Guest post by Bob Tisdale
OVERVIEW
This post compares satellite-based Sea Surface Temperature (SST) anomalies to the hindcasts and projections of the multi-model mean of CMIP3 models. CMIP3 is the archive the IPCC used as the source of their models for AR4. The period being discussed runs from November 1981 to November 2011. This covers most of the recent warming period that began in the mid-1970s.
There are two modes of natural climate variability discussed in this post: the El Niño-Southern Oscillation (ENSO) and the Atlantic Multidecadal Oscillation (AMO). For those new to ENSO, refer to An Introduction To ENSO, AMO, and PDO – Part 1. And for those new to the AMO, refer to An Introduction To ENSO, AMO, and PDO — Part 2.
This post also illustrates the multiyear aftereffects of the 1986/87/88 and 1997/98 El Niño events on the Sea Surface Temperature anomalies of the Atlantic, Indian, and West Pacific Oceans. Those oceans cover approximately 67% of the surface area of the global oceans. I have presented the processes that cause the multiyear aftereffects of those ENSO events in numerous posts over the past few years, so they will not be discussed in detail in this post. For those interested in learning about those processes, I discussed them and illustrated them with time-series graphs and with animated maps of sea surface temperature anomalies and other variables, most recently, in a two-part series: ENSO Indices Do Not Represent The Process Of ENSO Or Its Impact On Global Temperature and Supplement To “ENSO Indices Do Not Represent The Process Of ENSO Or Its Impact On Global Temperature”.
NOTE: The data in this post have been adjusted for the effects of volcanic aerosols.
INTRODUCTION
In the recent series of posts that compare the IPCC hindcasts for 20th Century surface temperatures to observed surface temperatures (see here, here, here, and here), the only time period when models consistently agreed with observations was the late warming period, from 1976 to 2000. But even that is misleading, because it gives the incorrect impression that anthropogenic forcings such as Carbon Dioxide were responsible for the rise in surface temperatures. Illustrating the error in that assumption is relatively easy when Sea Surface Temperature anomaly data is adjusted for the impacts of major volcanic eruptions and when the global data is divided into two subsets: the East Pacific (coordinates of 90S-90N, 180-80W) and the Rest-Of-The-World (90S-90N, 80W-180). Refer to the map in Figure 1 for an illustration of those areas. And Figure 2 is a comparison of the Sea Surface Temperature anomalies for those two subsets.
Figure 1
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Figure 2
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DATA
The Sea Surface Temperature anomaly data used in this post is Reynolds OI.v2. It combines bias-corrected satellite observations for more complete coverage and in situ observations from buoys and ships. The Reynolds OI.v2 Sea Surface Temperature data covers the period of November 1981 to November 2011, or 30 years. The Reynolds OI.v2 data is available through the NOAA NOMADS website here. There is another reason why the Reynolds OI.v2 data is used in this post: Smith and Reynolds (2004) Improved Extended Reconstruction of SST (1854-1997)stated about the Reynolds OI.v2 data:
“Although the NOAA OI analysis contains some noise due to its use of different data types and bias corrections for satellite data, it is dominated by satellite data and gives a good estimate of the truth.”
The truth is a good thing.
We’ll also be using the multi-model mean of the Sea Surface Temperature data that was produced by the climate models in the CMIP3 archive, where CMIP3 stands for Phase 3 of the Coupled Model Intercomparison Project. CMIP3 is the archive the IPCC used as the source of climate model data for its 4th Assessment Report. The CMIP3 Sea Surface Temperature data, identified as TOS, is available through the Royal Netherlands Meteorological Institute (KNMI) Climate Explorer website, specifically at their Monthly CMIP3+ scenario runswebpage. We have discussed in the recent posts that the multi-model mean represents the natural and anthropogenic forced component of the IPCC’s climate model outputs. And during the period we’ll be evaluating, it is the IPCC’s contention that anthropogenic forcings are the cause of the rise in surface temperatures.
The last discussion about the data is how the adjustments were made to account for the volcanic aerosols. The observational and model mean data are adjusted for the effects of volcanic aerosols, which would have major impacts on how the data was perceived during and for a few years after the explosive volcanic eruptions of El Chichon (1982) and Mount Pinatubo (1991). To determine the scaling factor for the volcanic aerosol proxy, I used a linear regression software tool (Analyse-it for Excel) with global Sea Surface Temperature anomalies as the dependent variable and GISS Stratospheric Aerosol Optical Thickness data (Source ) as the independent variable. The scaling factor determined was 1.431. This equals a global SST anomaly impact of approximately 0.2 deg C for the 1991 Mount Pinatubo eruption. To simplify and standardize the adjustments I’ve applied the same scaling factor to both the observed Sea Surface Temperature data and the model outputs. And I used the same adjustments for all subsets. As you will see, it slightly overcorrects in some instances and under-corrects a little in others. But since the adjustments are the same for the model outputs and instrument-based observations, they have no impact on the trend comparisons.
EAST PACIFIC SEA SURFACE TEMPERATURE COMPARISON
Figure 3 compares the Sea Surface Temperature anomalies of the East Pacific Ocean (90S-90N, 180-80W) to the scaled Sea Surface Temperature anomalies of the NINO3.4 region of the equatorial Pacific (5S-5N, 170W-120W). NINO3.4 Sea Surface Temperature anomalies are a commonly used index of the frequency and magnitude of El Niño and La Niña events, and I’ve scaled them (multiplied them by a factor of 0.22) because the variations in Sea Surface Temperature in that area of the equatorial Pacific are about 4.5 times greater than those of the East Pacific Ocean. As illustrated, the Sea Surface Temperature anomalies of the East Pacific mimic the NINO3.4 Sea Surface Temperature anomalies.
Figure 3
Figure 4 compares the observed Sea Surface Temperature anomalies of the East Pacific to the CMIP3 Multi-Model Mean for the same coordinates. The first thing that stands out is the difference in the year-to-year variability. The observed variations in Sea Surface Temperature due to the ENSO events are much greater than those of the Multi-Model Mean. Keep in mind when viewing the model-observations comparisons in this post that the model mean is the average of all of the ensemble members. And since the variations in the individual ensemble members are basically random, they will smooth out with the averaging. The average, therefore, represents the forced component (from natural and anthropogenic forcings) of the models. And it’s the forced component of the model data we’re interested in illustrating and comparing with the observations in this post, not the big wiggles associated with ENSO.
Figure 4
The difference in the linear trends between the Multi-Model Mean and the observations is also extremely significant. That is the focus of this post. The linear trend of the Multi-Model Mean is 0.114 deg C per decade for the East Pacific Ocean. This means, based on the linear trend of the Multi-Model Mean, that anthropogenic forcings should have raised the East Pacific Sea Surface Temperature anomalies, from pole to pole, by more than 0.34 deg C over the past 30 years. But the observed Sea Surface Temperature anomalies have actually declined. The East Pacific Ocean dataset represents about 33% of the surface area of the global oceans, and the Sea Surface Temperature anomalies there have not risen in response to the forcings of anthropogenic greenhouse gases.
THE REST-OF-THE-WORLD COMPARISON
The Sea Surface Temperature anomalies and Multi-Model Mean for the Rest-Of-The-World (Atlantic, Indian, and West Pacific Oceans) from pole to pole are shown in Figure 5. The linear trend of the multi-model mean shows that the models have overestimated the warming by about 23%.
Figure 5
But even that is misleading, because the observed Sea Surface Temperature anomalies only rose in response to significant El Niño-La Nina events, and during the 9- and 11-year periods between those ENSO events, the observed Sea Surface Temperatures are remarkably flat. This is illustrated first in Figure 6, using the period average Sea Surface Temperature anomalies between the significant El Niño events, and second, in Figure 7, by showing the linear trends of the instrument-based observations data between the 1986/87/88 and 1997/98 El Niño events and between the 1997/98 and 2009/10 El Niño events.
Figure 6
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Figure 7
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As you will note, I’ve isolated the significant El Niño events of 1982/83, 1986/87/88, 1997/98, and 2009/10. To accomplish this, I used the NOAA Oceanic Nino Index (ONI) to determine the official months of those El Niño events. There is a 6-month lag between NINO3.4 SST anomalies and the response of the Rest-Of-The-World SST anomalies during the evolution phase of the 1997/98 El Niño. So I lagged the ONI data by six months and deleted the Rest-Of-The-World SST data that corresponded to the 1982/83, 1986/87/88, 1998/98, and 2009/10 El Niño events. All other months of data remain.
Note: The El Niño event of 1982/83 was counteracted by the volcanic eruption of El Chichon, so its apparent role in the long-term warming is minimal.
And what do the climate models show should have taken place during the periods between those ENSO events?
For the period between the 1986/87/88 and the 1997/98 El Niño events, Figure 8, the model mean shows a positive linear trend of 0.044 deg C per decade, while the observed linear trend is negative, at -0.01 deg C per decade. The difference of 0.054 deg C per decade is significant.
Figure 8
The difference between the linear trends is even more significant between the El Niño events of 1997/98 and 2009/10, as shown in Figure 9. The linear trend of the observations is basically flat, while trend of the models is relatively high at 0.16 deg C per decade.
Figure 9
Keep in mind that the model mean, according to the IPCC, represents the anthropogenically forced component of the climate models during the period of 1981 to 2011. Unfortunately for the models, there is no evidence of anthropogenic forcing in the East Pacific Ocean Sea Surface Temperature data or in the Sea Surface Temperature data for the Rest Of The World.
Let’s subdivide the Rest-Of-The-World data even more. This will illustrate why the Sea Surface Temperature anomalies between the significant ENSO events are flat.
THE NORTH ATLANTIC AND THE SOUTH ATLANTIC-INDIAN-WEST PACIFIC SEA SURFACE TEMPERATURE ANOMALY DATA
Figure 10 is a map that shows how the data for the additional discussions were subdivided. Basically, this was done to isolate the North Atlantic from the additional ocean basins in the Rest-Of-The-World data. And the observed Sea Surface Temperature anomalies for those two subsets are shown in Figure 11. As illustrated, the linear trend of the North Atlantic Sea Surface Temperature anomalies is significantly higher than the linear trend of the South Atlantic-Indian-West Pacific subset. This higher trend in the North Atlantic data is caused by the additional mode of natural variability known as the Atlantic Multidecadal Oscillation. And as we will see, the forced component of the models (the model mean) does not account for the additional variability in the North Atlantic attributable to the Atlantic Multidecadal Oscillation.
Figure 10
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Figure 11
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Note: The North Atlantic Sea Surface Temperature anomalies for datasets like the Atlantic Multidecadal Oscillation data are normally depicted by the coordinates of 0-70N, 80W-0. Here they include 0-90N, 80W-40E to capture the Mediterranean Sea and corresponding portion of the Arctic Ocean leftover from the other subsets. The additional surface area has little impacton the North Atlantic Sea Surface Temperature anomaly data presented here. But to differentiate it from the other versions of the North Atlantic data, I’ve called it “North Atlantic Plus” in the graphs.
“NORTH ATLANTIC PLUS” COMPARISON
The North Atlantic is the only ocean basin where the models underestimate the long-term trend of the satellite-era Sea Surface Temperature data. See Figure 12. (Also refer to Part 1 and Part 2of an earlier two-part post comparing the Reynolds OI.v2 Sea Surface Temperature dataset to the same CMIP3 Multi-Model Mean, but note that the data in those posts have not been adjusted for volcanic aerosols.) Based on the linear trends, the models have underestimated the warming of the North Atlantic by nearly 35%. Again, the North Atlantic has an additional mode of natural variability called the Atlantic Multidecadal Oscillation or AMO. It seems very obvious that the multi-model mean fails to hindcast and project this additional variability.
Figure 12
And for those interested, I’ve also provided graphs that compare the model mean and observed trends between the significant El Niño events. As shown in Figure 13, the models underestimate the warming that took place between the El Niño events of 1986/87/88 and 1997/98. And as illustrated in Figure 14, the models overestimated the rise in North Atlantic Sea Surface Temperatures between the 1997/98 and 2009/10 El Niño events.
Figure 13
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Figure 14
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Let’s take a look at the South Pacific, Indian, and West Pacific comparison. As many of you are aware, I like to save the best for last.
SOUTH ATLANTIC-INDIAN-WEST PACIFIC COMPARISON
Figure 15 compares long-term observed Sea Surface Temperature anomalies and the Multi-Model Mean for the South Atlantic, Indian, and West Pacific Oceans. This is basically the portion of the “Rest-Of-The-World” dataset that is not included in the “North Atlantic Plus” data. As illustrated, the trend of the Multi-Model Mean is about 62% higher than the trend of the observed data. That is, the forced component of the models has over predicted the rise in Sea Surface Temperature anomalies for this subset by a substantial amount.
Figure 15
But the long-term trends are again misleading. The South Atlantic-Indian-West Pacific Sea Surface Temperature anomalies only rise during the significant El Niño events of 1986/87, 1997/98, and 2009/10. Between those events, the Sea Surface Temperature anomalies drop.
Figure 16 compares the observed South Atlantic-Indian-West Pacific Sea Surface Temperature anomalies to the Multi-Model Mean between the 1986/87/88 and 1997/98 El Niño events. The anthropogenic forcings have driven the model-mean upwards during this period, but the linear trend of the observations show that Sea Surface Temperatures declined. And the difference of 0.093 deg C per decade is a major difference. But that’s small compared to the difference between the linear trends of the observations and the model mean for the period between the El Niño events of 1997/98 and 2009/10. That difference is almost 0.18 deg C per decade.
Figure 16
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Figure 17
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CLOSING COMMENT
As illustrated in the two earlier posts that use these same datasets (see here and here), the Multi-Model Mean of the CMIP3 coupled ocean-atmosphere climate models do not hindcast and project the Sea Surface Temperature anomalies in any ocean basin, when the data is presented on times-series basis and on a zonal mean (latitude-based) basis. (The model mean of the West Pacific subset may look good on a time-series basis, but not on a zonal mean basis.)
This post confirms the Multi-Model Mean (the forced component of the climate models) does a poor job of hindcasting and projecting the actual rise in global Sea Surface Temperature anomalies, when the data is broken down into two logical subsets: the East Pacific Ocean and the Rest-Of-The-World. The post also illustrates the very basic reasons for that rise.
The models used by the IPCC for their hindcasts and projections assume that anthropogenic greenhouse gases drove the rise in Sea Surface Temperature anomalies from November 1981 to present. This is illustrated by the model mean, which represents the forced component of the models.
But the Sea Surface Temperature anomalies of the East Pacific Ocean (90S-90N, 180-80W) have not risen in 30 years. Refer to Figure 18.
Figure 18
And for the Rest-Of-The-World (90S-90N, 80W-180), Figure 19, the Sea Surface Temperature anomalies only rose during, and in response to, the 1986/87/88, 1997/98, and 2009/10 El Niño events.
Figure 19
There is no evidence that anthropogenic greenhouse gases have had any impact on the East Pacific Sea Surface Temperature anomalies (90S-90N, 180-80W) or on the Sea Surface Temperature anomalies for the Rest Of The World (90S-90N, 80W-180).
ABOUT: Bob Tisdale – Climate Observations
SOURCES
The model mean data is found at the KNMI Climate Explorer Monthly CMIP3+ scenario runs webpage. The Reynolds OI.v2 Sea Surface Temperature anomaly data is available through the NOAA NOMADS website here. And the GISS aerosol optical depth data used to make the adjustments for volcanic aerosols can be found at the Stratospheric Aerosol Optical Thickness webpage, specifically this data.
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John B says: “The is no rationale behind the assumption that El Nino events cause a trend. For the opposite take on this, that a look at…”
Your statement indicates YOU do not understand ENSO, and that’s why I included links to the introductory post at the beginning:
http://bobtisdale.wordpress.com/2010/08/08/an-introduction-to-enso-amo-and-pdo-%e2%80%93-part-1/
And the gif animation and post at SkepticalScience you linked further display the fact that you only looked at the graphs above and didn’t bother to read my post or the posts that I linked that discussed, illustrated, and animated the processes that cause the upward shifts that I’ve presented. If you had, and if you had understood them, you would not have presented those SkepticalScience links.Here are the links to my posts that you obviously failed to read:
http://bobtisdale.wordpress.com/2011/07/26/enso-indices-do-not-represent-the-process-of-enso-or-its-impact-on-global-temperature/
And here’s part 2:
http://bobtisdale.wordpress.com/2011/08/07/supplement-to-enso-indices-do-not-represent-the-process-of-enso-or-its-impact-on-global-temperature/
And please don’t come back here with links to the nonsensical SkepticalScience posts that say that ENSO is a cycle and as such cannot contribute to a positive trend. The authors of those posts simply broadcast their misunderstandings about ENSO with those statements. They think ENSO is an index. They think ENSO only relates to little rectangular regions along the equatorial Pacific where Sea Surface Temperatures are measured and called ENSO indices. Refer to the last two posts I linked for you above.
Have a nice day…and a happy holiday.
Well, the thing is the mechanism that drives El Nino / La Nina are pressure differences between the Eastern and Western Pacific that increase or decrease winds. The situation on the opposite side of the globe tends to be different (the opposite). And don’t get me wrong, I love reading Tisdale. That is where I learned that and how I understood how La Nina is actually a net increase in ocean energy even though the surface is cooler!
I have a lot of respect for Mr. Tisdale. I am just pointing out that the graph in Figure 19 shows the post 2010 El Nino trend is already established before the El Nino. And I believe it was the 2008 La Nina that did it. We normally can’t see that because we often go directly from El Nino into La Nina and so the impact of the La Nina is to moderate the recovery from the previous El Nino. So looking at that on a graph, it would be a natural conclusion to believe that the El Nino caused the change in trend because you see one trend before the El Nino and a different after. That would be a normal conclusion to reach. But I think it is the La Nina that comes immediately after the El Nino that prevents the recovery to the old trend.
It just so happens that in the data series in figure 19 we happen to “catch ” a significant La Nina happening without a strong preceding El Nino and we see the new “rest of the world” trend established during that event. There is, as far as I can see, no difference in trend in the 1.5 years or so before the 2010 event and the trend immediately after. But we might NOW be pushing that trend up because now we are in a protracted La Nina condition which will add energy to the overall system.
I think it is La Nina that boosts the trend, not El Nino.
El Nino is a net loss of energy from the sea to the atmosphere. La Nina is a net gain.
Let me try to fight mey way past the wriggly lines and get this into terms I can understand.
“IPCC say CO2 make sea get hot. Sea no get hot. IPCC full of it.”
Is that it?
crosspatch says:
December 19, 2011 at 4:55 pm
“”El Nino is a net loss of energy from the sea to the atmosphere. La Nina is a net gain.””
Given a multi-modal system isn’t the gain from La Nina diminished from the net loss of El Nino differences in the east pacific at South America, if we are talking about a global energy system? I would possibly agree there are regional energy gains during these phenomena.
I do understand your conviction that winds drive the La Nina/El Nino mechanism, and yes, air pressure has that effect on the Ocean and Ocean circulation, however, IMHO a stronger driver for La Nina/El Nino is the SST itself and a tipping of it between the east and west pacific waters, due to Temp transport (convection) through the Ocean undercurrents. Thanks for your patience, crosspatch, I’m still learning.
For anybody interested in Australian temps, it might be worth looking at the BoM’s 14 coastal SEAFRAME stations that monitor various trends including sea air temperatures since 1991. The temps are all packaged at http://www.waclimate.net/sea/sea-air-temperatures.html
The 14 stations combined might suggest a temp increase around .2C over the past 20 years but the data is worth closer examination …
• The general trend was for northern warm latitudes to have cooling sea air temperatures, in line with records from the land stations, with southern stations increasing in temperature. All three Western Australia stations were flat or slightly cooler since 1991 despite claims the Indian Ocean has been warming.
• The overall increase was mostly because of Australia’s populated south east quarter, the exception being the Cocos Islands. For example, Portland Victoria sea air temperatures would seem to have gone up by about 1C since 1995.
Is there something akin to nino3.4 for the equatorial Atlantic? It would probably be something smaller but I would be interested in the sea surface temperatures for a region that is analogous to Nino3.4. I want to see if there are cycles similar to Nino/Nina only in the Atlantic (lets call them Bubba and Sissy … though it might be BS for short, I don’t know yet). I am wondering something.
Usually when we have somewhat opposite conditions in the equatorial Pacific and Atlantic. What I am wondering is if we ever get what I might call a “super cycle” where we have strong trades or weak trades in BOTH regions at the same time and what their impact might be. So like maybe a Nino/Bubba or a Nina/Sissy rather than the two being out of phase with each other.
read all:
19 Dec: NYT: Dot Earth: Andrew C. Revkin: Climate Panel Needs to Follow its Own Advice
I believe it’s time for Rajendra K. Pachauri to take a new approach to discussing climate change or leave the chairmanship of the Intergovernmental Panel on Climate Change after nearly a decade in that position. There is an unavoidable and counterproductive blurriness to the line between his personal advocacy for climate action — which is his right as an individual — and his stature as the leader of the panel, which was established in 1988 as “a policy relevant but policy neutral organization.”
The latest crystallization of this problem came last Thursday, when Pachauri participated in a meeting on “Extreme Climate Risks and California’s Future,” organized by California Gov. Jerry Brown…
http://dotearth.blogs.nytimes.com/2011/12/19/climate-panel-needs-to-follow-its-own-advice/
more models…
19 Dec: Miami Herald: Pat Brennan: NASA: Warming will transform natural world
Global warming could bring a major transformation for Earth’s plants and animals over the next century, a NASA study says, driving nearly half the planet’s forests, grasslands and other vegetation toward conversion into radically different ecosystems.
The ecological stress could give a boost to invasive species, but at the expense of natives, reducing the diversity of plants and animals overall.
And humans are likely, almost literally, to cut them off at the pass: When plants and animals attempt to survive by shifting their geographical ranges, as they have in past episodes of climate change, they’ll be blocked by farms and cities.
“If half the world is driven to change its vegetation cover, and meanwhile, we’ve fragmented the surface of the Earth by putting in parking lots and monoculture agricultural zones and all these other impediments to natural migration, then there could be problems,” said lead author Jon Bergengren, a global ecologist who was a postdoctoral researcher at Caltech when he did the study…
The far-reaching forecast spans three centuries and relies on powerful computer models of Earth’s climate and vegetation.
The scientists, including Duane Waliser of the Jet Propulsion Laboratory in Pasadena, used a model devised by Bergengren that can forecast the likely community of plants that would develop in any given type of climate.
The model relies on 110 plant types to represent the thousands of plant species on Earth.
They plugged in 10 different climate simulations based on 2007 predictions by the Intergovernmental Panel on Climate Change…
http://www.miamiherald.com/2011/12/19/2553141/nasa-warming-will-transform-natural.html
It is impossible to have a La Nina without strong trade winds. It just can’t happen. Same as you can not have an El Nino without slack trade winds, that can’t happen, either.
Something has to blow that surface water Westward. Something has to stop blowing it.
Oh, and I found the perfect Christmas gift for your favorite climate skeptic:
“Little Ice Ages, Ancient and Modern,” vols. 1 and 2, 2nd ed., by J. M. Grove
They’ll probably set you back about $600 or so, though.
Well, all they have to do is look at what the vegetation was during the Holocene Climate Optimum and that is what it would be like if it warmed considerably from now. Another way of looking at it is that we are undoing the damage that has been done due to global cooling since that time.
Bob,
I always enjoy your posts, but this quote from you is especially funny:
“But the long-term trends are again misleading.”
____
I understand your point about El Nino’s and the “step up” in SST’s during these periods, and your notion that SST’s are flat to declining in between, but long-term trends are what we are looking for if the anthropogenic signal is to be seen. Suppose, for sake of argument, that I accept the notion that the increase in SST’s and perhaps even OHC has all been related to El Nino’s. You must have some “step down” period, where we see, more La Nina’s than El Nino’s, and hence, we’ll see declining OHC, right? I suppose this would be a period of a cooler PDO, and perhaps a cool AMO as well? The problem with this notion is that globally, oceans absorb more heat then they release during La Nina’s, thus OHC will increase during such a “step down” cycle. We see this quite readily in the data. So, when would we expect to see OHC decrease, as it has not been during your El Nino driven “step up” periods? The key point here is that SST’s are not the key indicator for anthropogenic warming of the oceans, but rather OHC is, and is continues to rise throughout the full ENSO cycle over the long-term, and this is most certainly not a misleading trend. Please explain when and how you expect to see the real measure of energy in the ocean, OHC (down to the deepest levels we can accurately measure), begin to decrease over the long-term, as it has not for many decades.
Bob, As always, it is a pleasure reading your work. It is very refreshing to see you using volcanic adjusted SST’s. What you have provided here a clue to the physical mechanisms which support the conclusions of Lindzen, Christy and Spencer… that global temps will rise about 1C per doubling of CO2, not the multitudes suggested by IPCC and etc models.
What I would point out is that the surface water (slightly warmed by anthropogenic greenhouse gases, and solar since there was a major event during the same time) is blown west by the trades where it accumulates in the warm pool (La Nina) then is discharged by Kelvin waves back into the Nino regions (El Nino), particularly the Large El Ninos (82, 98, 2010), then to higher latitudes.
For crosspatch and the rest of the gang, I can see that some education in ENSO would be helpful, please take some time to read El Nino for dummies here: http://roqtock.com/id9.html
R. Gates says:
“but long-term trends are what we are looking for”
And you’ll have them in a few thousand years, assuming we maintain a database that long.
UG! I’m such the typoe master tonite… ENSO for dummies starts here:http://roqtock.com/id8.html
Bob, I suppose I could have articulated that last part better .(long day).. The portion of surface water warmed by AGW is stored in the warm pool, then discharged during the El Nino’s, especially the bigger ones. That would explain why there is a step function to the warming.
Lotsa yummy sausage-making, here! But there is an obvious conclusion to be drawn, which is evaded.
Therefore: anthropogenic forcings are negative.
Simples!
mmikeccMikeC says:
December 19, 2011 at 8:58 pm
What you have provided here a clue to the physical mechanisms which support the conclusions of Lindzen, Christy and Spencer… that global temps will rise about 1C per doubling of CO2, not the multitudes suggested by IPCC and etc models.
——–
I would suggest Bob’s analysis does no such thing. His is an analysis of step-wise increases in SST’s during El Nino cycles and the notion that that surface heat continues on long after the event is officially over. It makes no connection to climate sensitivity per doubling of CO2. Furthermore, the more important metric of energy in the oceans, Ocean Heat Content, shows large increases during the last decade when atmospheric temps have been flat. This of course makes sense, as La Nina’s have been more dominant over the past decade and it is during such periods that the oceans as a whole, retain more heat than they release to the atmosphere. What Bob has yet to explain is when he expects ocean heat content to begin to fall once more as it has been rising pretty steadily for more than 3 decades, through multiple El Nino and La Nina cycles. Simple put, the oceans have been gaining far more heat then they have been able to release during the past 30+ years.
The site is rather, uhm, cartoonish. Maybe I am too much of a dummy to get much out of it.
Point is when you have an El Nino, yes, the surface temperature is warmer but that is because of a reduction of evaporation from slack trades. At the same time during an El Nino you get more clouds over the equatorial Pacific so a net decrease in the amount of sunlight actually reaching the sea surface or a net decline in energy to the ocean.
During a La Nina you get more evaporative cooling due to stronger winds but you also get more direct sunlight due to a lack of clouds. La Nina periods are sunnier than normal.
So overall net energy increases in the entire ocean system during La Nina even though the equatorial surface temperatures are lower. The warm pool holds that energy. As the Indian Ocean heats up, some of that warmer water will slip out in a shallow circulation around Africa and head up toward the Caribbean and eventually become the Gulf Stream. Its going to take about 4 to 6 months for that heat in the Indian ocean warm pool to begin arriving in the sub-arctic. Figuring Nino generally peaks in about January-ish, we should see a warm anomaly appearing in the North Atlantic sometime around May.
So take this image:
http://www.osdpd.noaa.gov/data/sst/anomaly/2007/anomnight.10.1.2007.gif
That’s October 1 2007. You see the warm pool building in the Indian Ocean and you notice the warm anomaly around the tip of Africa. Also notice the warm water South of the Aleutians and off the coast of Newfoundland.
Now: http://www.osdpd.noaa.gov/data/sst/anomaly/2008/anomnight.3.3.2008.gif
By March 2008 you have the warm pool gone in the Indian Ocean but notice the heat anomaly off the tip of Africa and up the Atlantic Seaboard of the US.
http://www.osdpd.noaa.gov/data/sst/anomaly/2008/anomnight.7.3.2008.gif
By July you have warm water across the North Pacific all the way to off the coast of the Pacific Northwestern US as the equatorial Pacific begins to warm up.
Lets jump ahead to August 2009 where we have an pretty significant El Nino building.
http://www.osdpd.noaa.gov/data/sst/anomaly/2009/anomnight.8.3.2009.gif
Notice that now we have exactly the opposite condition in the equatorial Atlantic. We have an El Nino in the Pacific and a “Sissy” in the Atlantic. Weak trades in the Pacific, strong trades in the Atlantic. The Atlantic is much smaller at that point. It can’t really build much of a warm pool except in the Gulf of Mexico.
By December 2009 we have a “full blown” El Nino:
http://www.osdpd.noaa.gov/data/sst/anomaly/2009/anomnight.12.3.2009.gif
Northern Pacific is cool. Look off the West Coast of South Africa / Namibia … we now have a cool anomaly. Still cool-ish in the equatorial Atlantic. North Atlantic generally cool-ish except right along the New England coast which is due to a weather feature that has been sitting there for the past few winters making New England rather mild.
Now lets look at March 2010 http://www.osdpd.noaa.gov/data/sst/anomaly/2010/anomnight.3.1.2010.gif
El Nino beginning to dissipate. Atlantic, particularly the Gulf of Mexico is cool. Trades are beginning to pick up.
Thank you Bob and Merry Christmas. This will take more than one read to fully digest.
Crosspatch, Please take a look at the cartoonish site again. Your entire premise is mistaken. You are confusing SST’s with warm pools and etc. The entire ENSO is related to some very specific physical mechanisms which occur in the Nino regions.
R Gates, quite to the contrary. Look at the amount of temperature change over time as compared to the model runs. His results show clearly that there has been an increase in temperature over time, just that it has occurred in steps. My point was that the warmer surface water from AGW (and probably solar) accumulates in the warm pool until it is discharged by Kelvin wave(s) during El Nino events.
Well, one thing I have notice is that changes in ocean heat content seem to lag Nino3.4 by a year. For example
http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/heat_content55-07.png
Notice the peak just now happening even though we are in a La Nina condition? But look at other peaks. Look at that big one in 2004. It’s a year after the 2003 El Nino. 2001 dip? A year after the 2000 La Nina.
So ocean heat content seems to lag Nino3.4 by actually pretty close to 12 months.
The oceans control the clouds which control insolation which controls the oceans which …
Sing along: “La Nina’s connected to the trade winds, …”
Crosspatch and your point is!! Anthony’s site is cartoonish and you come across as a smart arse. Is that what you intended to convey. If you have good solid points to make it is not necessary to be derogative, thus your post is less than it otherwise could have been.