Arguments
Trenberth can't account for the lack of warming
The skeptic argument...
Trenberth can't account for the lack of warming
in one e-mail, a top "warmist" researcher admits it’s a "travesty" that "we can’t account for the lack of warming at the moment." As it happens, the writer of that October 2009 e-mail—Kevin Trenberth, a lead author of the warmist bible, the 2007 Intergovernmental Panel on Climate Change (IPCC) report—told Congress two years ago that evidence for manmade warming is "unequivocal." He claimed "the planet is running a ’fever’ and the prognosis is that it is apt to get much worse." But Trenberth’s "lack of warming at the moment" has been going on at least a decade. (Michael Fumento)
What the science says...
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Trenberth's views are clarified in the paper "An imperative for climate change planning: tracking Earth's global energy". We know the planet is continually heating due to increasing carbon dioxide but that surface temperature sometimes have short term cooling periods. This is due to internal variability and Trenberth was lamenting that our observation systems can't comprehensively track all the energy flow through the climate system. |
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This has been most commonly interpreted (among skeptics) as climate scientists secretly admitting amongst themselves that global warming really has stopped. Is this what Trenberth is saying? If one takes a little time to understand the science that Trenberth is discussing, his meaning becomes clear.
If you read the full email, you learn that Trenberth is actually informing fellow climate scientists about a paper he'd recently published, An imperative for climate change planning: tracking Earth's global energy (Trenberth 2009). The paper discusses the planet's energy budget - how much net energy is flowing into our climate and where it's going. It also discusses the systems we have in place to track energy flow in and out of our climate system.
Trenberth states unequivocally that our planet is continually heating due to increasing carbon dioxide. This energy imbalance was very small 40 years ago but has steadily increased to around 0.9 W/m2 over the 2000 to 2005 period, as observed by satellites. Preliminary satellite data indicates the energy imbalance has continued to increase from 2006 to 2008. The net result is that the planet is continuously accumulating heat. Global warming is still happening.
Next, Trenberth wonders with this ever increasing heat, why doesn't surface temperature continuously rise? The standard answer is "natural variability". But such a general answer doesn't explain the actual physical processes involved. If the planet is accumulating heat, the energy must go somewhere. Is it going into melting ice? Is it being sequestered deep in the ocean? Did the 2008 La Niña rearrange the configuration of ocean heat? Is it all of the above? Trenberth wants answers!
So like an obsessive accountant, Trenberth pores over the energy budget, tallying up the joules accumulating in various parts of the climate. A global energy imbalance of 0.9 W/m2 means the planet is accumulating 145 x 1020 joules per year. The following list gives the amount of energy going into various parts of the climate over the 2004 to 2008 period:
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Land: 2 x 1020 joules per year
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Arctic sea Ice: 1 x 1020 joules per year
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Ice sheets: 1.4 x 1020 joules per year
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Total land ice: between 2 to 3 x 1020 joules per year
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Ocean: between 20 to 95 x 1020 joules per year
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Sun: 16 x 1020 joules per year (eg - the sun has been cooling from 2004 to 2008)
These various contributions total between 45 to 115 x 1020 joules per year. This falls well short of the total 145 x 1020 joules per year (although the error bars do overlap). Trenberth expresses frustration that observation systems are inadequate to track the flow of energy. It's not that global warming has stopped. We know global warming has continued because satellites find an energy imbalance. It's that our observation systems need to be more accurate in tracking the energy flows through our climate and closing the energy budget.
So what may be causing the discrepancy? As the ocean heat data only goes to 900 metre depth, Trenberth suggests that perhaps heat is being sequestered below 900 metres. There is support for this idea in a later paper von Schuckmann 2009. This paper uses Argo buoy data to calculate ocean heat down to 2000 metres depth. From 2003 to 2008, the world's oceans have been accumulating heat at a rate of 0.77 W/m2. This higher trend for ocean heat would bring the total energy build-up more in line with satellite measurements of net energy imbalance.
A subsequent study by Balmaseda, Trenberth, and Källén (2013) determined that over the past decade, approximately 30% of ocean warming has occurred in the deeper layers, below 700 meters. This conclusion goes a long way to resolving the 'missing heat' discrepancy. There is still some discrepancy remaining, which could be due to errors in the satellite measurements, the ocean heat content measurements, or both. But the discrepancy is now significantly smaller, and will be addressed in further detail in a follow-up paper by these scientists.
Summary
So to summarise, Trenberth's email says this:
"The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't."
After reviewing the discussion in Trenberth 2009, it's apparent that what he meant was this:
"Global warming is still happening - our planet is still accumulating heat. But our observation systems aren't able to comprehensively keep track of where all the energy is going. Consequently, we can't definitively explain why surface temperatures have gone down in the last few years. That's a travesty!"
Skeptics use Trenberth's email to characterise climate scientists as secretive and deceptive. However, when one takes the trouble to acquaint oneself with the science, the opposite becomes apparent. Trenberth outlines his views in a clear, open manner, frankly articulating his frustrations at the limitations of observation systems. Trenberth's opinions didn't need to be illegally stolen and leaked onto the internet. They were already publicly available in the peer reviewed literature - and much less open to misinterpretation than a quote-mined email.
Last updated on 24 March 2013 by dana1981. View Archives
One point still puzzles me, though, perhaps because I’m Italian: the word “travesty”. According to my good old Oxford Dictionary it means “a description that intentionally misrepresents the original e.g. burlesque poem etc.” etymology being the Italian verb travestire = disguise. It somehow conveys the impression that the whole thing is a farce, a dress up, an attempt to deceive.
I understand in private informal correspondence one doesn’t care much about wording, but, why didn’t he use pity or shame or bad luck?
John: Terrific post and explanation, by the way. I think this is a nearly perfect example of the way such wholly accurate and innocent statements can be misconstrued by those looking for a good misconstruing.
http://pielkeclimatesci.wordpress.com/2010/04/16/is-there-missing-heat-in-the-climate-system-my-comments-on-this-ncar-press-release/
i find weird your contrasting between science and scientists. But anyway, i find even stranger that a skeptic like Pielke fail to recognize the limitations of our observing system, which is the mantra of the skeptic world including Pielke.
Trenberth's point is quite simple, we can not close the energy budget and this can not be explained just by errors in satellite measurements. The obvious conclusion is that our observing system is not fully adequate to the task. I would have guessed that everyone could agree.
Where in Ternberth 09 does it state that satellites indicate an energy gap? In fact it says '[the ceres data]were adjusted to an estimated imbalance'
Also, what do you think the author meant when he says 'or the warming is not really present?'.
Finally, if the 'climategate' emails were written on public computers, as part of publicly funded studies, how can the author's have any expectation of privacy? And what is the basis of your claim that the emails were stolen?
You say:Where in Ternberth 09 does it state that satellites indicate an energy gap?
Trenberth 2009 states it is the difference between satellite measurements and ocean heat content measurements from ARGO ocean floats. And Trenberth says:
..."Their sum should amount to the sea level from altimetry estimates from satellites, but substantial discrepancies betweentrends of 2 mm/yr were found..."
You say: Also, what do you think the author meant when he says 'or the warming is not really present?'. He is referring to perhaps the satellite observations are incorrect, which is discussed more in the paper on page 24. (See also John's post here too)
You say: ...public computers...how can the author's have any expectation of privacy? And what is the basis of your claim that the emails were stolen?
They are stolen because they were hacked and the Police are investigating.
You can very certainly expect privacy. Even though one might be a public servant, nobody should have ther private correspondences delved into anyone who could misquote it. You may be dealing with sensitive information including defense, patents and communication with industry. Universities and staff have the right to protect their intellectual property. If an official inquiry demands the information stored on public computers then yes of course you would have to disclose the contents but only then.
There are two satellite data-sets discussed in the paper, CERES and GRACE. Which one does Trenberth refer to with this warming quote, in your opinion?
But didn't that happen?
the TOA imbalance come from satellite data. Trenberth has referred to these data several times, for example here.
Thanks for your reply, but referring to data is not claiming it indicates an imbalance.
In fact Ternberth says quite clearly that the CERES data is 'adjusted'.
Seriously, what am I missing here?
"referring to data is not claiming it indicates an imbalance."
What's wrong with referring to data that shows imbalance?
In the section "dataset" they elaborate on this and on the necessary adjustment of the absolute value of the imbalance.
This means that the imbalance is there but it's absolute value is inaccurate.
"The TOA energy imbalance can probably be most accurately determined from climate models and is estimated to be 0.85 ± 0.15 W m−2 by Hansen et al. (2005) and is supported by estimated recent changes in ocean heat content (Willis et al. 2004; Hansen et al. 2005). A comprehensive error analysis of the CERES mean budget (Wielicki et al. 2006) is used in Fasullo and Trenberth (2008a) to guide adjustments of the CERES TOA fluxes so as to match the estimated global imbalance."
So they choose to take the value from Hansen et al. 2005 and adjust the CERES TOA fluxes to match this value.
I'm not sure what this means...but it does not say CERES data indicates an imbalance at all.
Where is this 6.4 W m-2 figure coming from?
FIRST hu?: If I remember from undergrad the 6.4W/m^2 is the difference between the energy Earth receives from the Sun (solar flux 1365W/m^2 minus the CERES global measured flux of reflected sunlight) and that which is emitted back to space as thermal infra-red light (again a flux globally measured by CERES).
SECOND: If I were a climatologist (which I am not) before worrying about the +6.4W/m^2 CERES imbalance I would take a look at the latest peer reviewed engineering analysis of the quality of current CERES data from 2009 G. Matthews, “In-flight Spectral Characterization and Calibration Stability Estimates for the Clouds and the Earth’s Radiant Energy System” Journal of Atmospheric and Oceanic Technology. Vol 26, Issue 9, pp 1685-1716. This explains how CERES solar wavelength calibration suffers un-directly detectable in-flight contaminant degradation and ultimately is based entirely on a reference radiometer on the ground which itself has never been measured and whose mirrors are >13 years old.
[. . .]One point still puzzles me, though, perhaps because I’m Italian: the word “travesty”.
[. . .]
I understand in private informal correspondence one doesn’t care much about wording, but, why didn’t he use pity or shame or bad luck?
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Trenberth was probably thinking of the word tragedy.
I must it is refreshing for a skeptic to give an unequivocal statement of what data would persuade them to change their mind. Well done.
(This is response to comment in another thread
The energy imbalance is as real as the reality of our measurement.
I have never argued that we have not had warming (0.75 degC surface since AD1750). The energy absorbed to produce that temperature increase is in the past.
If surface temperature rise is flattening and heat increase in the oceans is also flattening with better measurement then a reasonable conclusion is that heat imbalance is reducing. The missing heat might stay missing because it was never there.
We are all searching for the truth here. My constant theme is that the AGW case is not as strong as projected by the 'enthusists' precisely because the measurement is deficient. 'Correcting' the CERES imbalance to match the theory and calling that supporting evidence is not science.
Elements of the theory also have wide error bars - eg. clouds and feedbacks.
I am not claiming that there are not bogus arguments on the 'denier' side as well. Of course there are.
However two wrongs don't make a right.
It looks like the missing heat in Earth’s energy budget has been found. Apparently, it’s in the deep ocean. The paper below concludes “the ocean has absorbed considerably more heat than reported by observations, particularly below 700 m”.
Tracking Earth’s energy: From El Niño to global warming
Kevin E. Trenberth and John T. Fasullo
National Center for Atmospheric Research
May 15, 2011
Tracking Earth’s energy: From El Niño to global warming
Basically, they found that 'slowdowns' in upper ocean warming similar to what has been observed recently also show up in many model runs... and when they do the reason is consistently that the heat has been deposited deeper in the oceans. That is suggestive but certainly not definitive.
The "breakfast napkin" sum I did with the 2011 paper shows some 0.13 w/m^2 to 0.28 w/m^2 missing if the ocean retention hypothesis is correct (which it almost certainly is, but it might not be). The median of the "missing" heat has not been observed (yet).
There is a grant proposal being submitted to a few science organizations that seeks to measure the increase (and decrease) in oceanic heat in all four dimensions (i.e., cubic meters over time) to a depth of about 2000 meters. How to do this is a very difficult problem, and it would take an massive amount of money to do properly, and that money will never be provided; but the grant proposal is to perform a short term (minimal ten years) sampling every ten meters. Each buoy would have 200 temperature probes. The problem is that the expense is so great that only a few (30 or so) could be funded, and that is no where near as many as needed: the world's oceans take up a very large volume. The project may never be funded, even for the 30 hoped-for buoy systems.
The bottom line is that humanity will never measure with confident accuracy all of the heat gain and loss going on in the oceans. We can at best measure surface and near-surface temperatures, and thereby infer heat, but the error bars will always be wide.
Don't know where you get your information from, but it is not correct.