La Nina – The Underappreciated Portion Of ENSO
Guest post by Bob Tisdale
Perform a Google Scholar search for documents including “El Nino” in quotes and there will be more than 200,000 results. On the other hand, “La Nina” will only raise 26,000+. Granted, the formal name of the coupled ocean-atmosphere phenomenon in the tropical Pacific is “El Nino-Southern Oscillation”, but that in quotes only returns 28,000+ results. So it appears that El Nino events do get much more “press” from the scientific community than La Nina events.
Figure 1 is a time-series graph of NINO3.4 SST anomalies from January 1979 to January 2010. El Nino events are a warming of the central and eastern tropical Pacific so they are displayed as a Positive SST anomaly, where La Nina events are a Negative. Visually, is the eye drawn to the upward spikes more than it is to the downward troughs? El Nino events are viewed as being larger in magnitude than La Nina events. NINO3.4 SST anomalies peaked at approximately 2.8 deg C during the Super El Nino events of 1982/83 and 1997/98, while the La Nina events that followed them failed to reach -2 deg C. But the La Nina events of 1988/89 and 2007/08 were stronger than the El Nino events that preceded them. (Refer to the note about base years at the end of this post.)
http://i48.tinypic.com/dpikxz.png
Figure 1
El Nino events release heat from the tropical Pacific, and through ocean currents and changes in atmospheric circulation, they raise surface temperatures outside of the tropical Pacific. These upward spikes in global temperatures, Figure 2, call attention to El Nino events during periods when global temperatures are rising. During La Nina events, the tropical Pacific releases less heat than normal, and global temperatures decline, which doesn’t have the same visual impact.
http://i45.tinypic.com/28wjsdy.png
Figure 2
La Nina events are a vital portion of the El Nino-Southern Oscillation coupled ocean-atmosphere process. La Nina events recharge the heat released from the tropical Pacific during the El Nino. Figure 3 is a graph of Tropical Pacific Ocean Heat Content compared to scaled NINO3.4 SST anomalies. Note that most La Nina events do not fully recharge the heat released by the El Nino events. From 1976 to 1994, tropical Pacific Ocean Heat Content dropped almost continuously, with occasional major dips and rebounds as an El Nino discharged heat and the subsequent La Nina partially recharged it. Then, the 1995/96 La Nina event, one that was not particularly strong, replaced all of the heat that had been released (plus some) over that 18-year stretch.
http://i46.tinypic.com/2vja1z5.png
Figure 3
THE 1995/96 LA NINA PROVIDED THE FUEL FOR THE NEXT EL NINO
During a La Nina event, tropical Pacific trade winds rise above normal levels. The increase in trade winds reduces cloud cover. Reduced cloud cover allows more Downward Shortwave Radiation (visible light) to warm the tropical Pacific. These coupled ocean-atmosphere processes associated with La Nina events were discussed in the post More Detail On The Multiyear Aftereffects Of ENSO – Part 2 – La Nina Events Recharge The Heat Released By El Nino Events AND…During Major Traditional ENSO Events, Warm Water Is Redistributed Via Ocean Currents”.
As noted above, the 1995/96 La Nina was not a strong event, yet it recharged all of the ocean heat that had been released in almost two decades of El Nino events. In “Genesis and Evolution of the 1997-98 El Niño” [ Science 12 February 1999: Vol. 283. no. 5404, pp. 950 – 954, DOI:10.1126/science.283.5404.950], Michael McPhaden explains, “For at least a year before the onset of the 1997–98 El Niño, there was a buildup of heat content in the western equatorial Pacific due to stronger than normal trade winds associated with a weak La Niña in 1995–96.” Link to Science abstract:
http://www.sciencemag.org/cgi/content/abstract/283/5404/950
Link to NOAA copy of McPhaden (1999):
http://www.pmel.noaa.gov/pubs/outstand/mcph2029/text.shtml
So there was a short-term recharge of tropical Pacific Ocean Heat Content in 1995/96, which is very evident in Figure 3. And this short-term buildup of heat content provided the fuel for the 1997/98 El Nino. Contrary to the beliefs of anthropogenic warming proponents the 1997/98 El Nino was NOT fueled by a long-term accumulation of heat from manmade greenhouse gases.
AND THAT 1997/98 EL NINO WAS CALLED THE EL NINO OF THE CENTURY
The 1997/98 El Nino was strong enough to temporarily raise Global Lower Troposphere Temperature anomalies ~0.7 deg C, as illustrated in Figure 4. Note: The period of 1995 to present was used in the following graphs because there have been no explosive volcanic eruptions since 1995 to add unwanted noise to the data.
http://i47.tinypic.com/21nnu4z.png
Figure 4
And referring to Figure 5, Lower Troposphere Temperature anomalies of the Mid-To-High Latitudes of the Northern Hemisphere rose, but remained at elevated levels that varied well above the value in late 1996. This upward step (and a similar but smaller one caused by the 1986/87/88 El Nino) was discussed in the post “RSS MSU TLT Time-Latitude Plots…Show Climate Responses That Cannot Be Easily Illustrated With Time-Series Graphs Alone”.
http://i48.tinypic.com/33p6nbn.png
Figure 5
Sea Surface Temperature anomalies for the Mid-To-High Latitudes of the Northern Hemisphere also rose and remained at an elevated level. Refer to Figure 6, which compares that dataset to scaled NINO3.4 SST anomalies. The latitudes used for the SST anomalies in this illustration are 20N-65N, which are latitudes that have little impact from polar ice. This upward step in the Sea Surface Temperature anomalies for the Mid-To-High Latitudes of the Northern Hemisphere will be discussed in a future post. I have, however, discussed the impacts of El Nino events on the North Atlantic in the post There Are Also El Nino-Induced Step Changes In The North Atlantic. And the North Atlantic is also impacted by the Atlantic Multidecadal Oscillation, but that appears to have peaked in 2005.
http://i46.tinypic.com/2ylpix3.png
Figure 6
And for those wondering how well the SST and TLT anomalies for the Mid-To-High Latitudes of the Northern Hemisphere correlate, I’ve prepared Figure 7. The SST anomaly data were scaled by a factor of 1.8. There are divergences from year to year, but keep in mind that the coverage areas are very different; the TLT anomalies also include data over continental land masses. One thing is certain; the 1997/98 El Nino caused upward steps in both datasets.
http://i49.tinypic.com/2uo2o8y.png
Figure 7
And there are the impacts of the 1997/98 El Nino on the East Indian and West Pacific Oceans (60S-65N, 80E-180), which I first discussed in a series of posts more than a year ago. The 1997/98 El Nino shifted Sea Surface Temperature anomalies upward in this area of the global oceans, too. Refer to Figure 8. The cause of this was discussed in the posts Can El Nino Events Explain All of the Global Warming Since 1976? – Part 1 and Can El Nino Events Explain All of the Global Warming Since 1976? – Part 2.
http://i48.tinypic.com/2qamu88.png
Figure 8
Basically, the warm water that was built up during the 1995/96 La Nina collected below the surface of an area in the western tropical Pacific known as the Western Pacific Warm Pool (to depths of 300 meters). During the 1997/98 El Nino, the warm water contained in the Western Pacific Warm Pool sloshed east and spread across the surface of the central and eastern tropical Pacific. The warmer-than-normal waters raised Sea Surface Temperatures and changed atmospheric circulation. Then, as the La Nina of 1998/99/00/01 progressed, the trade winds, Pacific Equatorial Currents, and a phenomenon known as a Rossby wave returned the remaining surface and subsurface warm water to the western Pacific. Some of the warm water returned to the Pacific Warm Pool, but a major portion of it remained on the surface and was redistributed by ocean currents to western North and South Pacific, and a portion of the warm water migrated to the Eastern Indian Ocean.
BLAME THE 1995/96 LA NINA FOR THE RECORD TEMPERATURES DURING THE 2000s AND IN 2010
So, if you’re wondering why the present moderate El Nino event of 2009/10 is raising global temperatures to record levels, you have to go back in time. The 1995/96 La Nina provided the build-up of warm waters that was then discharged by the 1997/98 El Nino and redistributed by the 1998/99/00/01 La Nina. The end results were upward steps in SST anomalies and TLT anomalies for major portions of the globe.
One of the methods anthropogenic global warming advocates (scientists and bloggers) use to illustrate the assumed effects of greenhouse gases on global temperatures is to illustrate the divergence between the linear trends of global temperatures and a scaled ENSO index such as NINO3.4 SST anomalies. Refer to Figures 9 and 10. But the upward steps illustrated in Figure 5 and 6 bias global temperature data upwards.
http://i46.tinypic.com/2vsl2mr.png
Figure 9
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http://i50.tinypic.com/2d7j0ux.png
Figure 10
And the biases created by those step changes in the SST and TLT anomalies of the Mid-To-High Latitudes of Northern Hemisphere are responsible for much of the differences between NINO3.4 SST anomalies and global temperature anomalies. We can illustrate this looking at the data for the rest of the world; that is, by comparing the linear trend of NINO3.4 SST anomalies with the linear trends the TLT and SST anomalies for the tropics and the Mid-To-High Latitudes of the Southern Hemisphere. Refer to Figures 11 and 12. As shown, the linear trends of the NINO3.4 SST anomalies are slightly negative, but the linear trends for the SST and TLT anomalies of the tropics and Mid-To-High Latitudes of the Southern Hemisphere are relatively flat–much flatter than the global datasets.
http://i50.tinypic.com/vsn97q.png
Figure 11
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http://i49.tinypic.com/11mcj7p.png
Figure 12
That would mean the ENSO-induced step increases in SST and TLT anomalies of the Mid-To-High Latitudes of the Northern Hemisphere caused the vast majority of the positive linear trends for the global SST and TLT anomaly datasets. See Figures 13 and 14, which show the strengths of the positive trends for those areas of the globe.
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Figure 13
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Figure 14
Figures 15 and 16 compare the SST and TLT anomalies for the Mid-To-High Latitudes of the Northern Hemisphere to the Global data and to the SST and TLT anomalies for the Mid-To-High Latitudes of the Southern Hemisphere. It should now be clear that the majority of the rises in Global SST and TLT anomalies since 1995 were caused by the 1997/98 El Nino-induced upward steps in the SST and TLT anomalies for the Mid-To-High Latitudes of the Northern Hemisphere.
http://i50.tinypic.com/33p64k1.png
Figure 15
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http://i47.tinypic.com/1zywv8k.png
Figure 16
In short, the effects of the La Nina- and El Nino-induced step changes in the SST and TLT anomalies of Mid-To-High Latitudes of the Northern Hemisphere are mistaken for, and misrepresented as proof of, anthropogenic global warming.
A BRIEF LOOK AT AN EARLIER LA NINA EVENT
The 1972/73 El Nino was a strong ENSO event. NINO3.4 SST anomalies, referring to Figure 17, peaked above 2 deg C. There were only two El Nino events stronger than the 1972/73 El Nino in the second half of the 20th Century, and they were the two Super El Nino events of 1982/83 and 1997/98.
http://i46.tinypic.com/29krqd2.png
Figure 17
But the 1972/73 El Nino shares another superlative with the 1997/98 El Nino. Both El Nino events were followed by La Nina events that lasted through not one ENSO season, not two ENSO seasons—they lasted through three consecutive ENSO seasons. The La Nina event of 1998/99/00/01 recharged the heat content released by the 1997/98 El Nino and returned the tropical Pacific Ocean Heat Content to the new higher levels established during the 1995/96 La Nina. Refer to Figure 18. The La Nina event of 1973/74/75/76 recharged the heat released from the Tropical Pacific by El Nino events during the decade of the early 1960s to the early 1970s. And it also added to the Tropical Pacific Ocean Heat Content.
http://i46.tinypic.com/2vja1z5.jpg
Figure 18
The Pacific Climate Shift of 1976/77 is a much-studied phenomenon. Trenberth et al (2002) discussed the differences in the evolution of El Nino events before and after the shift, and Trenberth et al (2002) referenced other papers that discussed effects of the Pacific Climate Shift on ENSO. Link to Trenberth et al (2002):
http://www.cgd.ucar.edu/cas/papers/2000JD000298.pdf
El Nino events became stronger after the Pacific Climate Shift. The frequency of El Nino events and El Nino Modoki increased. As noted in an early post, The 1976 Pacific Climate Shift, there were notable shifts in the SST anomalies and linear trends of Pacific Ocean basin subsets.
But I have yet to find a paper that attributes the Pacific Climate Shift of 1976/77 to the La Nina event of 1973/74/75/76 or one that even suggests that the 3-year-long La Nina played a role. Yet through known coupled ocean-atmosphere processes, the 1973/74/75/76 La Nina increased the warm water available for the additional El Nino events after 1976 and for the significant El Nino events of 1982/83 and 1986/87/88.
The explosive volcanic eruption of El Chichon may have counteracted the Super El Nino of 1982/83, but the 1986/87/88 El Nino was strong enough to cause upward shifts in the SST and TLT anomalies of the Mid-To-High Latitudes of the Northern Hemisphere, and the SST anomalies of the East Indian and West Pacific Oceans, similar to the shifts caused by the 1997/98 El Nino illustrated in this post.
A NOTE ABOUT BASE YEARS
Note: The relative strengths of El Nino versus La Nina events discussed early in this post would of course depend on the base years chosen for anomalies. And as illustrated in Figure 17 there is a minor difference depending on whether the base years of 1950 to 1979 or 1979 to 2000 are used. The significance of the difference would depend on how the data is being used. Example: A scaled running total of NINO3.4 SST anomalies will reproduce the basic global temperature anomaly curve as illustrated in Reproducing Global Temperature Anomalies With Natural Forcings if the base years are 1950 to 1979. If the base years of 1979 to 2000 are used, the result will not be similar to the global temperature curve.
http://i47.tinypic.com/2wlrkf4.png
Figure 19
CLOSING COMMENT
The La Nina event of 1973/74/75/76 provided the tropical Pacific Ocean Heat Content necessary for the increase in strength and frequency of El Nino events from 1976 to 1995. The 1995/96 La Nina furnished the Ocean Heat Content that served as fuel for the 1997/98 El Nino. And the 1998/99/00/01 La Nina recharged the tropical Pacific Ocean Heat Content after the 1997/98 El Nino, returning it to the new higher level established by the La Nina of 1995/96.
It would appear that La Nina events do all of the work, while El Nino events get all the glory—and the research.
SOURCE
All data for this post is available through the KNMI Climate Explorer:
http://climexp.knmi.nl/selectfield_obs.cgi?someone@somewhere
Good, fundamental post.
Stephen Wilde (12:16:47): It appears I missed one of your comments in my earlier passes through the thread.
In the comment you posted at 12:16:47 on February 14, you questioned my credibility and the credibility of my post and the credibility of my reference without justification when you wrote, “I can see the points you are making about the recharge process and the way you allocate particular periods of recharge to particular periods of release but some of the examples STRAIN CREDIBILITY.” [My caps for emphasis] Then you confirm that, although you questioned the credibility of my post, you failed to research the matter on your own. You did this with your next group of statements, “In particular a period of recharge that was not particularly strong or lengthy is proposed to have recharged for two decades of El Nino events that were pretty substantial in themselves.”
The data is supported by the McPhaden (1999) reference and the data used in it.
You continued, “Can you be sure that the El Nino / La Nina processes combined are all that is involved here (apart from the sun that is) ?” and “It would explain a lot more if there were variations in the water temperatures coming from the oceanic circulations BEFORE they became involved in the ENSO process. In particular that could provide a plausible connection to the longer term climate and oceanic cycling that I have referred to.”
If there were data to support the possibility that warm waters transferred from another basin, rest assured I would have posted those graphs and illustrated that effect. But to counter your doubts, here’s a graph of the OHC for the mid-to-high latitudes of the North Pacific. No corresponding drop in OHC there in 1995/96.
http://i35.tinypic.com/s3j1h1.png
And here’s a graph of the OHC for the mid-to-high latitudes of the South Pacific. No corresponding drop in OHC there in 1995/96 either.
http://i37.tinypic.com/2vhvkwi.png
And here’s a graph of the Indian Ocean OHC. Once again, there was no corresponding drop in OHC in 1995/96, only a minor rise. The rise in tropical Pacific OHC was not caused by a transfer of warm waters from another basin, Stephen.
http://i45.tinypic.com/zl6s1t.png
But you suggested that the 1995/96 rise in Tropical Pacific OHC may have come from below the 700 meter level, when you wrote, “After all a slightly less cold upwelling entering the ENSO process from below would manifest itself in warming at the surface (and vice versa) and that would help to account for the apparent disjunction between the strengths of the La Nina and El Nino phases in your article.”
You can also rested assured that, back in September, when I first posted the NODC OHC data and noted the anomalous 1995/96 rise in Tropical Pacific OHC, I used another dataset that reaches well below the 700 meter level to verify it. The 1995/96 rise also appears in satellite altimetry-based Sea Level Anomaly data for the Tropical Pacific.
http://i45.tinypic.com/24b2sso.png
Your attempt to discredit me and my post failed, Stephen. Again, you should rely on data instead of speculation.
Bob,
I am not trying to discredit you.
I was simply seeking to bridge the gap between the ENSO process that you describe and the longer term climate cycling that seems to be ocean driven. I have noted your previous comment that you are not interested in that so I have stopped pursuing it with you.
I did not question your credibility. I questioned the credibility of certain assertions. I am unlikely to have been the only reader with similar thoughts and my crystallising them helps you to express your findings more clearly if you respond in a helpful manner. Just referring a less knowledgeable reader to reams of previous work is not especially helpful. I constantly have to repeat and rework the expression of my ideas for those who fail to see the point.
I think you are too sensitive. Your reactions to others are sometimes just as brittle but you seem to single me out for special treatment.
You voluntarily put your material up here for comment by all. I have been courteous throughout but I do not feel that you have been.
Don’t forget that we are all on the same side here.
Bob,
One doesn’t need to postulate a transfer of warm water from another basin. Merely a discontinuity in the temperatures along the flow line of the thermohaline circulation or some other oceanic circulation.
But you don’t want to discuss it so that’s that.
Bob,
Thanks for this post – it was very informative. Over at the TAV blog, I saw the oceanic oscillations as being similar to a similar inductive-capactive tank as expressed by Ruhroh. I look forward to your introductory material on the various oceanic oscillations.
Stephen Wilde (06:30:38): You wrote, “I am not trying to discredit you.”
Yet in an earlier comment on this thread you wrote, “…but some of the examples strain credibility.” In another comment you wrote, “There seems to be a logical inconsistency there.” And in another one, you wrote, “The most likely implication of the unlikeliness of that proposition…” And you continued, speculating, “Thus possibly (I’m not sure on this yet) Bob could have the causation reversed.”
And now you claim, “I have been courteous throughout but I do not feel that you have been,” and, “I think you are too sensitive.”
Here at WUWT and at other science blogs, if a courteous blogger with research-based knowledge of the subject matter disagrees with a post or part of it, they explain their disagreement and document the basis of their disagreement with data, most times in the form of graphs, and/or they document it with links to papers or blog posts. You, however, speculate, and through that speculation, you cast doubt on the work of others. On this thread and others, you present objections that have no foundation, no basis in fact. You often shift timescales outside of the one being presented (well beyond the instrument record) and present conjecture. Many times you write in such general terms that when you are confronted with instrument records that contradict your speculations, you shift to paleoclimatological timeframes, and then when confronted with paleoclimatological reconstruction data that refute your conjecture, you rely on the generality of your writings to claim it wasn’t what you meant.
In my (04:03:11) reply to you today, I responded to one of your earlier speculative objections with graphs that indicated there is no evidence that warm water transferred from another ocean basin to the tropical Pacific to cause the 1995/96 rise there. I showed that the height of the water column of the tropical Pacific reflected the same rise as the 1995/96 OHC, countering your inference that a pocket of warm water rose up from below the 700 meter depth in the tropical Pacific. As is typical, in your most recent reply, you offered conjecture with respect to the 1995/96 rise in tropical Pacific OHC when you wrote, “One doesn’t need to postulate a transfer of warm water from another basin. Merely a discontinuity in the temperatures along the flow line of the thermohaline circulation or some other oceanic circulation.”
Once again, I will ask you to document your unspecific conjecture (with data or with a reference that confirms your statement) that “a discontinuity in the temperatures along the flow line of the thermohaline circulation or some other oceanic circulation” is the cause of the 1995/96 rise in tropical Pacific OHC. If you attempt to use data, I will suggest that you center your research on the Pacific Warm Pool, because that’s where the 1995/96 rise was located, as one would expect and as documented in the reference linked to the post. And if you elect to use coordinate-based data, you must also consider that the Pacific Warm Pool varies in geographic area in addition to temperature and depth. This could add some complexity to your studies.
Will you respond by documenting your conjecture about the 1995/96 rise in tropical Pacific OHC, Stephen?
There is nothing wrong with raising questions.
There is nothing wrong with conjecture based on the available data.
That is the essence of science.
None of us knows everything and all you are suggesting to me is that I go away and find out for myself without bothering you. Yet the data just isn’t there to answer such questions. If your dismissive assertions were an appropriate response then there would be no point in these blogs at all.
Anything that occurs to me will occur to others and we would all benefit from a clear polite response.
Actually I’m beginning to see why I irritate you so much.
My questions are exposing holes in your neat self-contained ENSO / PDO scenario every bit as large as the gaps which I readily acknowledge in my own endeavours and which you have so forcefully (and often rudely) brought to my attention.
You seem to be treating every chunk of warm water in each ocean as a discrete moveable item. You then go on to suggest that the ocean heat content profiles in each ocean are readily determinable on the basis of eyeballing some ocean heat content charts. The data used to produce those charts is far from perfect.
You then draw conclusions and produce lots more charts and diagrams as though you are describing some complete and incontrovertible truth.
The trouble is that you then cannot link any of that to the wider and longer term scenario in relation to which it only forms part and you don’t like me trying to do just that.
It’s not only me who has noticed that you cannot demonstrate what causes ENSO in the first place. You correctly mention air circulation and the Trade Winds and that’s fine, it’s obviously the proximate cause of ENSO events. But what initially causes those air circulation changes?
We cannot just say ENSO causes air circulation and Trade Wind changes which then cause ENSO in a never ending loop divorced from the rest of the Earth system
However you have said as much elsewhere :
“It is clear that significant El Nino events can and do cause upward step changes in Ocean Heat Content. This indicates that ENSO events do more than simply release heat from the tropical Pacific into the atmosphere. Apparently, El Nino events also cause changes in atmospheric circulation in ways that impact Ocean Heat Content”.
Essentially you are saying that ENSO via EL Nino and La Nina events can cause pretty much every climate change via it’s influence on the atmospheric circulation without considering other ways that global ocean heat content could either vary or move about and thereby affect the air circulation on a much more global basis than just via ENSO.
That’s why you have to stipulate that PDO is a mere statistical artifact or a consequence of ENSO. If PDO has any independent existence then your chain of causation falls into question. You cannot accept any suggestion that PDO is an independent phenomenon driven by other forces because that would affect your all powerful view of the ENSO mechanism. The same applies to the oscillations in all the other ocean basins.
I propose that something other than ENSO occurs first and that is likely to be a change in the net rate of energy transfer from all the oceans to air (globally averaged). The air circulations then shift positions and intensities, the Trade Winds alter and ENSO follows.
So like you I agree that the oceans are the key but you seem to have tied yourself to ENSO alone whereas in fact every ocean has a similar oscillation and they don’t all work together. Sometimes they offset one another and at other times they supplement one another and although it is the biggest I do not think ENSO has absolute control.
You also ignore any possibility of temperature discontinuities along the line of the thermohaline circulation which could go unnoticed by the currently inadequate ocean heat content figures but greatly affect the rates of energy release from oceans to air over time.
Note that I refer to RATES of energy transfer. I do not refer to absolute temperatures in a defined area. I think that all climate phenomena are a consequence of changing RATES of energy transfer over time in varying parts of the Earth system. Thus there are primarily internal system changes forcing climate responses, not primarily external such as the absolute value of solar power (except over much longer time scales).
Indeed the ENSO process itself may well be a negative feedback working against the forces (varying rates of energy transfer) that caused the air circulation changes in the first place. It might not be a cause at all in itself.
It is very important to resolve the causation issue and to give ENSO the correct weighting because that opens the door to fitting ENSO into the wider perspective especially the climate cycling from MWP to LIA to date. If your ENSO description cannot accommodate that longer term cycling then ENSO is being ruled by other forces and does not have the influence on the atmosphere that you attribute to it.
Conjecture and speculation from observation and recognising the limitations of the available data is critical for the progression of science.
There are many other contributors here who approach climate issues from a generalist point of view yet you have been mostly picking on me. Perhaps my comments are inconvenient for you. It is aggressive attention from you that has drawn me to look at your work in more detail and frankly despite all the wonderful decor that you produce at the heart of it there is no more a demonstrable truth than is provided by the efforts of the rest of us.
Stephen Wilde: I asked, “Will you respond by documenting your conjecture about the 1995/96 rise in tropical Pacific OHC, Stephen?”
And you did not.
My reference to the 95/96 rise in tropical OHC was an acceptance that I had missed something you said previously. I was conceding a point.
My main point was entirely separate i.e. that without additional information it was inherently implausible (i.e. not entirely credible) that 3 years of La Nina in the 70’s would energise two decades of strong El Ninos without supplementary assistance and I proposed that such assistance might arise from temperature discontinuities in the horizontal flow of the thermohaline circulation.
One of the problems I have with you is that you keep misreading things that I say and then you go off at an irrelevant tangent. I have the same type of problem with warmists.
Bob,
OK, I can see the confusion. I was initially talking about the 1970’s La Ninas energising the subsequent two decades but in fact you were talking about the 05/96 La Nina replacing what had been lost in the previous two decades.
However my basic point remains valid. Given that the ocean heat data are not particularly accurate I don’t see how you can jump to such a neat conclusion that La Ninas and El Ninos always and at all times integrate to provide the necessary energy swings to account for all climate variability.
It’s true that you can produce chart after chart expressing linkages but they are just part of the wider scenario and I think you need my perspective to get from ENSO to the longer term climate cycling from MWP to LIA and today.
As I said before:
“We cannot just say ENSO causes air circulation and Trade Wind changes which then cause ENSO in a never ending loop divorced from the rest of the Earth system.”
I have never wished to fall out with you but I do find your attitude to my attempts at understanding deeply frustrating. It really is not necessary to assume ill will on my part.
Perhaps you could now address my points in a way that would be enlightening for all ?
Whoops 95/96 La Nina is what I should have typed.
lgl, the Nasa eclipse web server is now functional:
http://eclipse.gsfc.nasa.gov/eclipse.html
I’ve accessed the map file. Can you explain for us the method by which you derive the curves from the sequence of maps?
Piers Corbyn has a humorous take on using El Nino as an “explanation”:
“The problem is El Nino does not cause weather it IS weather and all these clever-sounding so called causes of weather and climate the Met Office come up with (El Nino, La Nina, Arctic Oscillation, North Atlantic Oscillation etc etc) are description NOT CAUSE. They are like saying:
-There are a lot of people in Oxford street because it’s crowded.
– Crime waves cause crime
– Climate Change causes climate change.”
http://climaterealists.com/index.php?id=5090
–
Stephen, I would suggest that external factors influencing atmospheric pressure variations (& hence flow AND CLOUDS), which operate on more than one timescale, are largely responsible for what many choose to ascribe to “ocean cycles”. I recommend googling the works of Russian scientists Sidorenkov & Barkin (while also keeping an eye on whatever Piers Corbyn might eventually decide to share with us about the solar-disruption part of the picture).
Paul Vaughan (21:41:19)
Yes that is one of the options but generally I find it implausible because of the thermal inertia of water and the need to accommodate those larger MWP to LIA to date climate swings.
Also one would need to observe the air circulation systems moving latitudinally BEFORE the ocean sea surface temperatures change and I don’t think that happens does it ?
Still, with so many now looking into it the answer should become clearer soon.
Stephen Wilde, hopefully this is a final note to you from me on this thread.
Your continued conjectural comments and your misrepresentation of the content of my work expose your failure to understand what I have done for over a year and continue to do. Climate alarmists claim the rises in OHC, SST and TLT anomaly data are overwhelming proof of anthropogenic global warming. I have illustrated and document that there are multiyear aftereffects of ENSO events that cause the positive trends in SST and TLT anomalies outside of the tropical Pacific, and I have shown that the rise in global OHC, when broken down into logical ocean basin subsets, is dominated by natural variables. If I were to speculate about additional natural factors; such as THC/MOC, or some assumed millennial ocean cycle, or some third unknown factor that impacts ENSO and the PDO, or some initiator of ENSO events; that speculation would detract from my work, not add to it. It would afford others the opportunity to discredit my posts–something you seem hell bent to do. If and when you can provide data or references to document your claims, or if you were to point me to those data or references–data and references that would help illustrate and document my posts, (which are about the multiyear aftereffects of ENSO events on global SST and TLT anomalies, and about the discharge/recharge aspects of ENSO, and about the impacts of ENSO, NAO, NPI, AMO on OHC, not the PDO, not what initiates ENSO events, not millennial ocean cycles, etc.)–I would be happy to include it. Until then, your continued speculation about issues you believe are important detracts from the very obvious intent of my posts.
If THC/MOC, or some assumed millennial ocean cycle, or some third unknown factor that impacts ENSO and the PDO, or some initiator of ENSO events are so important to you, write a post for WUWT.
Paul Vaughan (21:16:44) :
The method I used is very simple. Using 2010-2013 as example, the eclipses in 2010 and 2013 are typical low latitude and those in 2011 typical high latitude. So I would give 2010 and 2013 a value of 1 and 2011 a 0 value. There will be a few like 2012 on mid-latitude which is hard to determine but it doesn’t matter whether you give it a 0 or a 1. On a long time span you will get the average periode of 3.6 years regardless.
Bob,
For what it’s worth I have always considered that your work as described in your post of (03:57:45) has been entirely successful.
I will seek elsewhere the information I need to take the further steps.
Thank you.
Stephen Wilde: You replied, “For what it’s worth I have always considered that your work as described in your post of (03:57:45) has been entirely successful.”
Yet this post that you disgree with so heartily is simply a rewording of my past posts “as described in” my “post of (03:57:45).” The only new aspect was the illustration of the shift in the Northern Hemipshere SST anomalies for the Mid-to-High Latitudes. So your last comment disagrees with your prior comments on this thread.
Stephen Wilde (00:59:57) “Also one would need to observe the air circulation systems moving latitudinally BEFORE the ocean sea surface temperatures change and I don’t think that happens does it ?”
In Barkin’s paradigm, the Earth is not a uniform, homogeneous sphere – i.e. things like topography have a role. Also, cause and effect aren’t likely to fall into nice, separate boxes when there is coupling.
…But there is enough complexity for us all to agree to play different roles in these discussions — disagreement is normal given the complexity – and therefore not a stressor. Thanks for your contributions, which come in a form which I’ve noticed many here appreciate.
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Bob, I appreciate your level of awareness of the different datasets – that is of great value to the community – thanks again for the notes.
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lgl, so basically 18.6 / 6 (i.e. the 6th harmonic of the lunar nodal cycle) is what you believe you’ve isolated (on average) from the eclipse maps?
Correction: 18 / 5 (i.e. the 5th harmonic of the Saros Cycle) – is that what you are thinking lgl?
Or perhaps the beat of 3 years with the LNC? And before I turn my attention to this more seriously, it will be helpful to know what caused you to even look into this – Corbyn’s notes? a journal article? Any notes you are willing to share will be appreciated – if I can avoid time spent reinventing the wheel, thanks for the notes.
Bob Tisdale (15:25:07)
That unfortunate misapprehension has been a source of discomfort for both of us.
Your work is clear and sound for the purpose of disposing of AGW but not for the purpose of a full climate description.
If one could extend your work in the way I have suggested then it would be strengthened not weakened but I accept your explanation that you did not want to introduce issues that would have given warmists sticks to beat you with.
Now that AGW is imploding perhaps you could reconsider ?
I hope we can discuss matters in the future without such a misapprehension in the background.
Believe me, I’ve had to put up with a lot worse elsewhere than you have had to put up with here.
Paul Vaughan (20:47:55) :
I was actually looking for traces of Basils 9 year cycle http://wattsupwiththat.com/2009/11/30/what-do-we-really-know-about-climate-change fig.1 so it was just a coincidence.
I don’t know why 3.6 years but since the Saros is linked to the synodic, anomalistic and draconic months I guess the 3.6 is also.
lgl, I worked it out:
http://www.sfu.ca/~plv/Eclipse_Sin_LNC-3a.png
It’s the beat of LNC with 3 terrestrial years.
I will likely have more to say about this in the days/weeks/months ahead since it reinforces what I’ve already demonstrated here:
http://www.sfu.ca/~plv/DRAFT_VaughanPL2009CO_TPM_SSD_LNC.htm
(Btw, that page needs a fairly serious round of updating.)
I’ll likely initially comment in tallbloke’s forum, which affords a less rushed pace and does not tolerate political obstruction. I hope you will join the discussions there. To find the forum, just click on tallbloke’s name above.
Best Regards,
Paul.
Paul Vaughan (13:41:24) :
Looking good but I’m afraid I still don’t understand why 3.6 years (or “beat of LNC with 3 terrestrial years”)
tallbloke’s seems like a good place for the really puzzling things in life.