more over the surface and be eventually lost by the atmosphere. Suddenly this warmed the planet from the tropics to the poles via the process of ENSO.
Summary
ENSO contributes towards warming of the atmosphere over the past few decades by moving and allowing energy build-up on the surface instead of downwelling in the western Pacific ocean. The trade winds determine the difference between moving energy to the surface and down-welling in western regions with central and eastern ocean regions upwelling over a long period. Down-welling removes energy from the surface and prevents it’s loss from the atmosphere. Upwelling in central and eastern regions of the Pacific ocean prevent solar warming of the surface from building up and pooling. Low cloud albedo determines how much the sun warms the ocean surface in making the next ENSO event stronger or weaker. Weak trade winds generally favour El Nino’s and strong trade winds La Ninas.
Bob, being a complete neophyte on this subject, your description of a cyclic but non periodic interaction reminds me of looking at the surface of a heated pot of water prior to coming to a boil, There are swirling patterns on the surface that are certainly cyclic but non-periodic and completely unpredictable. Like the Kelvin-Helmholtz Instability, I’m sure the process can be modeled with CFD software in a general way to produce similar looking patterns but such models are totally useless in predicting what will be going on at any specific point in an actual specific pot of water because the process is chaotic in nature. Am I on the right track in understanding what you are trying to get across?
The ENSO is well described as a nonlinear oscillator as has been discussed here several times, and indeed as Bob alludes to in his delayed oscillator theory in his ENSO book.
Here is an article on chaotic / nonlinear dynamics that nicely illustrates the Lorenz attractor characteristic of such systems:
http://www.gweep.net/~rocko/sufficiency/node10.html
Have a look at the X and Y plots, with alternating phases with high cycles and low cycles (e.g. fig 4.1, 2.7). Then consider periods of alternating dominance of el Nino and La Nina? Can one discern a pattern or a connection here?
Jester Via: I don’t believe that I’d categorize in that fashion. The “normal” state of the tropical Pacific is dictated by the interaction between trade winds and the temperature gradient between the eastern and western tropical Pacific, where it’s about 7 to 9 deg C cooler in the east than it is in the west. The trade winds draw cool water from below the surface in the east, along the equator. The temperature gradient is caused by the sun warming that cool water as it travels from east to west, driven by the trade winds. But the trade winds are driven by the temperature gradient. That is, because the water’s warmer in the west, there’s more convection there, causing the air to rise. The trade winds make up the deficit caused by the rising air. At altitude, the air cools as it travels east and then drops in the eastern Pacific, completing the loop (called a Walker cell). There’s positive feedback between the temperature gradient and the trade winds (called Bjerknes feedback).
Back to the warm water traveling from east to west: That wind-driven, sun-warmed water runs into land in the western tropical Pacific and “piles up” there, so it’s physically higher in the west than in the east. The warmer water is held in place by the trade winds, but gravity wants to level the playing field. The trade winds, temperature gradient and gravity all interact, all balancing against one another. With the positive feedback, that state will exist until something throws it out of balance.
Then, along comes a weather event like a tropical cyclone in the western Pacific, which disrupts the balance by slowing the trade winds. If the trade winds weaken enough and the weakening lasts long enough, gravity will win and the warm water in the west will slosh east (the initial wave is called a Kelvin wave) and an El Niño will start.
That of course assumes there’s enough warm water in the western tropical Pacific to support an El Niño. This year there wasn’t a whole lot of warm water so this El Niño isn’t very strong. But a year before the start of the 1997/98 El Niño, there were unusual weather conditions during the 1995/96 La Niña, which pushed aside the cloud cover and allowed the sun to create a bunch of warm water. The end result was the 1997/98 super El Niño.
On the other side of the coin are La Niña events, which replenish the warm water released by the El Niño before it. During a La Niña, the trade winds are stronger than normal, resulting in less cloud cover and more sunlight warming the ocean to depth. The stronger trade winds blow the warm water to the west, where it again accumulates in the western tropical Pacific. (Recharging the capacitor, the west Pacific Warm Pool, for the next discharge during an El Niño.)
Hmmm, looks like a rambled on there, but each time I explain the basic process, I present it a little differently and it helps everything click for someone else.
Also note, that explanation doesn’t include the warm water that’s left over after the El Niño, which climate scientists overlook.
Matthew R Marler says: “It looks like what you have is a cyclic process (such as that clearly shown in Figure 1) in which the highs sometimes do not get classified as ‘El Niño’ and the lows sometimes do not get classified as “La Niña”. Is this something more than a debate or a confusion about where to draw the line to declare ‘El Niño’ and where to draw the line to declare “La Niña”?”
The variations taking place in the tropical Pacific are typically classified as an El Niño when the sea surface temperature anomalies in the NINO3.4 region rise above a threshold of +0.5 deg C and as a La Niña event when they drop below the threshold of -0.5 deg C.
BUT, big but, relying solely on an index gives the wrong impression of what’s taking place and does not recognise the differences between El Niños and La Niñas.
A La Niña is simply an exaggeration of the normal state of the tropical Pacific. During a La Nina, there are stronger trade winds, more upwelling of cool water in the eastern equatorial Pacific, less cloud cover and more sunlight entering and warming the tropical Pacific waters as they travel from east to west.
On the other hand, during an El Niño, the state of the tropical Pacific changes: The Equatorial Countercurrent in the tropical Pacific engorges and carries much more warm water than normal from west to east, flooding the central and eastern tropical Pacific with warmer-than-normal warm water. (It’s warmer than normal because the water in the western tropical Pacific is typically 7-9 deg C warmer than in the east during ENSO-neutral and La Niña conditions.) The trade winds in the western tropical Pacific reverse and become westerlies, and the convection/cloud cover/precipitation accompany the warm water to the east, which disrupts the atmospheric circulation patterns globally.
I think I’ve got what is being said. There has been no global warming. It is just a matter of a redistribution of heat. Or is it the clouds?
Bob –
I’m sure you must be aware of this, but it is the case that average global temperature since 1958 [the start of the Mauna Loa CO2 series] is a very interesting match for a linear scaling of the monthly MEI [multi-variate El Nino index] when accumulated. I was looking for something a little more complex than this when I stumbled on it some time ago. So, the people arguing that a cyclical ENSO would not impact the climate would be right: but the fact is, that during the period of rising temperature from the 70’s to 1998, the MEI index was more positive than negative. Since then El Nino/La Nina has been in balance, and temperature is flat. Have you any comment on this?
Hi RERT: You wrote/asked: “Since then El Nino/La Nina has been in balance, and temperature is flat. Have you any comment on this?”
Bob Tisdale explains this in simple to understand detail. I believe you will find a clear answer to your question here:
izen: The links you provided are to paleoclimatological reconstructions—aka make-believe data—not instrument-measured temperature data. Before you provided those links, you even quoted what I replied to you earlier, which was “Please provide a link to the dataset that presents the instrument-based temperature measurements for ‘several thousand years of ENSO’.”
Wanna try again, izen? You’re going to have trouble responding because there was little ship traffic across the eastern equatorial Pacific before the opening of the Panama Canal in 1914.
With respect to the earlier part of your reply, izen, I’ll be happy to show you and everyone else reading this thread why you’re incorrect. The following three graphs are from an upcoming post. It’s a blog memo to John Hockenberry about some sleight of hand in the PBS special “Climate of Doubt”.
The data does, in fact, account for its warming. Here’s a color-coded graph of the sea surface temperature anomalies for the Atlantic, Indian and West Pacific Oceans, which I’ve identified as the rest of the world (as opposed to the East Pacific). The periods in red highlight the responses of the sea surface temperatures for the Rest-of-the World to major El Niño events. The graph clearly shows that the data warmed only during those El Niño events:
http://i46.tinypic.com/r1a1vp.jpg
We can confirm that by removing the rises in sea surface temperature associated with those El Niño events. Without those responses to the El Niño events, the Rest-of-the-World data would not have warmed in 30 years:
http://i45.tinypic.com/2qspjkz.jpg
Why does the Rest-of the-World data warm only during those El Niño events, izen? Because, it very obviously does not cool proportionally during the La Niña events that followed those big El Niños. If it did, the Rest-of-the-World data would look similar to the East Pacific data, which shows no warming for the past 30 years:
http://i48.tinypic.com/flkhmb.jpg
Mike Wryley says:
December 3, 2012 at 8:12 pm
Here in the midwestern US we continue to be in a dry weather pattern, and we need some serious rain in the coming months…..
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North Carolina needs some serious rain too. Mostly our rain comes from the west over the Appalachians so if you are dry so are we. Unless of course we get plastered by a hurricane.
Thank you again Bob for your videos. They were very clear and informative.
@trafamadore: You wrote: “You have the sloshing about part right, but you have failed to do the math. And in the end, that’s the real deal. Why don’t you just do it and present it in a simple table?”
Response: You might not understand the IPCC models, which you reference above. You certainly admit you cannot look at answers provided to your own questions because the answers might be more complex than you would like. We on this blog are willing to help, but do not appreciate sarcastic condescension. My advice is to seek to learn from people who understand the complex and can explain it in simple terms.
The IPCC models have largely and continually predicted things which did not happen. Their models continually change as real data present a different outcome. By chance, some of their dozens of model outcomes have been close… but most of them are simply way wrong. And the wrong models are used for Policy makers to tax carbon!!! I assume you do not know this, which is why I have spent the time to let you know. You could find the projections of their models in earlier IPCC reports, but then again, I assume that you will not, since it’s not simple to know the truth for you.
I have one question: Since you are unwilling to actually look at information, where is it that you get your ideas from?
Mario
Bob Tisdale: A La Niña is simply an exaggeration of the normal state of the tropical Pacific. … .
On the other hand, during an El Niño, the state of the tropical Pacific changes: The Equatorial Countercurrent in the tropical Pacific engorges and carries much more warm water than normal from west to east, flooding the central and eastern tropical Pacific with warmer-than-normal warm water.
How can you tell that the El Niño does not emerge from an oscillatory process, or a set of oscillatory processes?
Do you know what causes an El Niño to occur? If that’s in your other writing or your book, I’ll go there. Here you make it sound like an agent that happens to act on its own, or a process that starts without prompting.
Bob, Thanks for the more detailed explanation. What you described is similar to what I would call a relaxation oscillator, a type of electronic oscillator that has relatively poor spectral purity due to the influence of noise. As the capacitor charges, it approaches an unstable situation, a tipping point, where a switch will suddenly trip and discharge the capacitor. Any noise present influences the exact moment it switches. The noise, in this case, can be some extreme weather event and large enough that it can cause the switch before much energy is stored in the capacitor, making the discharge a less noticeable event. Additionally, even the charge rate of the capacitor is weather dependent making the repetition rate even less of a periodic function.
Bob, After watching your video, I find a flaw in my relaxation oscillator analogy. The capacitor never charges to the tipping point but only charges to just under the tipping point and sits there until triggered by some event. That charged state is the ENSO – neutral state waiting to be triggered like a mousetrap.. Now I understand why you say it isn’t an oscillator at all.
@Arno: You wrote: “Arno Arrak says: “I hate to tell you but you are dead wrong. I proved that it is cyclical in my book ‘What Warming? Satellite view of global temperature change’ already two years ago”
The fact that you wrote a book, does not lend you credence. Illustrating an understanding of complex systems does not seem like your forte’. You did a fine job using elementary science to describe that wind blows water in one direction, and that it has to go back eventually. Then you go into detail explaining how wind blows water. Your description does not offer a valid argument against what Tisdale shows in detail.
Perhaps it’s semantics to you, or you can’t stand the idea that someone else sheds light on an area of science that antiquates your simplistic description of how wind blows water.
Mario:
Perhaps to a layperson, but it’s a bit more complex than that as used in science. A system like x = cos(2*pi*3*t) + cos(2*pi*5*t) is clearly oscillatory, but you don’t have strict “up and down” behavior.
Bart:
It’s a spectral periodogram. I averaged it to make it smooth (this just beats down the “whiskers”) The peaks look a bit funky compared to what you’re used to, because I computed the transform in frequency space then mapped it in to period = 1/f. At least over the period I’ve looked at (1950-now), this result seems very robust.
I’ve seen efforts to do both of these today at the AGU meeting–somebody was using KF to study the effect of solar forcing on the temperature field. I saw somebody else examining Kelvin waves (which of course are related to ENSOs).
I would think this particular system would be very amenable to KF. My suspicion is one could develop a framework (two coupled modes) that had some real forecast skill.
Bob Tisdale:
The fact you see peaks at 3 and 5 years tells you that there’s coherent energy in narrow frequency bands about these frequencies. That’s what lets us call it oscillatory. If the frequency bands went to zero as you increased the temporal window, we’d go further and call it “fixed frequency oscillation” or FFO.
If the frequencies have a finite width (and no visible subharmonics) we would conclude the process is “quasi-periodic”. The source of the nonstationary behavior seen here isn’t probably well understood but the main prediction of having two frequency peaks at 3 and 5 years is that you don’t get a simple progression between El Niños and La Niñas.
If I understand it right, that’s the real point you’re making in any case (in any case it’s an important regardless of whether 9 of 10 scientists would still call the system “cyclic”).
Carrick: You missed my point. Physically, they’re independent events.
Lester Via: Pardon my misspelling of your name in my December 4, 2012 at 1:45 pm comment.
RERT says: “I’m sure you must be aware of this, but it is the case that average global temperature since 1958 [the start of the Mauna Loa CO2 series] is a very interesting match for a linear scaling of the monthly MEI [multi-variate El Nino index] when accumulated.”
Using a running total of HADISST-based NINO3.4 seas surface temperature anomalies with base years of 1950-79 as the ENSO index, you can recreate the underlying global temperature anomaly curve as far back as the 1910s. Refer to:
http://bobtisdale.wordpress.com/2009/01/25/reproducing-global-temperature-anomalies-with-natural-forcings/
RERT says: “Since then El Nino/La Nina has been in balance, and temperature is flat. Have you any comment on this?”
The leftover warm water from the 2009/10 El Niño may have caused a minor upward shift in the sea surface temperature anomalies of the Atlantic-Indian-West Pacific oceans (90S-90N, 80W-180). It’s a bit early to tell, though.
http://bobtisdale.files.wordpress.com/2012/11/4-row.png
The reason I say “may have caused” is that there was an unusual surge in South Atlantic sea surface temperatures around the same time…
http://bobtisdale.files.wordpress.com/2012/11/8-so-atl.png
…and I suspect that helped cause a secondary surge in the sea surface temperatures of the North Atlantic shortly afterwards. But it’s difficult to tell with the North Atlantic data because it’s so volatile:
http://bobtisdale.files.wordpress.com/2012/11/7-no-atl.png