Can El Nino Events Explain All of the Global Warming Since 1976? – Part 1
A guest post by Bob Tisdale
UPDATE 1 (January 12, 2009):
In my extremely brief description of an El Nino event, I wrote, “…and a subsurface oceanic temperature boundary layer called the thermocline pushes the warm subsurface water to the surface.” My oversimplification may be misleading, and while it does not undermine the intent of this post, a better explanation is available in the following video from NASA Scientific Visualization Studio video titled “Visualizing El Nino”: http://svs.gsfc.nasa.gov/vis/a000000/a000200/a000287/a000287.mpg
If I rewrite that sentence in the future, it would read something to the effect, “During El Nino events, natural changes in atmospheric and oceanic conditions cause the warm water that was ‘contained’ by the Pacific Warm Pool to shift east along the equator. The warm subsurface water rises to the surface.”
h/t Gary for noting the poor wording.
NOTE: For those who are new to the subjects of El Nino events and sea surface temperatures, I’ve tried to make the following discussion as non-technical as possible without overlooking too many aspects critical to the discussion. It includes detailed descriptions of many of the processes that take place before, during, and after El Nino events. The period after an El Nino event is often neglected, but it holds the oceanic responses that are the most significant over multiyear periods.
INTRODUCTION
Two things have always stood out for me in a graph of Global Sea Surface Temperature (SST). The first was the Dip and Rebound in the ERSST.v2 version of the Extended Reconstructed SST data from the 1800s to the 1940s. The link above discussed it in detail.
In Figure 1, I’ve boxed SST anomaly data for the period from 1854 to 1976 to indicate that, other than the dip and rebound and the temporary rise in the early 1940s caused by a multiyear El Nino, there really wasn’t a rise of any note in SST between the late 1800s and the period from the mid-1940s to mid-1970s. The ERSST.v2 data used in this post illustrates little to no change in SST anomalies from the one period (late 1800s) to the other (mid-1940s to mid-1970s).
http://i42.tinypic.com/2ibc87o.jpg
Figure 1
Second: After 1976, Global SST anomalies appear to rise in three steps. It’s very visible if monthly SST anomaly data has been smoothed with a 37-month filter, Figure 2, or if annual data has been smoothed with a 3-year filter. Many people try to correlate those steps with variations in TSI, because they seem to coincide with solar cycles. They don’t, so those trying to make the correlation fail in their efforts.
http://i41.tinypic.com/29omma1.jpg
Figure 2
Zooming in on the period from January 1976 to present, Figure 3, and changing the filtering from 37-months to 12-months do not eliminate the appearance of steps. Why did Global SST rise in steps after 1976?
http://i41.tinypic.com/71mbd3.jpg
Figure 3
Based on the title of this post, the rising step changes were caused by El Nino events, three in particular. The NINO3.4 SST anomalies from January 1976 to November 2008 are shown in Figure 4. Most people familiar with the recent El Nino-Southern Oscillation (ENSO) record could guess correctly that the 1997/98 El Nino event was one of the El Ninos that caused a step change. If the magnitude of El Ninos was the only factor, the second logical choice would be the 1982/83 El Nino, since it ranks a close second in terms of peak NINO3.4 SST anomaly. Yet that El Nino event did not create a rising step change in global SST anomalies, because another natural event had a greater impact on global climate.
http://i44.tinypic.com/s46yhe.jpg
Figure 4
A volcanic eruption. The El Chichon eruption of 1982 interrupted the normal heat distribution processes of the 1982/83 El Nino. Many persons understand and cite this on blogs. Few realize, though, that the 1991 eruption of Mount Pinatubo also interrupted a significant series of El Nino events. The Mount Pinatubo eruption didn’t occur at the same time as a singular El Nino event with monstrously high SST anomalies, but the string of El Ninos it influenced was significant in its length. “Full-fledged” El Nino events occurred in 1991/92 and 1994/95, with a minor El Nino occurring during 1993. At minimum, two of the early-to-mid 1990s El Ninos had their heat distribution processes altered.
REFERENCE ILLUSTRATIONS
Figure 5 is a comparative graph of East Indian-West Pacific SST anomalies, scaled NINO3.4 SST anomalies, and inverted Sato Index of Stratospheric Mean Optical Thickness data (used as a reference of volcanic eruption timing and intensity). The data in Figure 5 have been smoothed with a 12-month running-average filter. The step changes in the East Indian-West Pacific SST anomalies are quite obvious. The graphs included in the following discussions are edited versions of Figure 5. In the latter graphs, I have simply limited the years in view to the periods being discussed. The three periods (January 1976 to December 1981, January 1981 to December 1995, and January 1996 to November 2008) are also shown in Figure 5. The periods were divided in this way because, working backwards in time, the first period discussed (1996 to 2008) has been covered in an earlier post and is, therefore, easiest to explain, the second period (1981 to 1995) includes the two volcanic eruptions, and the third period (1976 to 1981) is what was left over. Note that the NINO3.4 and Sato Index data are provided to illustrate timing and timing only; they have not been scaled to suggest magnitude of cause and effect. I did not want to get into a debate about scaling.
http://i44.tinypic.com/10oe6uo.jpg
Figure 5
In Figure 6, I’ve blocked off the area of the East Indian and West Pacific Oceans illustrated by the black curve in Figure 5 and in illustrations that follow. The coordinates are 60S to 65N, 80E to 180. It represents a significant portion of the world oceans, in the range of 25 to 30% of global sea surface from 60S to 65N.
http://i39.tinypic.com/5n55as.jpg
Figure 6
Figure 7 is a comparative graph of the NINO3.4 SST anomalies, inverted Sato Index, and the SST anomalies for the oceans segments not included in the East Indian-West Pacific SST anomaly dataset above. These include the East Pacific, the Atlantic, and the West Indian Oceans contained by the coordinates 60S-65N, 180-80E. The East Pacific-Atlantic-West Indian Ocean data (red curve) is overlaid onto the East Indian-West Pacific data (the black curve in Figure 5) during the discussions that follow to show the interactions between datasets.
http://i44.tinypic.com/2ljgxon.jpg
Figure 7
A final preliminary note: The filtering is used to reduce the visual impact of the noise within the datasets. It also affects (smoothes) the abruptness of the change in the Sato Index data when the volcanoes erupted. It has a minor visual impact, but it is something to consider when viewing the graphs that include the volcanic eruptions (Part 2). The impacts of the smoothing are shown in Figure 8.
http://i39.tinypic.com/be5x6a.jpg
Figure 8
A VIDEO
I illustrated the cause of the step change AFTER the 1997/98 El Nino in a video posted on the thread titled The Lingering Effects of the 1997/98 El Nino. The YouTube link is here: http://www.youtube.com/watch?v=4uv4Xc4D0Dk
Take five minutes and watch the video. It will help to illustrate the phenomena taking place and the causes.
Note: In the graphs for the video, I used the Optimally Interpolated SST anomaly data (OI.v2). The monthly time-series data for it starts in November 1981, and since I wanted to cover the period starting in 1976 in this post, I had to switch datasets. The SST anomaly data used in the following discussion is from the Extended Reconstructed Sea Surface Temperature, Version 2 (ERSST.v2), available from the National Climatic Data Center (NCDC). It runs from January 1854 to present.
THE STEP CHANGE FROM 1996 TO PRESENT – A RECAP AND EXPANSION OF DISCUSSION
The SST anomalies for the West Indian-East Pacific Oceans from January 1996 to November 2008 are shown in Figure 9, along with scaled NINO3.4 SST anomalies and the final few years of the inverted Sato Index data. The Sato Index ends in 1999, but because there has not been an explosive volcanic eruption capable of lowering global temperatures significantly since 1991, its end in 1999 has no affect on the discussion.
Note: You may wish to click on the TinyPic link (While holding the “Control” key) to open Figure 9 in a separate window. That would eliminate the need to scroll back and forth. This discussion goes on for a full page of single-spaced text in MSWord form.
http://i43.tinypic.com/zxr6vc.jpg
Figure 9
The Pacific Warm Pool, also known as the Indo-Pacific Warm Pool, is an area in the western equatorial Pacific and eastern Indian Ocean where huge volumes of warm water collect due to a number of natural processes (normally attributed to ocean currents and trade winds). The Pacific Warm Pool is visible in SST data and in subsurface ocean temperature data; the warm pool reaches down to depths of 300 meters. Figure 10 illustrates its location. Over decadal periods of time, it expands and contracts in area and increases and decreases in volume. 
http://i42.tinypic.com/2hdqydy.jpg
Figure 10
During El Nino events, natural changes in atmospheric conditions cause the warm water that was “contained” by the Pacific Warm Pool to shift east along the equator, and a subsurface oceanic temperature boundary layer called the thermocline pushes the warm subsurface water to the surface. The high SST anomalies in the eastern equatorial Pacific are known as an El Nino. It is a natural process that occurs at irregular intervals and magnitudes. The eastern equatorial Pacific SST anomaly data is divided into areas for monitoring purposes. Refer to Figure 11. These areas are known as NINO1, 2, 3 and 4. Global temperature responses to El Nino events correlate best with the SST anomalies of an area that overlaps NINO3&4 areas. That area is called NINO3.4. That’s the data set used in the following discussions.
http://i44.tinypic.com/97qt08.jpg
Figure 11
Back to the discussion of Figure 9: The purple curve in Figure 9 shows the SST anomalies for the NINO3.4 area [5S-5N, 170W-120W] in the eastern Pacific. The data has been reduced in scale by a factor of 0.2 so that it doesn’t overwhelm the graph. During the 1997/98 El Nino event, NINO3.4 SST anomalies rose to their highest levels during the 20th century. Its impact is visible in the long-term and short-term Global SST anomaly data shown in Figures 2 and 3. It affected global and regional temperature and precipitation patterns in the short term afterwards.
That’s usually about the end of a discussion of the 1997/98 El Nino. The video showed, however, that other processes continue long after an El Nino event. Much of the heat that rises to the surface during the El Nino is then transported west by the equatorial ocean currents, recharging the Pacific Warm Pool for the next El Nino and heating the surface of the East Indian-West Pacific Oceans. It’s important to keep in mind that before the El Nino most of the warm water was below the surface, contained by the Pacific Warm Pool. Since it’s below the surface to depths of 300 meters, it is not a part of the calculation of global SST, or global temperature, for that matter. Then, after the El Nino, much of it is on the surface and included in the SST data. The resulting rise in the SST anomalies of the East Indian-West Pacific Oceans (the black curve in Figure 9) lags the change in NINO3.4 SST anomaly by a few months. As shown, East Indian-West Pacific Ocean SST anomalies reached their peak in 1998, but by that time, NINO3.4 SST anomalies had already dropped back to “normal” levels. Then the NINO3.4 SST anomalies dropped further, into the subsequent La Nina (Negative) levels, but the East Indian-West Pacific Ocean SST anomalies only dropped a portion of the amount they had risen, about one-half of it. And before the East Indian-West Pacific SST anomalies can slowly decrease fully to the levels they were at before the 1997/98 El Nino, NINO3.4 SST anomalies increase in 2000 and cause the East Indian-West Pacific SST anomalies to rise again. That’s the step change.
In summary, a large volume of warm water that was once below the surface of the Pacific Warm Pool was raised to the surface by the El Nino and distributed across the surface of the East Indian and West Pacific Oceans, causing SST anomalies to rise in that region. East Indian-West Pacific Ocean SST anomalies began to drop but had not had enough time to return to “normal” before the start of the next El Nino event, which swept them upwards again.
They are slowly returning to the levels they were at before the 1997/98 El Nino, but because they were “pushed” higher again and again by the El Nino events of 2002/03, 2004/05, and 2006/07, the return has taken more than a decade.
In Figure 12, I’ve added the SST anomalies for the East Pacific, Atlantic, and West Indian Oceans to the comparative graph. (It’s another graph you may want to open in a separate window.) The East Pacific-Atlantic-West Indian Ocean SST anomalies mimic the rise and fall of the NINO3.4 SST anomalies during the 1997/98 El Nino—to a point. Note how, during the La Nina that followed it, the NINO3.4 SST anomalies have dropped well below the levels they had been at before the start of the 1997/98 El Nino (highlighted with the blue line and arrows), yet the East Pacific-Atlantic-West Indian Ocean SST anomalies don’t follow the NINO3.4 SST anomalies below the level they had been at before the 1997/98 El Nino to any great extent; that’s another (but smaller) cause of the step change in Global SST anomalies after the 1997/98 El Nino. Then the East Pacific-Atlantic-West Indian Ocean SST anomalies follow the rise in NINO3.4 SST anomalies from 2000 to late 2002, the peak of the next El Nino. And, from 2003 to present, the SST anomalies for both of the major portions of the global oceans (red and black curves) “normalized” to levels near to one another, modulating back and forth as each area, at different time lags, responds to variations in NINO3.4 SST anomalies. These include the additional El Nino events of 2004/05 and 2006/07, and finally a substantial La Nina in 2007/08. Because of that La Nina, the East Pacific-Atlantic-West Indian Ocean SST anomalies (red curve) have dropped down close to the levels they had been at prior to the 1997/98 El Nino, but it has taken more than 10 years.
http://i40.tinypic.com/21o6a0z.jpg
Figure 12
In Figure 13, the Global SST anomaly curve from January 1976 to November 2008 (same graph as Figure 3) has been annotated to indicate the causes of the step change. As illustrated and discussed in the preceding, the temperature rise resulted from the significant step response of the East Indian-West Pacific SST anomalies to the 1997/98 El Nino event–that was compounded by a similar response (but of lesser magnitude) to the 2002/03 El Nino—that was then “maintained” by the El Nino events of 2004/05 and 2006/07.
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Figure 13
CLOSING TO PART 1
That’s enough for one post. In the second part, I’ll cover the two earlier periods. For a preview, simply scroll back up to Figure 5 and note the step changes during those two periods and the effects of the two volcanic eruptions. (Remember that the Sato Index data is only there to illustrate the timing of the volcanic eruptions.) I’ll also add another phenomenon that confirms the step changes caused by the El Nino events are drivers of global temperature anomalies.
SOURCES
Smith and Reynolds Extended Reconstructed SST Sea Surface Temperature Data (ERSST.v2) and the Optimally Interpolated Sea Surface Temperature Data (OI.v2) are available through the NOAA National Operational Model Archive & Distribution System (NOMADS).
http://nomads.ncdc.noaa.gov/#climatencdc
The Sato Index Data is available from GISS at:
http://data.giss.nasa.gov/modelforce/strataer/
Specifically:
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This is very much in line with climatologist Dr. Spencer’s work on PDO.
But remember this: AGW has never been about science or cliamte. AGW is a social movement that has used scientific sounding claims, and scientists, to achieve a social goal. Its social goal is power.
It seeks the power to impose change on the world.
I think this misrepresents the physics of the situation. The thermocline is merely the steep gradient part of the water temperature curve. It can’t “push” anything. What actually happens in the Eastern Equatorial Pacific is that diminished trade winds greatly reduce the upwelling of deep cold water off the Peruvian coast and allow the surface waters (down to a couple of hundred meters) to heat up from local insolation. It may look like the warm water is advancing from the west, but it’s really the heating in the east “catching up” to the heating in the west.
Please make sure and vote. I had an astonishingly unpleasant e-mail exchange this weekend with pzmyers, the blogger at Pharyngula this weekend. Gavin at Real Climate comes across as a gentleman by comparison.
I have no idea how Pharyngula could be only 2,000 votes behind, but it is critical that everyone gets out and votes during the next two days.
http://2008.weblogawards.org/polls/best-science-blog/
Total lame-man here…
but the in addition to PDO being in warm phase at the time, 1998, the Atlantic Multidecadal osciaalion had also switched to warm phase. And there was a real hot spike in 1998:
Graph:
http://upload.wikimedia.org/wikipedia/commons/thumb/1/1b/Amo_timeseries_1856-present.svg/672px-Amo_timeseries_1856-present.svg.png
Data:
1998>> 0.172 0.333 0.363 0.337 0.418 0.530 0.534 0.562 0.462 0.432 0.367 0.322
http://www.cdc.noaa.gov/Correlation/amon.us.long.data
Thanks bob. You must be right about not mistaking weather for trends. We’ll see in a few weeks.
When is NASA’s latest data on the warmest Dec in 50 years coming out? It’s always a cooker with NASA.
RE: Tony Heller (05:55:50) :
I wouldn’t worry Tony – pzmyers is an extraordinarily angry and bitter person when he’s on any subject other than pure science, so it’s not personal.
As for the gap between WUWT and Pharyngula, that’s down to tactical voting. Happens all the time :).
interesting…there seems to be some conclusion as to the discrepancy between the UAH and RSS tropospheric measurements…
Should RSS correct their lower troposphere satellite data?
http://www.warwickhughes.com/blog/?p=196#more-196
Beautiful work Bob, I can only imagine how much time went into it!
When I first began studying the climate in the early ’80s, no one had any idea the Equatorial Pacific Warm Pool even existed. As you probably know from your research, the EPWP wasn’t “discovered” until the late 1990s. But in fact, it has now been traced back until at least the 1500s and possibly long before that (see http://www.epwp.com).
After it’s “discovery,” every major Nation in the world aimed their research vessels toward the area and to date, it is estimated they have collectively spent over 100 Billion US dollars to investige the “anomoly,” many with a vision of controlling the world’s weather. This especially became apparent after Atmospheric Scientist Vikram Mehta (I believe) referred the EPWP as “The World’s Thermostat.”
Although I haven’t anything but gut instinct to support my theory, I believe Mehta was correct: it is the world’s T-Stat. However I also believe that the sun is the controlling influence over which personality the EPWP assumes:ElNino, LaNina, or ElNino Neutral.
Although we’ve been in uncharted territory since the “discovery of the “pool,” we are on the threshold of some of mankind’s greatest discoveries: how our climate systems interact (teleconnect) with each other and how the sun does or does not play a central, if not a governing role in earth’s climate systems!
Thanks for all your hard work and devotion. It’ll take continued efforts like yours to unmask the simplistic pseudo scientists and their socialist, money grubbing agendas.
Jack Koenig, Editor
The Mysterious Climate Project
http://www.climateclinic.com
the latest sunspot is almost gone….looks like we’re heading for another spotless stretch.
http://sohowww.nascom.nasa.gov/data/realtime/mdi_igr/1024/latest.html
Stephen Wilde, spot on.
THE HOT WATER BOTTLE EFFECT,
The sun spot numbers of the last three cycles are higher than for the last 11,400 years, there does not need to be rising irradiance to achieve a rising temperature, just a high steady heat source and a heat sink, seems obvious to me, it`s the sun.
To much science not enough common sense.
Thank you for a yeoman’s effort retrieving ‘the rest of the story’.
Many thanks, Bob Tisdale, for this synthesis. As still a relative novice but with a strong background in scientific thinking, I can at least understand it, even though I have no specialized background from which to criticize/confirm it.
As one of my pet peeves concerning the AGW “science” is the false idea that prior Peer Review results in the Given Truth, and that only prior Review makes an analysis worth considering, I wonder if those adhering to AGW “science” will deign to review your work here, or will simply dismiss it as not worth considering – smack in the face of their opportunity to do their own Peer Review of it right now and in public.
Thanks to all who complimented.
Tallbloke, you wrote, “Bob, Excellent piece. Look forward to part 2. Will we get some quantification of the heat energy left in the pacific warm pool at various stages of the global warming story?”
I haven’t yet seen a study that quantifies PWP heat content over decadal periods, or yearly for that matter. I’ve run across the Indo-Pacific Warm Pool Index (IPWPI):
http://bobtisdale.blogspot.com/2008/12/indo-pacific-warm-pool-index.html
The Tropical Atmosphere Ocean (TAO) Project Office of NOAA Pacific has Equatorial Pacific Warm Water Volume data:
http://bobtisdale.blogspot.com/2008/11/equatorial-pacific-warm-water-volume.html
And the CDC has what they call the Equatorial Upper-Ocean Heat Content Anomaly data, which they clarify as “Equatorial Heat Content (average temperature in the upper 300 meters, deg C)”.
http://bobtisdale.blogspot.com/2008/11/average-subsurface-temperature-of.html
There’s also a lot of work on the PWP by Mehta:
http://www.decvar.org/documents/hawaii_workshop_2007/agenda/Session_3/3m_decvar_2may07.ppt?PHPSESSID=995d2a85e37d90b501876a0fb8ab6684
http://www.decvar.org/documents/airlie/Conference/Session_11/11.1_Mehta.ppt?PHPSESSID=796b2224c80f4f1c1b721814eab877c6
Paul Shanahan, you wrote, “I have a random theory to throw in here, but not sure how to explain it…”
Paul, you did a good job of explaining, but it sounds like a reversal of the AGW water vapor positive feedback theory, does it not?
John W., you wrote, “Thanks for the great article. A question if you have the time. Wouldn’t El Nino/La Nina events be result of TSI at the tropics? Presumably after some period (years) of warming/cooling?”
My comment to Dermot Carroll above came after yours. It read, People have been looking for a solar/ENSO connection for decades. No luck so far. There is an underlying trend in NINO3.4 data that seems to correlate with Southern Ocean SST anomalies, though.
otowi, you wrote, “So what causes El Ninos?”
Bill Kessler of NOAA’s Pacific Marine Environmental Laboratory has a great page of “Occassionally asked questions” about El Nino events. It’ll answer yours.
http://faculty.washington.edu/kessler/occasionally-asked-questions.html
Alex: You wrote, “I notice in Flanagan’s link that the Ocean temperatures in the Sea of Okhotsk are negative and yet ice formation is far below normal in that area currently… could volcanic activity be the cause? or perhaps winds?”
In my response to Flanagan, I noted that I don’t really pay attention to weekly snapshots of SST, so I can’t answer your question either. My problem with the weekly static images is I try to figure what’s causing what. Are they weather-related phenomenon, etc? Just what you’re doing. And that keeps me from looking at long-term variability.
I did provide him links to pages that I do keep track of:
http://www.cdc.noaa.gov/map/clim/sst_olr/sst_anim.shtml
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/wkxzteq.shtml
Pearland Aggie, you wrote, “Bob, great work. I’m betting we will be seeing answers to Tucker’s and others’ questions in Parts 2 and 3!”
Part 2 covers the periods from January 1981 to December 1995 and from January 1976 to December 1981, with a couple of additional notes thrown in at the end. Part 3 is still only one first-click spreadsheet. As noted above, I started on Part 3, where I looked at the years from 1935 to 1977, but ran into a snag with the “discontinuity” at 1945. Then, when I tried the raw COADS data for the period, an earlier adjustment gave me another thought and sidetracked me for an hour. I’ll try to get back to that and finish it within the next two days.
Hunter, you wrote, “This is very much in line with climatologist Dr. Spencer’s work on PDO.”
If the PDO is an aftereffect of ENSO events, as some propose, then, yes, we’re both discussing aftereffects of ENSO events. Other than that, I don’t see the similarities.
Gary, you wrote, “I think this misrepresents the physics of the situation. The thermocline is merely the steep gradient part of the water temperature curve. It can’t ‘push’ anything. What actually happens…”
Your description that follows that varies from NASA’s. Please refer to the NASA Scientific Visualization Studio video titled “Visualizing El Nino”.
http://svs.gsfc.nasa.gov/vis/a000000/a000200/a000287/a000287.mpg
For brevity sake I used “push” instead of “squeeze eastward where density differences causes the warm water to rise to the surface.”
Regardless of how we explain it, the step changes result from a simple process: An El Nino event transfers subsurface water from the Pacific Warm Pool (Warm water that’s up to 300 meters below the surface of the PWP is not included in the instrument temperature record) to the East Equatorial Pacific where it rises (The El Nino), then returns much of it to the surface of the East Indian and West Pacific Oceans, not just the Pacific Warm Pool (where the warm water is now included in the instrument temperature record).
Werner Weber: Thanks for the links and the emails.
Bob Tisdale,
Thank you for this detailed work. Where is the data for cloud cover?
It would seem that oceans can only store heat according to the amount of sunlight reaching them. Cloud dynamics are not well understood as IPCC AR4 acknowledges, and myriads of research papers support. Even if the sun were a constant heat source not unlike an incandescent light bulb, by whatever mechanism causing it, cloud cover changes would be an obvious mitigating factor in regulating SWR, hence ocean warming, and ultimately “global” warming.
I’ve inquired on multiple occasions in various blogs how increasing CO2 levels could account for the rise in OHC from 1993-2003 (Hansen et al 2005). Alas it has gone unanswered. Further, OHC stopped increasing in 2003, dropped, and has not moved upward since. This cannot be brushed off as mere “noise”. Where is the missing heat?
If after these ENSO events (particulary El Nino) the oceans do not accumulate more and more heat as was the case for the last several decades (save volcano eruptions), how can SST do anything but trend downward? El Nino periods will be less pronounced and La Nina more dominant. It all boils down to OHC in my view.
NOAA’s 3 mo forecast for Dec/Jan/Feb thus far is turning out to be a total flop. Met O is no different. These reporting agencies have placed all their eggs in the CO2-drives-temperature basket when the reality is something else is going on they cannot bring themselves about to acknowledge.
ENSO may not be linked to solar activity, but what heat source can warm the oceans other than the sun? Water in liquid form stores 1000x more heat than water vapor, and land does not to any insignificant degree. As water stores heat, it also emits it efficiently,
Is the heat released by oceans being replenished? If not, global warming is over.
otowi (05:02:43) : and others with a similar query including our knowledgeable and engaging Kim.
So what causes El Ninos?
First, congratulations to Bob on a great bit of detective work. I want to go through it carefully but I know already that climate change as we have seen it over the last century is written in Southern Oscillation typescript. I agree with him at the outset. Harry Van Loon has pointed out that La Nina is a solar maximum condition. Ponder the paradox. Solar Maximum is cool. How does Svensmark theory stand up to that observation?
Conventional climate science (and Leif Svalgaard) is in denial that solar radiation directly influences atmospheric dynamics within the troposphere. But temperature change has been observed at the tropopause (100hPa) on solar rotation time scales and when you start looking, the evidence is not hard to find. Strange as it may seem, the annual maximum air temperature in the southern troposphere at 30°S is seen at elevations above 300hPa in August when surface temperatures are at a minimum. This is due to seasonal cloud loss associated with regular atmospheric heating at this time (land mass distribution between the hemispheres), a seasonal increase in outgoing long wave radiation and the excitation of ozone. The increase in temperature in the upper troposphere in mid winter weakens surface atmospheric pressure, a seasonal manifestation of atmospheric dynamics driving the El Nino Southern Oscillation phenomenon on multi-year time scales.
Here is the explanation in brief:
1. El Ninos and La Ninas are the Pacific manifestation of a global increase or a decrease in sea surface temperature in the tropics.
2. Tropical sea surface temperature (20°north latitude to 20°south latitude around the globe) responds to variations in sea surface pressure in the south east Pacific at latitude 30°-40°south and 100°-120°west. Sea surface temperature rises as surface atmospheric pressure falls. Using annual data there is on most occasions a lag of six to 12 months. Surface pressure in 2008 was less than in 2007 when it reached the highest levels since 1948. It seems a reversal of the current La Nina state is likely in 2009 and possibly before March 2009. Some warming is currently apparent east of South America and the occurrence of warming in localized areas between 30°-40° of latitude is a notable feature of the map referred to by Flanagan above. The developing situation off South America is covered at http://www.met.igp.gob.pe/cpntc/sst/ANOMALIAS/archivo.html If you download the images for the 1997 -98 El Nino event you will see that it first manifested in March-May gathering force over northern hemisphere summer. That global warming event marked the start of solar cycle 23.
3. Sea surface pressure at latitude 30°-40°south and 100°-120°west responds to change in temperature in the upper troposphere due to the excitation of ozone by short wave solar radiation and long wave radiation from the Earth producing a strong increase in air temperature wherever ozone is present.
4. At 30°-40°south and 100°-120°west the upper atmosphere is unusually rich in ozone due to strong downdraft from the upper troposphere/lower stratosphere at that location. This is reflected in relatively cold 200hPa temperature. The air temperature between 500hPa and 1000hPa reacts to change in radiation with amplitude of change increasing with elevation. If upper troposphere temperature rises the upper air tends to ascend (its less dense) rather than descend, and surface pressure falls.
5. When surface pressure falls at 30°-40°south and 100°-120°west the easterlies that blow across the Pacific weaken, the classic manifestation of El Nino.
6. But all of the above is actually a sidelight, a symptom. Here is the real kicker. The rise in upper troposphere temperature in an El Nino is global but varies in intensity due to local ozone content. To the extent that temperature rises in the upper troposphere relative humidity falls and cirrus cloud evaporates. This enables more solar radiation to reach the surface of the Earth accounting for the increase in sea surface temperature. The most energetic response is seen in the Pacific but we should not fall into the trap of thinking that the cause of this phenomenon lies within the Pacific or even worse, within five degrees of the equator in the Pacific, where the ENSO monitoring effort is concentrated. The links between 200hPa temperature, cirrus cloud cover and increased radiation at the surface has been observed in South East Asia where the warm pool is located and where sea surface temperatures continue to increase during El Nino events.
7. One should never lose sight of the fact that winter temperature pole-wards of 35° of latitude is determined by stored energy in the oceans and the strength of the downdraft over the very cold zones like Greenland, Siberia and Antarctica. Summer temperature at mid to high latitudes depends upon the extent of cloud loss in turn dependent upon the humidity of the atmosphere in turn dependent upon the energy driving evaporation in the tropics. Our weather and climate depends upon dynamics in the tropics. The PDO is just a reflection of that. As Bob Tisdale firmly points out: “The PDO is dependent upon ENSO on all timescales.”
Many details of this explanation are laid out in various posts at http://climatechange1.wordpress.com
See in particular the articles with these titles:
The ENSO Driver
The Southern Oscillation and the Sun (1)
The Southern Oscillation and the Sun (2)
There is more to come, especially in relation to long term changes in specific and relative humidity at different levels in the atmosphere, a topic I hope to attack soon.
Conventional climate Science and the bastions of its practice want to maintain the notion that the cause of the Southern Oscillation is unknown. When it is acknowledged, and its ramifications and permutations explored, AGW theory will evaporate. Logic says that the Southern Oscillation has been with us since the continents assumed their current position. If the continents stay where they are the thing that influences upper troposphere temperatures to swing away from a simple annual cycle is the strength of that part of solar radiation that excites ozone. That will depend in turn on how the radiation is filtered through the atmospheric layers above the troposphere…….layers that contain just 20% of the mass of the atmosphere. Speculatively, the solar wind and the strength of the Earths own magnetic field is involved in determining the issue. We are well aware that ozone is due to the interaction of the suns radiation with the atmosphere. We need to monitor its vertical, seasonal and inter-annual changes more carefully and notice when temperatures peak at the different levels of the tenuous upper atmosphere. Ozone monitoring will tell us a great deal about the sun/earth system.
As far as I can see, El Nino can explain some local lows and hight in the temperatures during the months following on an El Nino event.
As far as I am aware this is a wether-problem and not a climate problem.
In my opinion the article fails completely to explain the underlaying trend of increasing temperatures.
G’day Bob.
I haven’t had time to digest your full post yet but I would like to add something. UAH data is out. I was playing with the numbers WRG to RSS MSU and noticed that nearly all the warming we have seen since !979 has happened in the Northern Hemisphere. The vast majority of it happened since the 1998 El Nino.
I’m wondering if what we have seen over the last eleven years is the pushing of the warm water into the slightly land locked waters to the north. In other words It is all one event. What effect this would have on the NAO or indeed what drives what is open for speculation.
All numbers are the averaged above or below the relevant data sets anomaly for the entire 31 years.
RSS MSU NH 0.14
UAH NH 0.0981
RSS MSU SH 0.0392
UAH SH 0.0329
Jack Koenig:
If we are now (at last) in the realms of looking for the real world mechanisms I’ve had a recent stab at it here:
http://co2sceptics.com/news.php?id=2499
Old hands can ignore the journalistic first half and just focus on the mechanism described in the second half.
Gary: “and allow the surface waters (down to a couple of hundred meters) to heat up from local insolation”
Nowadays local insolation (i am writing from Lima, Peru, SA) is low because of a big and low cloud cover, this, in turn, apparently caused by cold pacific waters.
Alex (05:04:16) :
“I notice in Flanagan’s link that the Ocean temperatures in the Sea of Okhotsk are negative and yet ice formation is far below normal in that area currently… could volcanic activity be the cause? or perhaps winds?”
Alex,
If volcanic activity would warm the water the temps would not be negative!
Therefore it must be the wind or a flaw in the presented data.
Willem de Rode (08:27:05) :
which “increasing temperatures” would you be referring to?
http://www.drroyspencer.com/latest-global-temperatures/
looks like oscillation to me, not a persistent increasing trend…
Stephen Wilde (08:32:44) wrote:
“If we are now (at last) in the realms of looking for the real world mechanisms I’ve had a recent stab at it here:”
Thanks Stephen, I’ve been reading some of your other work (The Hot Water…) and will go through this tonight!
Jack
Bob Tisdale (08:03:39) :
Paul, you did a good job of explaining, but it sounds like a reversal of the AGW water vapor positive feedback theory, does it not?
Thanks for your thought. I agree to a degree, but there’s nothing to say that reverse the situation and the cause/effects also reverse. I’d prefer to think of it as cyclical as aposed to a pure positive or negative feedback theory.