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Yesterday’s press release from the UK Met Office introduces 2 new papers in Geophysical Research Letters which explain the recent lack of ocean warming, approximately since 2003. Most of the pause in warming is attributed to natural ENSO (El Nino-Southern Oscillation, that is, El Nino and La Nina) activity.
First of all let me say I agree with them. It is a step forward for the “skeptics” side of the global warming debate that the climate modelers finally admit that nature can have a role in global warming and cooling episodes… although they seem to be limiting that role to approximate 10-year time scales.
This at least a step in the right direction, since previously climate modelers would not admit to ENSO causing much more than year-to-year variability. Our own ocean modeling research, in progress, is suggesting that about 30% of the ocean warming trend since the 1950s is due to a shift to more frequent El Nino activity in the second half of that period, while the lack of ocean warming in the last 8 years appears to be from a shift back to La Nina activity.
So, the new GRL papers are one more step toward what some of us have been saying all along: Mother Nature is perfectly capable of causing her own climate change. The big question is: HOW MUCH of the ocean warming in the last 50 years has been due nature?
SOME UNANSWERED QUESTIONS
While I am supportive of these 2 papers from the standpoint of acknowledging the roll of El Nino and La Nina in global temperature change, these are just the first 3 issues that come to mind.
1) Both studies discuss the fact that even in the climate models, one does not necessarily expect warming in every decade in response to increasing CO2.
QUESTION: Since this is something that should have been known for about the last 20 years of climate modeling activities, why did they wait till warming stopped to mention it?
2) As you can see in Fig. 1 from the Katsman and Oldenborgh paper, they ignored the first 20 years of ocean heat content data, for the obvious reason that the observations showed no warming, while all of their model simulations indicated considerable warming. The reason they gave was a lack of good data before 1969.
QUESTION: What if the ocean observations DID show warming during those first 20 years? Would those years have been included in the analysis then, since they agreed with the model? Isn’t this rather obvious cherry picking?
3) In the same article, we see the following statement regarding the specific cause of a lack of ocean warming since 2003: “During 2002–2007, a series of El Niño events occurred, which probably yielded a larger than average upper ocean heat loss…” Excuse me? I believe they have this backwards…
QUESTION: If El Nino leads to a net LOSS of upper ocean heat, then why during this same period does a positive MEI index (indicating El Nino) precede WARMING of the 0-700 m ocean layer, as shown in the following plot (click for large version)?
This is how we were able to match the Levitus ocean heat content variations… by including a heat storage term where El Nino leads to heat gain, and La Nina leads to heat loss:
And, since there has been more frequent El Nino activity since the 1980’s, this is consistent with some of the warming being natural. Then, since 2000, this has begun to switch to more La Nina’s, resulting in the most recent slowdown in ocean warming.
What I fear is that because of this mistake in interpretation (the authors were merely postulating why recent warming stopped based upon the statistical behavior of climate models), that others will now point to that publication and claim it showed El Nino causes net cooling of the ocean, not warming. Sheesh.
Oh well, at least these papers represent at least a partial retreat from the IPCC’s anthropocentric view of the climate system.
It may well be that models El Ninos lead to heat loss (rather than gain) if the models “ENSO” is not anything like that in the real world but is called such simply because they have some oscillation of equatorial pacific sea surface temperatures in their models. I would bet good money that the causes and consequences of “ENSO events” that occur in models are not at all similar to the observed relationships of the climate with ENSO variations.
Does anyone in climate science have an answer why that particular phenomenon is so important anyway? One would think sea surface temperatures anywhere would have distant effects, but most of the “wiggles” even in global climate are dominating by variations that originate in the Tropical Pacific Ocean. Now why wouldn’t other places in the world similarly drive fluctuations?
It is quite true that El Nino should transfer energy from ocean to air for a reduction of ocean heat content and a corresponding increase in tropospheric air temperatures.
Similarly La Nina should withold energy from the air for an increase in ocean heat content for a corresponding decrease in tropospheric air temperatures.
However that is not the way it is working out.
During the late 20th century ocean heat content rose despite the long run of powerful El Ninos.
Since 2000 ocean heat content has failed to rise despite a shift to negative PDO with more Lsa Ninas.
So it is clear that another factor is involved and in my opinion that other factor is the level of solar activity.
If the sun is active the mid latitude jets move poleward to reduce global cloudiness and albedo to let more energy into the oceans and if the level of solar activity is high enough that can inject more solar energy into the oceans than is lost by stronger El Ninos. That is what happened in the late 20th century.
Since 2000 the drop off in solar activity has been remarkable. Thus the lower level of solar activity has pushed the jets equatorward to increase global cloudiness and albedo to allow less energy into the oceans so that despite the negative PDO with slightly stronger La Ninas there is not enough solar energy entering the oceans to add to ocean heat content.
We are fortunate (for diagnostic purposes) that the fall in solar activity since the peak of cycle 23 has been so large. If it had been less substantial the signal would have been more equivocal.
As it is the link between solar and oceanic behaviour on ocean heat content (and therefore tropospheric air temperatures) is in my opinion pretty obvious.
The global climate varies with the shifting of the climate zones. They shift in response to the net outcome at any given time of the balance between the level of solar activity and the phase of the oceanic oscillations.
The visible manifestation of that balance is the behaviour of the surface pressure distribution and in particular the latitudinal position of the mid latitude jets which directly affect total global cloudiness and albedo.
That is the only scenario that fits the late 20th century increase in ocean heat content DESPITE strong El Ninos AND the recent cessation of ocean warming DESPITE a negative PDO with more La Ninas.
For the future I anticipate a continuing quiet sun along with a continuing and progressively more negative PDO with an accelerating drop in ocean heat content DESPITE that negative PDO.
That decreasing ocean heat content will continue to feed into a progressively cooler troposphere until the sun becomes more active and/or the PDO turns positive.
Is there any other hypothesis that fits the observations ?
“most of the “wiggles” even in global climate are dominating by variations that originate in the Tropical Pacific Ocean. Now why wouldn’t other places in the world similarly drive fluctuations?”
Because the whole process starts in the Equatorial Pacific where solar energy input to the system is strongest.
The solar effects in the Pacific then spread around the world in stages through the separate ocean basins finally ending up either in the Arctic Ocean or in the Antarctic circumpolar circulation.It is no coincidence that the maximum Arctic ice melt occurrred about ten years after the record 97/97 El Nino.
The ENSO effect occurs in pulses. The reason being that because the Inter Tropical Convergence Zone (ITCZ) is always on average north of the equator there is an imbalance of solar energy input either side of the equator. That imbalance periodically accumulates to a level where it forces an El Nino event to restore the system equilibrium.
As far as I know I am the only person to suggest such a cause for the ENSO phenomenon.
The frequency and intensity of El Nino events is driven by the intensity of solar insolation to the oceans and that in turn is affected by solar effects on the polar vortices which affect global cloudiness and albedo which I have described in detail elsewhere.
Do not confuse PDO which is a statistical derivative of ENSO with the Pacific Multidecadal Oscillation (PMO).
I think it likely that PMO is driven by internal oceanic mechanisms rather than solar influences but solar influences are imposed upon the internal oceanic cycling to affect the relative strengths of El Nino and La Nina ftom one PMO cycle to another.Thus the sun would have driven the oceanic warming from LIA to date and thereby transferred energy to the troposphere in a step by step pattern from one PMO cycle to the next. Most likely the reverse occurred from MWP to LIA.
In any event the tropospheric temperature are just a side effect of the net balance between solar and oceanic effects with CO2 and other GHGs just having a miniscule effect compared to natural variability.
Responding to the post of Stephen Wilde of August 5, at 4:55 PM.
Stephen Wilde proposes that the “wiggles” originate locally in the Tropical Pacific Ocean, and he attributes their origin to variations in solar activity. If he is right, this would be an example of how an external driver can provide information that leads to understanding of the workings of a dynamical system. External drivers cause phenomena that can be traced causally through the system, as Stephen is proposing to be doing here. This is a way to untangle the “feedback” problem. Christopher Game
Roy: Divide the oceans into subsets to see where El Nino events cause losses and where they cause gains. You noted that your model suggests that ENSO is responsible for 30% of the rise in OHC since 1955. That sounds light. Keep in mind that ENSO also redistributes heat FROM the tropical Pacific, in addition to discharging and recharging within it.
(I’m providing webpage addresses to posts, not links, in an attempt to bypass your spam filter. So you’ll have to cut and paste the addresses to your browser.)
[bobtisdale.wordpress.com/2009/09/05/enso-dominates-nodc-ocean-heat-content-0-700-meters-data/]
Similar to SST, the AMO/AMOC should explain much of the disparity between the rise in North Atlantic OHC and the OHC rise for the rest of the oceans. (The North Atlantic covers only 11% to 13% of the global ocean surface area but it represents a whopping 34% of the rise in OHC since 1955.) But there are sea level pressure and ENSO components to the rise in North Atlantic OHC as well.
[bobtisdale.wordpress.com/2009/10/04/north-atlantic-ocean-heat-content-0-700-meters-is-governed-by-natural-variables/]
And there’s a sudden upward shift in North Pacific OHC in the late 1980s. That appears to have been caused by a shift in North Pacific Sea Level Pressure:
[bobtisdale.wordpress.com/2009/12/30/north-pacific-ocean-heat-content-shift-in-the-late-1980s/]
Regards
Stephen Wilde says: “It is quite true that El Nino should transfer energy from ocean to air for a reduction of ocean heat content and a corresponding increase in tropospheric air temperatures.
“Similarly La Nina should withold energy from the air for an increase in ocean heat content for a corresponding decrease in tropospheric air temperatures.
“However that is not the way it is working out.”
Stephen, if your understandings of OHC variability relied on data instead of conjecture, you’d see that it is precisely how it works. Your overly simplistic explanation misses many portions of the ENSO process and misses the fact that the AMO/AMOC-related decrease in North Atlantic OHC since 2005 is responsible for much of the flattening of global OHC since 2003. But you wouldn’t know that since you don’t bother to examine data.
Roy: Your comparison graph (Forcing-Feedback-Diffusion Model vs Levitus 0 to 50 meter depth) clearly shows that the variability of the top 50 meters is more similar to SST variability than it Is to the variability of OHC for 0-700 meters. The 1997/98 El Niño does not appear as an upward spike in the Levitus et al OHC data for the depths of 0-700 meters, but it appears as one in your 0-50 meter data. Here’s a comparison graph of standardized Global SST vs standardized global OHC (0-700 meters):
[i51.tinypic.com/64frf4.jpg]
Logically, the difference between the standardized global OHC (0-700meters) and SST data is a function of ENSO:
[i54.tinypic.com/262s5cp.jpg]
Those graphs are from this post:
[bobtisdale.wordpress.com/2011/05/22/sea-surface-temperature-versus-ocean-heat-content-anomalies/]
Roy: One last thing: With regards to your lead/lag correlation graph, there is an upward shift in the NODC Global OHC data in 2003 that may be skewing your results. The upward shift in 2003 may result from the addition of the ARGO data during that period, call it a splicing error. Prior to 2003 there were very few observations at depth south of 30S. Then with the introduction of the ARGO floats, they started to have lots more data in the mid-to-high latitudes of the Southern Hemisphere. The NODC reduced that upward shift with their October 2010 revisions, but it still exists. Assuming you’re working with the most recent rev. level of the NODC OHC data, if you were to plot that lead/lag correlation from 2004 to 2011 (ARGO was pretty much in place by the end of 2004), do you still get the same results?
Dr. Spencer, I am pleased that you have asked those pertinent questions, but I suspect that they will remain unanswered.
To be fair, it isn’t entirely true to say that no models have predicted a pause in temperature increase over a 10 year period.
Actually the multi-model mean of the IPCC “commitment” scenario, projects a slight fall in temperatures between 2008 and 2017.
Unfortunately however, that scenario is based on zero growth in greenhouse gas levels after the year 2000, and it also projected a rise in temperatures between 2002 and 2011, when, using HadCRUT3 figures, temperatures have actually fallen.
Of course, some individual models have done better than the multi-model mean and 4 of the 16 models in the “commitment” scenario actually projected lower temperatures by 2010 than was actually the case.
The problem is in identifying which models are likely to be the most accurate in the future, since some of the models with lowest temperatures at the start of the century have the highest at the end. I suspect that much of the apparent accuracy of some of the models is entirely due to random chance, rather than anything else.
It makes sense that El Ninos lead to heat gain and La Ninas to heat loss,and a cold PDO corresponds to more La Ninas. According to a paper done by Ian Mason, the state of the PDO, can be tied into the sun’s position about the the center of mass of the solar system.
It is also striking that at times of a prolong solar minimum period of activity the position of the sun about the center of mass of the solar system, is in the same position which seems to give a rise to a cold PDO.
It seems like it is still the sun, an external force which sets the stage for the oceanic heat content.
ON ANOTHER NOTE: Let’s see if any major geological activity will be following the recent solar storm that took plaCe around 00z Aug.06.
I say there is a good chance some major geological event will take place between now and Aug13.
DR. SPENCER IS 100% CORRECT IN HIS COMMENTARIES ON THIS SUBJECT AS FAR AS SOI INDEX EFFECTS ON OCEAN HEAT CONTENT.
Ray;
Chance, indeed. In fact, if you’re categorizing model predictions into the 3 lower, unchanged, and increased buckets by 2011, 4 out of 16 is barely even chance level accuracy.
This coming article on the sea-ice-albedo-feedback in light of changing cloud cover may be of interest:
http://www.agu.org/pubs/crossref/pip/2011JD015804.shtml
Please stop posting in off topic journals and use the peer review system correctly you nonce.
I like Roy’s rational and rigorous analysis of all the various facets of the global warming debate. I follow it all carefully.
But isn’t the entire debate redundant?
If the global temperature is rising, and continues to do so, and it is part of a natural cycle, THERE IS NOTHING WE CAN DO ABOUT IT
Ditto, but it is manmade because of fossil fuel burning, again, THERE IS NOTHING WE CAN DO ABOUT IT
The global economy works on steady growth – each year there are more of us, and we produce, eat and consume a bit more per person than we did the year before. That way, we avoid recession (most of the time) and we are all, by enlarge, employed. We do that by using around 2% or 3% more energy globally than the year before. And we do that by burning more oil, gas and coal.
To pretend that we could even keep up with half the annual required increase with new wind, wave, etc. etc. is simply a lie. We will HAVE to keep increasing fossil fuel burning. Any small reductions in the anual increase we can achieve with our renewables will have no measureable impact on the wrming (if that’s the cause)
If we don’t keep on burning? If we hold energy use constant, or even decrease it? Then the result is a huge worldwide slump. It’s as delicate as that – mass unemployment, deflation, wailing and gnashing of teeth.
We have no options. No Gov., or collective like the EU, will take a decision to limit energy growth – it would be suicide. So we have to keep burning, whilst playing about at the edges with renewables, maybe increasing 1% of the total required each year(but losing ground against growing demand) If it heats up the planet, then hard luck – our children’s children will just have to cope. We can’t stop it without shooting the present generations in the foot.
It will all end when we cannot mine or extract at a sufficient rate to match the demand, and the price gets higher and higher. That could be in 10 years, or 50 years, I don’t know. So the fossil fuel burning will then level, or even decline, and we will be desperately building dozens of nuclear power plants. But the motive will not be global warming (if fossil fuels are indeed the cause), it will be price, supply and a worldwide slump – with war and pestilence in abundance.
I claim that we could stop debating global warming, disband all the agencies and committees, and save a lot of money. We (Man) is on path to a summit, then a long and painful crash – it’s a plain as day. We expand at an alarming rate, seek ever longer lifespans, rape the planet for all it has, consume, play and reproduce for pleasure, etc. It cannot be sustainable, and worrying about whether the planet will get warmer, for any reason, will be well down the list of concerns for our future generations.
Keith Stevens (UK)