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Global Surface Temperature: Going Down the Up Escalator, Part 1

Posted on 5 November 2011 by dana1981

One of the most common misunderstandings amongst climate "skeptics" is the difference between short-term noise and long-term signal.  In fact, "it hasn't warmed since 1998" is ninth on the list of most-used climate myths, and "it's cooling" is fifth.

This myth stems from a lack of understanding of exactly what global warming is.  The term refers to the long-term warming of the global climate, usually measured over a timescale of about 30 years, as defined by the World Meteorological Organization.  This is because global warming is caused by a global energy imbalance - something causing the Earth to retain more heat, such as an increase in solar radiation reaching the surface, or an increased greenhouse effect.

There are also a number of effects which can have a large impact on short-term temperatures, such as oceanic cycles like the El Niño Southern Oscillation or the 11-year solar cycle.  Sometimes these dampen global warming, and sometimes they amplify it.  However, they're called "oscillations" and "cycles" for a reason - they alternate between positive and negative states and don't have long-term effects on the Earth's temperature.

Right now we're in the  midst of a period where most short-term effects are acting in the cooling direction, dampening global warming.  Many climate "skeptics" are trying to capitalize on this dampening, trying to argue that this time global warming has stopped, even though it didn't stop after the global warming "pauses" in 1973 to 1980, 1980 to 1988, 1988 to 1995, 1995 to 2001, or 1998 to 2005 (Figure 1).

skeptics v realists v3

Figure 1: BEST land-only surface temperature data (green) with linear trends applied to the timeframes 1973 to 1980, 1980 to 1988, 1988 to 1995, 1995 to 2001, 1998 to 2005, 2002 to 2010 (blue), and 1973 to 2010 (red).  Hat-tip to Skeptical Science contributor Sphaerica for identifying all of these "cooling trends."

As Figure 1 shows, over the last 37 years one can identify overlapping short windows of time when climate "skeptics" could have argued (and often did, i.e. here and here and here) that global warming had stopped.  And yet over the entire period question containing these six cooling trends, the underlying trend is one of rapid global warming (0.27°C per decade, according to the new Berkeley Earth Surface Temperature [BEST] dataset).  And while the global warming trend spans many decades, the longest cooling trend over this period is 10 years, which proves that each was caused by short-term noise dampening the long-term trend. 

In short, those arguing that global warming has stopped are missing the forest for the trees, focusing on short-term noise while ignoring the long-term global warming signal.  Since the release of the BEST data which confirmed the global warming observed by all other global temperature measurements, climate "skeptics" have been scrambling for a way to continue denying that global warming is a problem, and focusing on the short-term noise has become their preferred go-to excuse.

The Noisy Group

Unfortunately, those making a lot of noise about the noise (and sweeping generalizations that global warming has magically stopped) include several "skeptic" and/or "lukewarmer" climate scientists, who really should know better.  One of these, Judith Curry, is actually a member of the BEST team whose data has been used by climate "skeptics" as "proof" that global warming has stopped.  Unfortunately, Dr. Curry herself fed these myths in a rather dismaying interview:

"There is no scientific basis for saying that warming hasn’t stopped...To say that there is detracts from the credibility of the data, which is very unfortunate...This is “hide the decline” stuff. Our data show the pause, just as the other sets of data do. Muller is hiding the decline"

Predictably, Dr. Curry's comments have been disseminated far and wide by climate "skeptics" who desperately want this myth to be true.

Dr. Roger Pielke Sr. has made similar claims in the comments on Skeptical Science:

"Since 2002, as shown in the lower tropospheric plot and in the upper ocean data, little of that heat has accumulated there. There is not enough melt of sea ice or glaciers to account for it there. "Global warming" has nearly stopped using these two metrics"

Dr. Roy Spencer has taken this argument to the extreme, claiming that based on one cool month in his University of Alabama at Huntsville (UAH) tropospheric temperature dataset, "the troposphere is ignoring your SUV" and that (perhaps sarcastically):

"While any single month’s drop in global temperatures cannot be blamed on climate change, it is still the kind of behavior we expect to see more often in a cooling world"

These climate scientists really should know the difference between short-term noise and long-term signal, and it's a travesty that they're misinforming the public, the media, and policymakers by conflating the two concepts.

The Signal Comes Through Loud and Clear

On the other hand, other scientists who understand statistics are doing an excellent job explaining the difference between signal and noise.  For example, when asked if BEST showed that global warming had stalled over the last decade in response to the interview with Dr. Curry, Dr. Richard Muller (the BEST team lead) said:

“That’s incorrect...I mean, what they have done is an old trick. It’s how to lie with statistics, right? And scientists can’t do that because 10 years from now, they’ll look back on my publications and say, ‘Was he right?’ But a journalist can lie with statistics. They can choose a little piece of the data and prove what they want, carefully cutting out the end. If I wanted to do this, I could demonstrate, for example, with the same data set that from 1980 to 1995 that it’s equally flat. You can find little realms where it’s equally flat. What that tells me is that 15 years is not enough to be able to tell whether it’s warming or not. And so when they take 13 years, and they say based on that they can reach a conclusion based on our data set, I think they’re playing that same game and the fact that we can find that back in 1980, the same effect, when we know it [was] warming simply shows that that method doesn’t work. But no scientist could do that because he’d be discredited for lying with statistics. Newspapers can do that because 10 years from now, nobody will remember that they showed that.”

What the Science Says

The peer-reviewed scientific literature confirms Muller's comments.  For example, Santer et al. (2011):

"Because of the pronounced effect of interannual noise on decadal trends, a multi-model ensemble of anthropogenically-forced simulations displays many 10-year periods with little warming.  A single decade of observational TLT data is therefore inadequate for identifying a slowly evolving anthropogenic warming signal.  Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature."

and Easterling and Wehner (2009):

"Numerous websites, blogs and articles in the media have claimed that the climate is no longer warming, and is now cooling....We show that the climate over the 21st century can and likely will produce periods of a decade or two where the globally averaged surface air temperature shows no trend or even slight cooling in the presence of longer‐term warming."

Not only are these short-term "pauses" just noise in the data, but observations show that they are entirley expected, and predicted by climate models (i.e. see Meehl el al. 2011).

Other Physical Evidence of Continued Warming

It's also important to point out that global temperature measurements aren't our only evidence of the long-term global warming trend.  We've observed many physical indicators of global warming (Figure 2).

warming indicators

 

Figure 2: Physical Indicators of a Warming World

When is Warming Cooling?

When constantly confronted with this myth that global warming stopped in 1998, or 2000, or 2002, or 2005, or [insert year], we wonder why distinguishing between short-term noise and long-term signal is such a difficult concept for climate "skeptics."  They remind us of the Penrose stairs made famous by M.C. Escher - a staircase which people can descend forever and not get any lower.  This paradoxical perception of an impossible construction seems to be how climate "skeptics" view the world, which is undoubtedly why they're willing to risk our future on the hopes that 97% of climate scientists are wrong about climate science.

escher stairs

Part 2 of this post examines the "skeptic" explanation of how these cooling periods can add up to a net warming, and why that explanation is physically incorrect.

Note: this post has been incorporated into the rebuttals to "global warming stopped in [insert year]", and Figure 1 has been added to the SkS Climate Graphics Page

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Comments 51 to 65 out of 65:

  1. Just to add, the statistcal power calculation I tried to discuss with Prof. Pielke Sr is exactly the way in which you would go about assessing the likelihood of the expected trend being swamped by noise. The recipe is basically as follows:

    (i) generate lots of synthetic time-series with the expected trend (say 0.2 deg per decade) and ARMA(1,1) noise similar to the observed data.

    (ii) for each sesies calculate the statistical signiicance of trends over various timescales

    (iii) for each time-scale, calculate the proportion of trends that reach statistical significance

    (iv) plot these proportions as a function of the length of trend and label the y axis "statistical power".

    Statistical power is the probability of rejecting the null hypothesis when it actually is false, so in this case it is the probability that the noise can dominate the AGW signal.

    So that the test is symmetrical, I would suggest that the power should be 95%, so you just need to use a window lengh long enough to have a statistical power of 95% or greater. I expect this is around the 17 year mark. I hope to have a go at this mysel at some point.
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  2. Dikran @50 & 51, I don't have your statistical fire power, but I assumed you could answer Curry's purported question by determining the long term (30 year trend), and then generating all trends of a shorter length (say 10 years) over the interval of the thirty year trend. For 10 year trends, there will be 240 overlapping 10 year trends using monthly data over the 30 year interval. Clearly the average of all the shorter trends will approximate closely to the long term trend.

    With this data, Curries question reduces to, will at least 5% of 10 year trends have a trend at least twice the long term trend, or of opposite sign to the long term trend. If the answer is yes, then short term factors can still swamp the long term trend. If no, then they cannot.

    Now, probably in about 50 years, the answer will be unequivocally "no". At the moment, the answer is very close to "no", but perhaps not. Certainly, however, you will not answer this question by looking at a single cherry picked trend, and especially if you allow yourself the use of dodgy data (April and May of 2010 in the BEST data) to fudge the answer.

    Have I got that right, or have I sawed my way through the branch.
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  3. Tom C#49: Curry's phrasing is confusing at best and quite possibly an attempt to mislead.

    "What is of interest on this timescale is whether natural variability (forced and unforced) can dominate the AGW signal on decadal timescales and produce a ‘pause’ or a ‘stop’."

    With that, she plays a very delicate game of semantics. The words 'pause' and 'stop' confuse the question. Anyone who hears the superficial 'warming stopped' does not hear the following 'because of a relatively large short term variation' and takes away only the carefully crafted message.

    If she agrees that "identifying an AGW signal on this short timescale isn’t useful," then she must agree that saying 'warming stopped' due to a short-term variation is a misrepresentation. All she can claim is that the short term variation is indeed large enough to mask the ongoing rise and make it appear to cool for a few years - something we see clearly demonstrated in the animation in Figure 1 in this post.

    But to imply this short variation is a 'pause' or 'stop' in the long term trend is an overreach. It is akin to Pielke's 'the trend has changed' based on a few years. What of all the past 'pauses' or 'stops'? Did warming stop each time?

    Suppose that your route up a mountain includes a detour down a small valley where you camp for the night. The next morning you continue climbing. Curry and Pielke would describe the overnight as 'climbing has stopped'. That would give the casual observer the incorrect message that you might be on your way down. Such an ambiguous (and false) report could delay a rescue team from reaching your correct position.

    But perhaps that's the reason for these semantic debates; look how much effort has to be spent attempting to set it right. Bravo to tamino for calling her out in front of her own denizens.

    When she’s asked point-blank for the scientific basis of her claims she changes the subject. When she’s shown the error of her ways she refuses to admit it.

    Science by pronouncement: As tamino says "It’s not a crime. It’s a sin."

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  4. Tom, the problem with that approach is that the intervals are not independent (due to the overlap) which would invalidate the comparison (although picking a startpoint ater looking at the data, as Prof. Curry suggests, invalidates the test as well, especially if it coincides with a peak in ENSO!). How much of an effect that would have I couldn't say, but it seems a better approach to use GCM or synthetic data, where you know this isn't going to be an issue (although if you have the synthetic data you could test to see how much difference it makes).
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  5. Out of interest, and using the last 30years of BEST data, the results of my test are:

    30 Year trend: 0.275 degrees C per decade

    Number of 10 year trends less than zero: 2
    Number of 10 year trends greater than twice the thirty year trend: 17

    Total percentage of 10 year trends < 0 or > twice the thirty year trend: 7.9%

    So if my test has any value, the long term trend does not completely dominate short term variations yet, but it's very close.

    Out of interest, the two negative ten year trends where June 1987 to May 1997, and Dec 1987 to Nov 1997. The most recent ten year trend at double the long term trend was from March 1993 February 2003.
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  6. Here is another way to look at long vs. short:


    -- source

    The red is BEST with a 12 month mean; green is the linear trend. Then use the detrend operator to remove that, yielding the blue curve. Sure looks like the blue oscillates around 0; but if you wanted to play the 'eyecrometer pick-a-trend' game, are the peaks at the tail end of the blue curve trending up?

    Or does 'warming stop' every 4 years or so?
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  7. muoncounter @53, I am in wholehearted agreement with everything you say. IMO Curry has behaved despicably throughout. Her new wording, which certainly lacks clarity, is not what she was originally maintaining. It is, however, important to know she is not saying the same thing, and to criticize he as though she where saying the same thing.

    Regardless, however, even for what she is now saying, she is not justified in cherry picking start dates. At a minimum she should have been doing what I just did in 55. Even that, Dikran now advises me, is not a proper test. But it would certainly be better than cherry picking a single year, and as can be seen the results do not encourage her pretense.

    This whole storm started because Curry insisted that a single cherry picked data set of less than 10 years using dodgy end data showed us something significant. Well, to find a 10 year interval in the BEST data with a negative 10 year trend, you need to go back 14 years and pick one of two out of 240 possible ten year trends. That's quite some cherry pick she indulged in.
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  8. Tom@57 Your method is way better than Curry's approach, a single time period which is so short that the test for the trend doesn't have useful statistical power and has a cherry picked startpoint tells you precisely nothing about the trends. It says quite a lot about Prof. Curry's grasp of statistics, as an experienced scientist she should be able to formulate her hypotheses uambiguously and rigorously test them before promulgating them.
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  9. Tom#57: "you need to go back 14 years and pick one of two out of 240 possible ten year trends."

    I think that is an excellent and very compelling point.

    If this (2 out of 240!) was the strength of the warming argument, the skeptics and pseudo-skeptics would be jumping up and down crying 'Foul!' for good reason. But this is the strength of the pseudo-skeptic argument, so it must be ok.
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  10. Some interesting comments here. My main concern is the same as muon @53 - that Curry has repeatedly used the phrasing "warming has stopped," which implies a termination. "Paused'", while not a good descriptor, at least implies that it will soon resume. Pielke used the same phrasing. When dealing with global warming, about which a large group of people are trying to convince the public that global warming really has stopped, or at least is nothing to worry about, such inaccurate and cavalier language is unwise and damaging. DNFTD.
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  11. I think I've realized what bothers me about the "skeptics" version of "the warming has stopped". I think it is a variation of the Fallacy of the Undistributed Middle. The question I ask is "what warming?"

    a) the warming due to human-induced increases in CO2?

    b) the warming due to a) plus all other factors that affect global temperatures?

    The temperature records shows b). Attribution studies attempt to tease out a) from b). Theory tells us that b) will not rise continuously at a steady rate: it will have fluctuations imposed on the long-term trend that is caused by a).

    Now here's the rub: the "skeptics" look at variations in b) and make statements like "the warming has stopped", but what they are trying to imply (whether they believe it or not, or whether they are just employing FUD), is that noting a change in b) means that a) has stopped. The word "warming" does not mean the same thing in a) and b) - that's the undistributed middle in the logical fallacy.

    To make an analogy, let's say we have a bathtub full of water. At one end, we have a small heater. At the other end, we measure temperature. Periodically, someone stirs up the tub. Over time, we see the temperature rise slowly, but it doesn't rise evenly because the mixing isn't uniform. Let's say someone periodically adds some ice at the thermometer end - that causes periodic drops in observed temperature.

    We know that the heater at the far end is still adding energy slowly warming the bath, but the "skeptics" want us to believe that the occasional drop in temperature (or decrease in the heating rate) at one end means that the heater at the other end has stopped - or even never existed at all.

    There is also (yet another) inconsistency in the skeptic position here: they often argue the strawman that climatologists ignore other factors when attributing the global temperature rise to CO2. Yet that is exactly what the "skeptics" are doing when they pretend that short-term fluctuations are evidence against the current scientific understanding of global temperature and the effects of CO2.
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  12. Dana1981 - great post! I think it would be even more powerful if the animation ended showing the real trend AND the denier version. The visual contrast, at the same time, would be stunning. (Of course it would be so fun it would need a way to play it again).

    I would love to be able to link to that when I am whopping the deniers on Politico.
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  13. It seems that Camburn ran out of arguments as he completely vanished after having been sooo disproven it hurts!

    Classic skeptic behavior: misinform and vanish. Damage done!
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  14. @Dikran 50-

    Brilliant...finally a distillation of what it's really all about.... natural variation/noise swamping the AGW signal vs the AGW signal disappearing. Making that explicit is really important...because I think Curry et al are blurring that distinction, perhaps on purpose to "feed the uncertainty monster".

    I can see a cartoon based on "little shop of horrors"...with Audrey II being labled "The Uncertainty Monster"...and Prof. Curry scurring around in response to its demands "Feeeeeeeeeed me!"
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  15. Hansen has singled out ocean heat content measurements as the most important indicator of a "warming world" for many years. Now that precise measurements look like they are becoming available, he is emphatically calling attention to them.

    Since 2005 he has been describing calculations primarily based on measured ocean heat content in his public statements as a “smoking gun”. Now the term, i.e. “smoking gun”, is in his latest paper in press.

    He is becoming increasingly confident in analyses of data coming from the recently deployed Argo floats:

    “The strong positive energy imbalance during the solar minimum, and the consistency of the planet’s energy imbalance with expectations based on estimated human-made climate forcing, together constitute a smoking gun, a fundamental verification that human-made climate forcing is the dominant forcing driving global climate change.”

    This is the data he is using:



    (From von Shuckmann and Le Traon 2011, “How well can we derive Global Ocean Indicators from Argo data?”)

    To illustrate how “noisy” the previously available ocean heat storage data is compared to this new Argo data, Hansen provided this chart. The solid red line is his calculation based on the data from the von Schuckmann chart above, and the dotted red line is calculation based on data from a previous von Shuckmann et. al. effort. Both are Argo analyses:



    The ocean is where the heat is. Mere sloshing around of a tiny bit of the heat in the ocean, i.e. ENSO, can show up as a cooling trend in the global average surface temperature chart. Debate about whether the planetary system could possibly be cooling should be done using terms that make it clear that the global average surface temperature chart isn't a measure of whether the planet is cooling or not, or whether global warming is occurring or not.
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  16. I don't agree with Muller that no one cares what journalsts said 10 years ago. What about the global cooling prediction in the 1970s that was more in the media than the scientific literature?
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  17. Andrew Revkin just featured The Escalator at the NY Times Dot Earth blog.
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  18. There's an (anomalous?) spike down below -1 at 2010 in the animated graphic. It appears only in the final "skeptic" frames, and disappears in the realist frame. Can this be corrected please? I'd like to use the image in my talks to Probus Clubs. Thanks.
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  19. jondoig - that spike is left there intentionally. When it was first released, the BEST dataset contained two incomplete points in the final two months, only containing data from Antarctic stations, as I recalled. However, the 'skeptics' retained those incomplete and clearly anomalous data points in order to argue that BEST proved the planet was cooling. If you remove those data points, the recent short-term trend is no longer negative.

    Thus I left those data points in there because as the graphic title notes, that is how 'skeptics' viewed the data. However, realists knew that the final two points were incomplete and removed them, hence I removed them from the realist frame.
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  20. What intrigues me about Levitus et al:

    Levitus etal show a dramatic chart of escalating oceanic heat content.

    But water has a huge heat holding capacity. If converted to the units measured (heat increment, in degrees centigrade) we find the top 2000 meters of the entire world’s oceans has risen 0.09 degrees C over a period of 55 years.

    0.09 degrees C over 55 years?

    Can they really measure the temperature of the whole world's ocean to that degree of accuracy even now, with the Argo floats?

    And could they measure to that level of accuracy 55 years ago, with buckets and ropes?
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  21. Markx, the short answer is yes; statistically reliable, useful and significant measurements can be assembled from the plethora of data sources available to oceanographers.

    A longer answer-- typical and one of many describing specific methods-- can be found here:

    Improved Analyses of Changes and Uncertainties in Sea Surface Temperature Measured In Situ since the Mid-Nineteenth Century: The HadSST2 Dataset

    As always, follow references to drill into the whole story.

    These people have really powerful senses of curiosity and are extremely stubborn in their pursuit. Same deal as with many other amazing human endeavors.
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  22. Markx - what makes you think the extra heat, which has accumulated in the top 2000 metres of ocean, has been evenly distributed?

    The flaw in your argument is rather easy to spot, but I'd be genuinely interested in your justification for making this claim.

    And on the buckets & ropes comment, maybe you're thinking of something else. How do you measure ocean temperature down hundreds of metres with a bucket?
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  23. Markx - you might ask the same question of the surface temperature record. Surely we arent measuring temperatures back a century to 0.01C? No, the instuments are not. However, the precision of the average is not the same as the precision of an individual measurement. This is fundamental statistics.

    For detailed discussion about how accurately can you measure anything from Argo, see Von Schuckmann and Le Traen 2011 .
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  24. Rob Painting at 19:10 PM on 2 November, 2012
    "...measure ocean temperature down hundreds of meters..."

    Yes, with a mercury thermometer, but marked in 1/10th degrees.

    Until about 2004, there were not so many Argo measures being taken below 700 meters. The Argo project only really starting in earnest in 2000.

    It seems to be quite test of the power of the statistical analyses to take this back to 1955.

    Granted, not evenly distributed: Levitus etal 2010 showed a 0.18 degree C rise in the Zero to 700 meter depth range world wide over 55 years, as well as the aforementioned 0.09 degrees C rise over the whole 2000 meter depth over 55 years.
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  25. I worry at the statistically calculated precision over a 55 year period from data which itself has required corrections.

    It seems the Argo floats are not always precision instruments.

    From NASA – (Titled “Correcting Ocean Cooling”. by Rebecca Lindsey November 5, 2008
    http://earthobservatory.nasa.gov/Features/OceanCooling/page1.php

    “…But when he factored the too-warm XBT measurements into his ocean warming time series, the last of the ocean cooling went away. Later, Willis teamed up with Susan Wijffels of Australia’s Commonwealth Scientific and Industrial Organization (CSIRO) and other ocean scientists to diagnose the XBT problems in detail and come up with a way to correct them. “So the new Argo data were too cold, and the older XBT data were too warm, and together, they made it seem like the ocean had cooled,” says Willis. …”
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  26. Markx, you're probably not very worried, or you'd dig into the literature and learn how the temperature record is assembled. If you're really worried it would be better to take a hint, stop voicing your fears and go help yourself. Clearly you know how to do that.

    But here's the rub if you've got other issues with the matter of ocean warming: if you question the measured amount of warming of the ocean then you also have to come up with an alternate explanation for thermosteric SLR. Tough cookie to crack: if the average km3 of the ocean is expanding in volume, how does it accomplish that without becoming warmer?

    As you begin to replace thermosteric SLR with a novel hypothesis you'll be entering the region of "here be dragons." Tread carefully.
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  27. Markx - Yes, with a mercury thermometer.

    Reversing thermometers, but it's good to see you've moved on from the ropes and buckets claim. I note you never attempted any explanation as to why you thought ropes and buckets were used to measure subsurface ocean heat. Is that a myth circulating on contrarian blogs?

    "It seems to be quite test of the power of the statistical analyses to take this back to 1955"

    The uncertainty of the analysis is shown in vertical red bars (0-2000mtrs) & grey shaded areas (700-2000m) in this figure from Levitus (2012):



    "I worry at the statistically calculated precision over a 55 year period from data which itself has required corrections"

    Virtually all datasets require corrections. Until such time as humans invent a perfect measuring instrument, it's something we have to live with.

    The issues with some of the ARGO floats is unlikely to side with the wishful thinking of contrarians I'm afraid. The faulty floats have a pressure sensor issue which underestimates the actual depth that they are at. This means they are taking a temperature reading colder than is actually the case, introducing a cool bias into the dataset.

    This issue is still being addressed, and no doubt other problems will crop up, but this is no different to any other climate-related dataset.

    I do note, however, that many contrarians, such as Roger Pielke Snr, thought ARGO was the greatest thing since sliced bread when it indicated the oceans were cooling. But now that ARGO confirms the long-term ocean warming trend, contrarians are falling over themselves trying to find excuses not to accept the evidence.
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  28. I note that the graphical representation of the data from Levitus 2012 shows approximately 50% data coverage down to 2000 m up to the end of the time series shown.

    I suspect, given additional papers discussed in this Skeptical Science post, that improving the coverage would not favour the claim that the oceans are cooling.
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  29. Markx says ""I worry at the statistically calculated precision over a 55 year period from data which itself has required corrections."

    Looking a the loss of Arctic Sea ice, loss of permafrost, extreme weather events, rising sea levels, extreme storm surges, I am of the opinion that there are other things to "worry" about.
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  30. Markx, at the moment, you are making a claim from Personal Incredulity. Perhaps it would be best to start with the actual papers that make the claims and fault their logic instead? But as Doug points out, the claim passes the "sniff test" - the OHC increase is consistent with thermosteric sea level rise.
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  31. Rob Painting at 05:53 AM on 4 November, 2012

    "....Virtually all datasets require corrections. Until such time as humans invent a perfect measuring instrument, it's something we have to live with..."

    Agreed. It was interesting to note that the errors in the Argo data were detected due to mismatching with Ceres TOA data. Of course, Ceres data is also adjusted, to match modeled TOA expectations.

    I respect and admire the detail these scientists go to to monitor, analyze and correct such data. But I cannot help but wonder about corrections piled on adjustments, and I appreciate the chance to discuss this.

    Loeb etal 2009 ‘Toward Optimal Closure of the Earth’s Top-of-Atmosphere Radiation Budget’ J. Climate, 22, 748–766

    This study provides a detailed error analysis of TOA fluxes based on the latest generation of Clouds and the Earth’s Radiant Energy System (CERES) gridded monthly mean data products [the monthly TOA/surface averages geostationary (SRBAVG-GEO)] and uses an objective constrainment algorithm to adjust SW and LW TOA fluxes within their range of uncertainty to remove the inconsistency between average global net TOA flux and heat storage in the earth–atmosphere system.
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  32. scaddenp at 14:42 PM on 4 November, 2012

    "...the claim passes the "sniff test" - the OHC increase is consistent with thermosteric sea level rise...."

    In addition to above posts, satellite TSL rise itself is not matching OHC as calculated from known measurements.

    But is there a really tight agreement between calculated and TSL, measured OHC and TOA?

    It seems to me all require adjustments, partially based on each-other.

    GEOPHYSICAL RESEARCH LETTERS, VOL. 32, L12602, 4 PP., 2005
    doi:10.1029/2005GL023112 Thermosteric sea level rise, 1955–2003 Antonov Levitus Boyer

    For the 1955–2003 period, the thermal expansion of the 0–700 m layer of the World Ocean contributed approximately 0.33 mm/year to global sea level rise. About half of this thermosteric trend is due to warming of the Atlantic Ocean. Approximately one third of the total thermosteric rise is due to the warming of the Pacific Ocean. For the period of available TOPEX/Poseidon (T/P) satellite altimetry data (1993–2003), the linear trend of thermosteric sea level (0–700 m) is 1.23 mm/year, 60% of which is due to the trends in the Pacific Ocean. For the 0–3000 m layer of the entire World Ocean, the linear trend of thermosteric sea level is 0.40 mm/year for 1955–1959 through 1994–1998.
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  33. ...interesting to note that the errors in the Argo data were detected due to mismatching with Ceres TOA data.

    I'd be interested in seeing a reference for that. Pointer?
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  34. Markx, you seem to be going on an adjustment binge.

    Perhaps before questioning yet more adjustments you should describe in detail the basis of your doubts, keeping in mind that "I doubt it" is not an argument?
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  35. Current satellite data (Icesat, Grace, Jason..) would seem to suffer from some imprecision (1+ mm/yr), hence the proposed GRASP mission (it is marvelous to see the detail that goes into these projects)

    http://ilrs.gsfc.nasa.gov/docs/GRASP_COSPAR_paper.pdf


    Thus, we assess that current state of the art reference frame errors are at roughly the mm/yr level, making observation of global signals of this size very difficult to detect and interpret. This level of error contaminates climatological data records, such as measurements of sea level height from altimetry missions, and was appropriately recognized as a limiting error source by the NRC Decadal Report and by GGOS.


    This is all heading in the right directions, but it seems to me at this stage it still leaves us with a cycle of interdependent adjusted data: OHC/TSL/TOA.
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  36. Whoops, belay that request. Here's what Markx is talking about:

    Global climate change results from a small yet persistent imbalance between the amount of sunlight absorbed by Earth and the thermal radiation emitted back to space1. An apparent inconsistency has been diagnosed between interannual variations in the net radiation imbalance inferred from satellite measurements and upper-ocean heating rate from in situ measurements, and this inconsistency has been interpreted as ‘missing energy’ in the system2. Here we present a revised analysis of net radiation at the top of the atmosphere from satellite data, and we estimate ocean heat content, based on three independent sources. We find that the difference between the heat balance at the top of the atmosphere and upper-ocean heat content change is not statistically significant when accounting for observational uncertainties in ocean measurements3, given transitions in instrumentation and sampling. Furthermore, variability in Earth’s energy imbalance relating to El Niño-Southern Oscillation is found to be consistent within observational uncertainties among the satellite measurements, a reanalysis model simulation and one of the ocean heat content records. We combine satellite data with ocean measurements to depths of 1,800 m, and show that between January 2001 and December 2010, Earth has been steadily accumulating energy at a rate of 0.50±0.43 Wm−2 (uncertainties at the 90% confidence level). We conclude that energy storage is continuing to increase in the sub-surface ocean.


    Observed changes in top-of-the-atmosphere radiation and upper-ocean heating consistent within uncertainty
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  37. And here's the relevant passage, which does not reflect Markx's claim about Argo errors being detected by comparison with CERES data. Markx, did you remember reading such a thing yourself, or is it a rumor you've heard?

    To provide a more observation-based representation of changes in net TOA flux during the past decade, the CERES net TOA radiation record is anchored to an estimated Earth heat uptake for July2005June 2010 of 0:580:38 Wm2, by combining the Pacific Marine Environmental Laboratory/Jet Propulsion Laboratory/Joint In-stitute for Marine and Atmospheric Research (PMEL/JPL/JIMAR;ref. 14; see Methods) Argo-only estimate from 0 to 1,800 m with estimates of smaller heat uptake terms from warming of the deep ocean, land and atmosphere, as well as melting ice. Argo alone samples consistently, persistently, globally, and to a greater depth than previous upper-ocean measurement programs. A comparison of
    year-to-year changes in CERES net TOA flux during the past decade with the PMEL/JPL/JIMAR estimates of 0700 m and 01,800 m year-to-year ocean heating rates (Fig. 3a) reveals that although thesatellite and ocean in situ interannual variability agree to within observational uncertainty, the error bars and year-to-year variations for upper-ocean heating rates are large earlier in the decade, when much of the ocean in situ data were from XBT measurements,which have poorer sampling than Argo and require large uncertain bias corrections that Argo does not. Consistency between satellite
    net TOA flux and upper-ocean heating rate variability improves after 2004, when the Argo network provides near-global coverage. Importantly, the CERES net TOA flux observations do not show a sharp decline during the XBT to Argo transition around 20022005. For 20042010, the year-to-year changes in net TOA flux and the PMEL/JPL/JIMAR ocean heating rate track one another with a correlation coefficient of 0.46. During the same period, the correlation coefficients between CERES net TOA flux and 0700 m ocean heating rates from both National Oceanic Data Center (NODC) and Hadley is 0.05. Although we cannot confidently claim that one ocean heat content estimate is preferable to another, the better
    agreement between the CERES and PMEL/JPL/JIMAR year-to-year changes after 2004 is encouraging. Combining the stable, decadal-length record of changes in net radiation from CERES with the 01,800 m Argo OHCA record and other minor storage terms, we compute Earth's energy imbalance for the period from January 2001December 2010 to be 0:500:43 Wm2
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  38. Markx, as your other claim about Argo and CERES proved incorrect, what are we to make of your claim that ...Ceres data is also adjusted, to match modeled TOA expectations.

    Are you remembering that incorrectly, or is that a rumor you've heard? Or is it real? How about a reference?
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  39. doug_bostrom at 16:05 PM on 5 November, 2012

    "...I'd be interested in seeing a reference for that. Pointer? .."

    Hi Doug; for the article mentioned in a previous post.

    From NASA – (Titled “Correcting Ocean Cooling”. by Rebecca Lindsey November 5, 2008 http://earthobservatory.nasa.gov/Features/OceanCooling/page1.php

    “Our team has been involved for many years in constructing time series of net flux from satellite data, going back to the 1980s,” says Wong. The observations started with a satellite mission called the Earth Radiation Budget Experiment and today are being made with Clouds and the Earth’s Radiant Energy System (CERES) sensors on NASA’s Terra and Aqua satellites....

    ....From 1993 to 2003, measurements of heat storage in the oceans agreed with satellite observations of net flux. After 2003, however, surface observations suggested that the ocean was losing heat, while satellite measurements of net flux showed the Earth was still slowly gaining energy. This mismatch was a hint that there might be a problem with one of the data sets.


    I'm not on any mission at all. Just asking sensible questions.

    We have a very small temperature increment of great precision, all 'proven' or at least 'confirmed' by interdependent adjusted measurements.

    I have no doubt re the skill and integrity of the scientists involved, but have some doubts re the risks of using pyramided data adjustments and calibrations in proving a 'fact'.

    I trust you can assure me it is all as clear and precise as you report it to be.
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  40. That's stale, Markx. You need to stay up to speed lest you mislead people.
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  41. doug_bostrom at 16:46 PM on 5 November, 2012
    ".... CERES data is also adjusted, to match modeled TOA expectations....How about a reference? ..."

    Hi Doug, provided in #81, but here it is again (added detail):

    Loeb etal 2009 ‘Toward Optimal Closure of the Earth’s Top-of-Atmosphere Radiation Budget’ J. Climate, 22, 748–766

    This study provides a detailed error analysis of TOA fluxes based on the latest generation of Clouds and the Earth’s Radiant Energy System (CERES) gridded monthly mean data products [the monthly TOA/surface averages geostationary (SRBAVG-GEO)] and uses an objective constrainment algorithm to adjust SW and LW TOA fluxes within their range of uncertainty to remove the inconsistency between average global net TOA flux and heat storage in the earth–atmosphere system....

    ...The 5-yr global mean CERES net flux from the standard CERES product is 6.5 W m−2, much larger than the best estimate of 0.85 W m−2 based on observed ocean heat content data and model simulations. The major sources of uncertainty in the CERES estimate are from instrument calibration (4.2 W m−2) and the assumed value for total solar irradiance (1 W m−2).
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  42. Excellent sound bytes can be clipped from abstracts, Markx, but it helps to read the entire paper. When you do that you'll find there's a physical basis for adjustments. It's not just a matter of guessing. For example:

    Another positive bias is associated with how the global average solar irradiance is calculated. It is common practice to assume a spherical earth when averaging TOA insolation over the earth’s surface. This gives the well-known So/4 expression for mean solar irradiance, where So is the instantaneous solar irradiance at the TOA. When a more careful calculation is made by assuming the earth is an oblate spheroid instead of a sphere, and the annual cycle in the earth’s declination angle and the earth–sun distance are taken into account, the division factor becomes 4.0034 instead of 4. The spherical earth assumption causes a 1 0.29 W m 22 bias in net TOA flux. Similarly, assuming a spherical earth in determining the global average SW and LW TOA fluxes (by using a latitude weighting in geocentric instead of geodedic coordinates) results in 10.18 and 20.05 W m 22 biases, respectively.


    And:

    After the release of SRBAVG-GEO edition 2D, an error was discovered in the computation of the declination angle and earth–sun distance factor. The angle and factor were computed at 0000 UTC instead of 1200 UTC, which is appropriate for computing the solar incoming in local time. This has no effect on the annual mean insolation but significantly affects the monthly zonal solar incoming fluxes near the poles. This error iscorrected in the final adjusted TOA fluxes and will also be rectified in the next SRBAVG version (edition 3). Adjustments to total solar irradiance associated with the spherical earth assumption are applied zonally to improve the accuracy of incoming solar radiation at each latitude. While these adjustments are applied at the zonal level, the globally averaged correction is the
    same as in Table 2. Similarly, adjustments in SW TOA fluxes due to near-terminator flux biases are also applied zonally without modifying the global mean. Separate adjustments are made for clear and all-sky TOA fluxes.


    And no, the objective of the paper is not to have CERES data chase model output. Don't be insulting.
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  43. doug_bostrom at 17:25 PM on 5 November, 2012
    ".... the objective of the paper is not to have CERES data chase model output...."

    Hi Doug.

    Forgive me if I misinterpret you here:

    Where did the knowledge of the TOA flux come from? Are you saying that knowledge of the TOA flux was innate, and this was only about ironing out the kinks in the satellite measurements?

    And now we have finally got the satellite measures of TOA spot on? They match "the actual"?

    Utilizing calculated net heat storage of the earth, and estimated or known (from where?) TOA fluxes, it seems we can adjust our satellite measurements. And using our (new-found?) knowledge of the TOA flux we can confirm that it (now) matches the OHC data. (Itself measured to a precision of 3 decimal places over 55 years).
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  44. You apparently still have not read the paper, Markx, or you would not continue missing the entire point of the authors by saying such things as "Are you saying that knowledge of the TOA flux was innate, this was only about ironing out the kinks in the satellite measurements?" which clearly indicates you've got the entire concept of the paper neatly backward.

    The objective of the authors had nothing to do with improving CERES data. They necessarily explain the evolution of improvements in CERES data by the experiment operators but that's not the point of the paper.

    Looking beyond your problem with understanding the paper you brought up, what I find surprising is your metaphorical condemnation of calibration via your suspicions over the refinement of CERES data (and apparently any other data you find inconvenient). Apparently you're more comfortable with the idea that instrumentation should be manufactured and deployed in a state of nature, reading just as it did when first assembled regardless of whether the dial pointing to "accurate" was put on its axle pointing reciprocal to its proper direction.
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  45. Rereading Markx's last comment I'm moved to amend my last remark (retracting "nothing to do with" and "not the point" 8-P ). It's true that Loeb et al. were seeking to improve CERES results by systematically eliminating errors, using Hansen et al 2005 0.85W/m2 as a benchmark. I did take Markx's first remark on the matter to mean that CERES data is essentially a pure derivative of model output, which it is not. As many of us are probably painfully aware, Hansen's paper reports prediction and observation of the same imbalance.

    Readers might want to take a look at table 2 of Loeb and decide what the dominant source of error is going to be. Personally I'll put my money on OHC measurements being the least of the problems, way less than other issues w/CERES at this level of precision.

    I suppose I've already developed an observational bias based on Markx's Argo error. Too twitchy. :-)
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  46. Doug, there's an SkS post about Loeb (2012) here: Search For 'Missing Heat' Confirms More Global Warming 'In The Pipeline'

    The Levitus methodology, upon which Levitus (2012) & Nuccitelli (2012) are based, actually shows the smallest warming rate over 2004-2008, for the upper 700 metres of global ocean. This is largely down to differences in how to handle sparse sampling in the datasets.

    Contrary to Markx's insinuations, uncertainty is like a dagger - it cuts both ways.
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  47. "But is there a really tight agreement between calculated and TSL, measured OHC and TOA? "

    So measurement of sea level is dependent on heat measurements?? Sea level has the interlinked tide gauge and satellite measurements.

    There are many problems in determining heat imbalance from satellite measurements. Argo is quite definitely the best instrument for that but it's short term data. On the other hand, the problems is closing the heat balance would point to MORE heat being stored in the ocean to close with the sea level curve not less.
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  48. scaddenp at 19:49 PM on 5 November, 2012

    "...So measurement of sea level is dependent on heat measurements?? Sea level has the interlinked tide gauge and satellite measurements..."

    No, but all are interlinked. Each is used to justify the value obtained for the other. As is pointed out, that does not mean any of them are incorrect. And, on the other hand it does not mean that all, or any of them are entirely correct.

    We are really still in the very early stages of data collection here, with ocean temperature data being collected in detail and depth only since 2000, and satellite data for both TOA radiation flux and sea level rise needing better technology and better data.

    This is a perfectly legitimate topic for discussion, and I am surprised you find it heretical;

    Topic: Just how precisely measured are all these parameters?
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  49. Uncertainty is a topic for legitimate discussion. We've seen little of that from you so far. You started with ropes and buckets, and appear to have dredged google in order to throw up research which, you believe, casts doubt on the very obvious warming of the planet.

    Uncertainty is discussed in the literature, and observationally-based studies do quantify this. It is no great secret. Now if you want to start quantifying this yourself, and/or actually engage in meaningful discussion, then do so. Needless repetition of memes or myths constitutes sloganeering, and may result in future comments being snipped accordingly.

    Do note, however, that Earth's observed energy imbalance is a logical consequence of the increased Greenhouse Effect. Reduce the rate of loss of heat to space, and the Earth must warm to eventually return to equilibrium. So there is a very obvious physics-based foundation which underpins the observations.
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  50. Looks like my post got lost (not too sure of my maths below, but it's be ballpark correct I think):

    doug_bostrom at 19:29 PM on 5 November, 2012

    "..Markx's Argo error. ..." I didn't think I was in error there, I simply asked a question.

    The 0 to 700 meter level of the world's oceans have risen 0.18 degrees C in 55 years (early measurements were taken from ships decks using a reversing mercury thermometer calibrated in 10ths of degrees C, by a line ... thanks Rob)

    And the total 0 to 2000 metre range of the world's oceans has been measured to have risen 0.09 degrees C over 55 years...

    So therefore the 701 to 2000 meter ocean depth must have risen a measured 0.00415 degrees C in 55 years.

    Is my maths correct?
    0 0
    Moderator Response: (Rob P) - No need to even bother checking your math. You are simply repeating a fallacy, and one that was corrected by SkS commenters previously -see comments 72 & 73.

    The precision of the measurements cannot not be determined by taking the warming of the whole 0-2000 meter layer and dividing that into the ocean volume (assuming that is what you've done).

    Following on from Doug Bostrom's comment, here's a simple analogy for readers benefit:

    A University experiment is carried out to determine whether staff/students are gaining or losing weight over time. Regular weighing is carried out and at the end of the experiment it is found that all involved have gained a total of x kilos.

    "Whoa! Wait a moment!" says Markx "How can we be sure? When I take x (the total weight gained) and divide it by the number of people weighed, the number is 0.000x. There is absolutely no way the scales have that sort of precision. How can we be sure that anyone gained any weight at all?"

    Thus the illogicality of your thinking is illustrated such that even the non-technically-minded can understand.

    Also please note that constantly repeating a myth/fallacy is deemed to be sloganeering. This therefore constitutes the first of 3 warnings. Please familiarize yourself with comments policy.

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