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  1. Hmm… so does it really matter?

    Comment by Magnus Westerstrand — 6 May 2009 @ 3:02 AM

  2. Hi Rasmus

    There is inconsistency between ACRIM reconstruction during the 22 minimum and the GCR, OK, but also with radio flux and SSN.
    It is not the case for PMOD.
    When we look at the to-day situation at the beginning of 24 cycle, the correlation between SSN, PMOD TSI, and radio flux is good, so, why should’nt it be during 22 minimum?

    Comment by pascal — 6 May 2009 @ 3:52 AM

  3. The link to supplementary materials appears now to be working. It contains original figure files, and a probably more interesting statement from Douglas Hoyt.

    Best Regards

    [Response: Link here. - gavin]

    Comment by Giovanni Pellegrini — 6 May 2009 @ 4:14 AM

  4. If two papers come to different conclusions then each should find out what is wrong in the other.

    After that, pass these comments back. See what changes come up. If they still disagree and point different directions, then there is no conclusion.

    Neither are right. The long term trend is officially a known unknown.

    Comment by Mark — 6 May 2009 @ 5:13 AM

  5. Is it significant?

    From the SW09 abstract:

    Both ‘mixed’ composites demonstrate a significant TSI increase of 0.033 %/decade between the solar activity minima of 1986 and 1996, comparable to the 0.037 % found in the ACRIM composite.

    The IPCC AR4, 2.7.1.2.2:

    In terms of plausible physical understanding, the most
    likely secular increase in total irradiance from the Maunder
    Minimum to current cycle minima is 0.04% (an irradiance
    increase of roughly 0.5 W m^-2 in 1,365 W m^-2), corresponding
    to an RF of +0.1 W m–2. (…) Since the 11-year cycle amplitude has increased from the Maunder Minimum to the present, the total irradiance increase to the present-day cycle mean is 0.08%.

    Does this mean the decadal increase claimed by SW09 is on the same order as the whole TSI increase since the Maunder minimum? Or am I missing something?

    Comment by CM — 6 May 2009 @ 8:13 AM

  6. It might be helpful to state what the two different trends imply for solar forcing over the past few decades or so. For the lay audience like myself, who might not know that. In other words, how significant is the discrepancy for interpreting the current warming?

    Your reference to SkepticalScientist told me what I wanted to know. They say: “Regardless of which dataset you use, the trend is so slight, solar variations can at most have contributed only a fraction of the current global warming.” Might be worth having that said here (if you agree), to frame the issue a bit more.

    Comment by Christopher Hogan — 6 May 2009 @ 8:27 AM

  7. CM #5 : According to the authors, it should indeed be significant (provided they’re right ;-) ). They conclude with:

    “This finding has evident repercussions for climate change and solar physics. Increasing TSI between 1980 and 2000 could have contributed significantly to global warming during the last three decades [Scafetta and West, 2007, 2008]. Current climate models [Intergovernmental Panel on Climate Change, 2007] have assumed that the TSI did not vary significantly during the last 30 years and have therefore underestimated the solar contribution and overestimated the anthropogenic contribution to global warming.”

    Comment by manu — 6 May 2009 @ 11:03 AM

  8. My post on PMOD vs ACRIM is the first of two; more relevant to the comparison of those two reconstructions is the second post, here.

    Comment by tamino — 6 May 2009 @ 12:42 PM

  9. Seems to me this focus only on TSI and the slight changes from minima to
    maxima and over the decades (and the slight impact this may have on climate)
    misses the point.

    What I want to understand, and this is not something I’ve seen covered very
    well in any paper I’ve seen, is how the distribution of the spectrum of
    wavelength of radiation from the sun has changed over time. Both from solar max
    to min and from one cycle to the next – and how this spectrum is changing in
    the current minimum, which is certainly unusual at least in modern terms.

    Gavin – I believe you co-authored a paper stating that the UV spectrum during
    solar minimum decreases by (at least) 6% during minimum. How does this affect global
    cloud cover, assuming Cosmic Rays are not an important factor. What about other
    wavelengths? How does this change in the spectrum affect absorption and
    reflectivity in the atmosphere and in the groundcover/oceans?

    There have been other studies done that show that cloudcover (and the earth’s
    albedo) increase during solar minimum. What is the mechanism that causes this
    and how would this be affected by a prolonged solar minimum which is certainly
    possible given the unusual things the sun is doing now?

    Comment by tjlyerly — 6 May 2009 @ 12:52 PM

  10. Now let me get this straight (correct me if I’m wrong):
    – The sun goes thru cycles between solar minima and solar maxima (activies, like flares and sunspots) & with the solar minima we’d have less TSI, and with the maxima we’d have more TSI.
    – The solar maxima would warm the earth a bit (or is it the TSI that’s warming it a bit?), and the solar minima would cool the earth a bit.
    – We apparently are in a solar minima right now, so ergo the earth should be cooling, all other things being equal, which they are not.
    – AGW denialists think somehow that being in a solar minima disproves AGW, even tho we’re not (from what I understand) cooling down as much as would be expected, and are actually warming up.
    – AGW denialist just can’t wait for the solar minima to end, and the solar maxima upswing to begin, so they can blame it all on the sun.

    My basic question is, it is increase in the TSI that causes the earth to warm a bit, or is it the solar maxima thing? Or both (the maxima impacting the TSI).

    Comment by Lynn Vincentnathan — 6 May 2009 @ 1:31 PM

  11. Lynn Vincentnathan (10) — The minima and maxima are the changes in TSI over the solar cycle; TSI drives the climate.

    While most climatologists seem to think that the global surface temperature change from a minimum to a maximum is about 0.5–1.0 K, Tung & Cabin (2008) conclude from 50+ years of data that this change is more like 0.17 K, which is quite a bit.

    Comment by David B. Benson — 6 May 2009 @ 2:31 PM

  12. Manu wrote, re #7 “According to the authors, it should indeed be significant.”

    Manu, How does this change the future big picture that we are in trouble unless we cut back on CO2?

    Carbon dioxide is a green house gas(Tyndall, IPCC, an experiment that high school kids do when they add CO2 to a beaker and the temp goes up and stays up for as long as CO2 in there [Classic Chemistry Demonstations -Royal Society of Chemistry).

    C02 has risen exponentially in the atmosphere and is staying in the atmosphere.(Keeling, IPCC).

    We humans are not going to stop emitting CO2 for any time in the near future.

    Result: we are committed to inevitable climate change and must take action.

    Secondly, how can the sun be causing big changes…it is not shown in other evidence and indeed is counter to physics.

    1) The upper stratosphere and upper atmosphere are currently cooling not warming or staying the same. This would be the opposite if the sun were really increasing in intensity.

    2) The fingerprint of the warming of the last thirty-fifty years does not indicate the Sun. It has been getting warmer faster at night then during the day over land and over the whole Earth not just hemispherically. (Someone please correct me if I am too strong in this line of reasoning).

    This was projected by Svante Arrehenius’s calculations for doubling the amount of CO2 in 1896 (Ambio Feb 1997)

    3) The Earth’s orbital changes (ice age cycles, volcanic action and polution aerosols have been trying to push the Earth’s surface temps to get cooler. Yet, some glaciers around the world are at 5000 or more year lows. Some ice shelves estimated at around 10,000 years old are falling into the ocean.

    If the Sun were causing these huge anomalies, it would probably have been hitting us in the nose with a sledge hammer and be obvious in ice cores and tree ring C 14 and Be ratios.

    4) According to paleoclimate evidence, the warming we are going through is perhaps unpredecedented in its speed-for at least the time of civilzation(Ecology (Vol. 89, No. 11, IPCC 2007). It should take thousands of years naturally with the Sun, etc. to do what just happened in 200 years. If it is the Sun, again, it should be so obvious as to be unmistakable.

    Now I could be wrong, but even if the Sun were stonger than formerly expected, the rate of warming we are going through is nearly unprededented and is eventually going to catch up with us unless we stop emitting Co2.

    Comment by Richard Ordway — 6 May 2009 @ 2:49 PM

  13. Lynn you don’t expect a cohesive argument, do you?

    They aren’t looking to explain anything. They’re looking to stop AGW being an explanation.

    If you’re BUILDING a theory, you need to ensure it is consistent. If you’re BREAKING one, all you need is something sharp and pointy.

    Comment by Mark — 6 May 2009 @ 2:52 PM

  14. “Current climate models [Intergovernmental Panel on Climate Change, 2007] have assumed that the TSI did not vary significantly during the last 30 years and have therefore underestimated the solar contribution and overestimated the anthropogenic contribution to global warming.”

    I’m not sure the conclusion – “overestimated the anthropogenic contribution” – logically follows from models wrongly assuming “TSI did not vary significantly during the last 30 years”. It would mean something was wrong, yes, but why that necessarily?

    Comment by coby — 6 May 2009 @ 3:07 PM

  15. Lynn, it depends on who you ask. Scientists by and large say it is TSI that drives solar influence on climate. Since that mechanism is too small to account for climate changes, deniers say it is the solar maximum/minimum themselves, acting in a way that magnifies the TSI effect through an unknown mechanism which most likely involves GCRs.

    Comment by RichardC — 6 May 2009 @ 7:14 PM

  16. Lynn,

    The changes in TSI between max and min of a solar cycle have little impact on the surface temperature of the planet owing to the immense intertia of the climate system coupled with a relatively short oscillation time in TSI. The differences between PMOD and ACRIM may be important for some reasons, but not for the attributuion of climate change. To make a good argument for solar impacts on climate change, you need to look at longer term trends (which have been much smaller than the amplitude of the 11-year cycle).

    Comment by Chris Colose — 6 May 2009 @ 7:34 PM

  17. I posted this earlier, but it never appeared. I am interested in how IPCC arrives at the probabilities they use in their reports. Not the “virtually certain = 99%” etc., but how they arrived at the 99% (or whatever) in the first place. Where would I look to find documentation of how the probabilities are computed?

    [Response: Here. - gavin]

    Comment by Bill Hamilton — 6 May 2009 @ 7:42 PM

  18. The bottome line as far as AGW is concerned, is indicated by two quotes from Tamino’s site “Open Mind”:

    (1)”I examined two composites of satellite measurements of total solar irradiance (TSI), and showed that whether one uses the PMOD composite or the ACRIM composite, there is solid evidence that TSI has not changed sufficiently to be responsible for modern global warming.”
    And
    (2)”….whether one uses PMOD, ACRIM, or the third contender, the IRMB composite, the change in TSI is insufficient to account for modern global warming.”
    http://tamino.wordpress.com/2007/07/27/pmod-vs-acrim-part-2/

    This is in good agreement with the IPCC 2007 Fourth Assessment Report, which shows TSI contributing 0.12{0.06 to 0.30}W/m^2, while the total net anthropogenic forcing is given as 1.6{0.6 to 2.4}W/m^2.
    http://ipcc-wg1.ucar.edu/wg1/wg1-report.html

    Comment by Lawrence Brown — 6 May 2009 @ 8:16 PM

  19. Re: #5…

    I recently attended a talk by Scaffeta. If I’m not mistaken, accepting the level of TSI-induced warming he calculates w/ the ACRIM dataset — about 70% of the past century’s warming — also requires accepting his forcing calculation, based on his “complexity” argument.

    I put the question to him directly: What’s the mechanism? He shrugged his shoulders and said “complexity.” By this, he meant, I assume, feedbacks.

    Then there’s also the issue of the stratospheric cooling fingerprint, which got another shrug.

    Comment by robert davies — 6 May 2009 @ 8:25 PM

  20. Mark (different Mark? Not Mark from the UK?) wrote in 4:

    If two papers come to different conclusions then each should find out what is wrong in the other.

    After that, pass these comments back. See what changes come up. If they still disagree and point different directions, then there is no conclusion.

    Neither are right. The long term trend is officially a known unknown.

    Not so fast…

    You might want to put Scafetta in the search box above. He has a bit of a track record. Besides, the above essay points to some weak links in the Scafetta and Willson paper. Doesn’t mean that its wrong, but the evidence and justification lean one way, not the other, and while certainty is impossible, arriving at justifiable albeit tentative conclusions is often necessary. In reality, independent of what anyone knows, chances are one conclusion is true and the other is false, at least at an appropriate level of accuracy.
    *
    Mark (he is the one) wrote in 13:

    They aren’t looking to explain anything. They’re looking to stop AGW being an explanation.

    If you’re BUILDING a theory, you need to ensure it is consistent. If you’re BREAKING one, all you need is something sharp and pointy.

    Bingo.

    Comment by Timothy Chase — 6 May 2009 @ 8:34 PM

  21. There are a couple of papers out recently by Willis, J.K and Loehle, Craig (separately) that indicate that there has been no net heating of the upper 700 meters of the ocean since about 2003. If it is true that we have a net forcing of something like 1 w/m^2, where is the energy going?carctting

    Comment by Jim Norvell — 6 May 2009 @ 11:29 PM

  22. Timothy, read the earlier bit.

    There will be issues with both papers.

    Address them.

    If there’s still no agreement when those issues are addressed, the answer is officially a known unknown.

    Comment by Mark — 7 May 2009 @ 2:36 AM

  23. Jim (#21), which paper by Willis exactly? Anyway, have a look at a longer time series, e. g. the three studies of ocean heat content for 1955-2008 superimposed in the graph on p. 13 of Levitus et al. 2009. You may want to reconsider the importance of any 5- or 6-year “trend” for the 2003-2008 period, taking into account the amplitude and duration of the wobbles about 1980-85 and 1988-1995 or thereabouts, and the fact that the long-term trend has clearly been up.

    Comment by CM — 7 May 2009 @ 3:30 AM

  24. Re #22, Is that your interpretation of the scientific method. I have read articles of many a scientists how set out to disprove something they did not agree with but ended up reinforcing it. When something becomes reinforced for a century there is more truth to it than mere falsification can find.

    Comment by pete best — 7 May 2009 @ 5:23 AM

  25. re 21.

    Dunno, but have you asked the sea below 700m?

    Comment by Mark — 7 May 2009 @ 5:29 AM

  26. Excellent post. Especially appreciated since I am very busy at work these days and don’t have the time to track these things myself. One very minor typo. In paragraph 4 you refer to SW08 instead of SW09.

    Best,
    John

    Comment by John Cross — 7 May 2009 @ 6:43 AM

  27. Gavin, I have a question I have wanted to ask for quite a while, and now that ocean heat content has come up, I’m hoping this is an opportunity.

    Isn’t the 0.85 W/m^2 used in your paper Hansen et al 2005 much too high to match up with all the empirical work on ocean heat content?

    The recent work by Domingues et al, or Levitus et al, suggest that the upper heat content of the ocean is increasing by 0.4 *10^22 J/year, and that works out to about 0.25 W/m^2. (The conversion factor of 1.6e22 is given in S1 of Hansen et al 2005).

    The heat into deeper parts of the ocean is universally agreed by modelers and measurements to be substantially less than what goes in to the top 700m, as far as I can see.

    Hansen et al 2005 cites Levitus et al 2000 with approval – but in fact they give a warming rate of 0.3 W/m^2. In the text of Hansen et al 2005 this is research is described as “Levitus et al. (15) compiled ocean temperature data that yielded increased ocean heat content of about 10 W year/m2, averaged over the Earth’s surface”
    That’s about 0.25 also, given a 40 year period being considered.

    Hansen et al 2005 then cited Levitus et al 2004, as follows:
    […] yields a global mean heat storage rate of 0.7 x 0.86 = 0.60 +/- 0.10 W/m^2 per year or 6 +/- 1 W year/m^2 for 10 years, 0.7 being the ocean fraction of Earth’s surface. This agrees well with the 5.5 W year/m^2 in the analysis of Levitus et al. (21) for the upper 700 m that was based only on in situ data.

    But it doesn’t agree at all! THAT reference estimates 0.2 W/m^2 over the Earth’s surface.

    The units here are awkward. 5.5 W year/m^2 is not a unit used in Levitus et al, but if this is over the earth’s surface, then it corresponds to a total heat increase of about 9e22 J. Levitus et al give 14.5e22 J – but that is over more than 40 years, and so the global mean heat storage rate is again something like a third to a quarter of your value.

    The analysis by Levitus et al has been improved since, and there’s the Domingues (2008) analysis as well – which you’ve blogged at Ocean Heat Content Revisions last year. But the over all trend remains steadfastly much less than Hansen et al 2005, all the time.

    I don’t get it. The paper Hansen et al seems to be citing material which consistently suggests values around a third of less of the 0.85 given with the models, but never seems to recognize this disparity. (There seems to be some recognition of a problem when you discuss eustatic sea level measures.) I use your stuff a lot, but this one has bothered me enormously. I’d really appreciate some comment.

    Do you guys still stick by 0.85 W/m^2 imbalance (+/- 0.15)? Am I misreading all the other work on sea levels and ocean heat and so on as giving a third of this or less?

    [Response: The 0.85W/m2 was the instantaneous ensemble mean value in simulations for 2005, not the the long term average (which is smaller). The models suggest that the imbalance (on average) should be growing with time, so any comparison for the long term needs to look directly at the appropriate diagnostics - as was reported in Domingues et al (2008). In the real world, the internal variability may be larger than was seen in that model (GISS-ER), but recent trends are somewhat uncertain as well (compare Levitus, Ishii and Domingues), so it seems likely that more time will be needed to have a fair assessment. We'll see. - gavin]

    Comment by Duae Quartunciae — 7 May 2009 @ 7:03 AM

  28. The link Gavin gave in response to my comment (no. 17) didn’t work. Here are two links that address the subject of uncertainties:
    http://www.ipcc.ch/pdf/supporting-material/ipcc-workshop-2004-may.pdf
    http://www.ipcc.ch/pdf/supporting-material/uncertainty-guidance-note.pdf

    Comment by Bill Hamilton — 7 May 2009 @ 7:55 AM

  29. re 24.

    It is ONE METHOD of ensuring scientific rigour.

    If two people say that the sun is changing and one says “hotter” and one “cooler”, then you ask for proof.

    When they have produced proof, you can check the proof for rigour. This should not be the person who wrote it.

    When queries about the rigour are brought forward to the writer of the piece, they can change their proof to include that change, redo the experiment to counter the proof or find that they were incorrect and withdraw their statement.

    This is what happened with the Hockey Stick.

    [edit]

    As it was, the conclusion was reinforced.

    PLEASE!!!! Ignore that people still regurgitate “the Hockey Stick is a fake” since there are people unconcerned with truth and idiots will regurgitate whatever they’ve been told is true, whether it is any more or not. Their ignorance of the result of the original concerns being that the conclusions were robust doesn’t mean that the actions described never happened.

    Comment by Mark — 7 May 2009 @ 8:09 AM

  30. Re #27: In addition to what Gavin said, it appears from this recent talk by Hansen: http://www.columbia.edu/~jeh1/2009/Copenhagen_20090311.pdf that he now thinks the ocean heat content data are compatible with a somewhat lower estimate of the radiative imbalance of 0.5 +- 0.25 W/m^2 (see charts #14 and 29 in that talk).

    To the extent that this differs from what the models predict (he quotes that as 0.75 +- 0.25 W/m^2, so there is some difference but not really outside the current errorbars on each), he seems to think that this may be due to the models tending to overestimate the climate time constant stemming from ocean mixing (see his AGU lecture here: http://www.columbia.edu/~jeh1/2008/AGUBjerknes_20081217.pdf) and that it may mean that the current radiative forcing is on the lower end of estimates because the magnitude of the negative aerosol forcing is on the high end (i.e., more negative) end of estimates.

    Of course, one could argue that it might also suggest that the climate sensitivity is toward the lower end of the estimates (again, with the caveat above that I made about errorbars). However, Hansen seems quite confident that the estimate of climate sensitivity from the ice age – interglacial cycles is quite precise, which is partly why he believes that the issue is with the time constant. (I think he has some other reasons to be suspicious of the time constant as noted in that lecture.)

    So, that at least is my reading of Hansen’s own current views on the subject, on the basis of those two recent lectures of his.

    Comment by Joel Shore — 7 May 2009 @ 11:31 AM

  31. Why the edit to #29 Gavin? There were valid problems with the graph. One was “it’s not long enough to be statistically significant”. Which was, as I recall, true. Zero effect was within the error bars at 99% confidence.

    In that instance, wait for more data and that extra data reduces the error and allowed the effect to become stronger. And it proved the graph right.

    The two things I aimed for was

    a) Saying “you got this wrong” and being RIGHT about it is skepticism.
    b) When what you say was wrong is fixed, stop saying it is wrong.

    Comment by Mark — 7 May 2009 @ 12:09 PM

  32. And further to 31, those two things are how science advances.

    Comment by Mark — 7 May 2009 @ 12:28 PM

  33. > as I recall
    Citation needed, of course. That’s how science … but you know that.
    It’s a blog. But we can try hard to give sources beyond recollection.

    Comment by Hank Roberts — 7 May 2009 @ 1:15 PM

  34. I noticed that SW09 uses Krivova et al. to bridge the ACRIM gap and come to the conclusion of a ’96 higher solar minimum. Ironically LF08 quote the same Krivova in support of the PMOD composite; indeed, the Krivova proxy shows no increase in ’96 solar minimum.

    Should I deduce that Krivova’s model works for solar maxima but not for minima? ;)

    Comment by Ricky — 8 May 2009 @ 3:50 AM

  35. Hank, what google phrase do you suggest? The noise on Google when you make ANY search on “Global Warming” and ESPECIALLY “Hockey Stick” will get you ten thousand links to tripe written by bloggers.

    Here we have access if not to those directly involved, those who are in reasonable contact with those who were.

    Comment by Mark — 8 May 2009 @ 6:13 AM

  36. Slightly off topic, but does anyone have any comments about the numbers used by David Whitehouse in the british Independent for the warming effect from a solar cycle compared to carbon dioxide?
    http://www.independent.co.uk/news/science/the-missing-sunspots-is-this-the-big-chill-1674630.html
    “…1.3 Watts of energy per square metre at the Earth. This means that during the solar cycle’s rising phase from solar minima to maxima, the Sun’s increasing brightness has the same climate-forcing effect as that from increasing atmospheric greenhouse gasses.”

    Is this right? Could this mean that a downturn in the solar activty could help to hold back GW?

    Alf

    Comment by Alf Jones — 8 May 2009 @ 2:49 PM

  37. Re: #36 (Alf Jones)

    The 1.3 W/m^2 change in solar insolation is only for an object with all its surface area directly facing the sun. Since the area of the earth is one fourth its cross-sectional area, the top-of-atmosphere radiation change due to a 1.3 W/m^2 change in solar insolation is only 1.3/4 = 0.325 W/m^2.

    And 30% of that extra insolation is reflected right back to space (earth’s albedo), so the *climate forcing* is actually a mere 0.7 * 1.3 / 4 = 0.2275 W/m^2.

    That’s nowhere near the climate forcing due to increasing greenhouse gases. If David Whitehouse has the gumption to write a book about the subject, HE SHOULD KNOW THIS. So his statement isn’t just a mistake, it’s either astounding ignorance or outright dishonesty.

    Comment by tamino — 8 May 2009 @ 3:31 PM

  38. Re #36 Alf Jones:

    eh, those 1.3 watts per square metre are referred to a square perpendicular to the direction to the Sun at the Earth’s orbit. The similar amount, also expressed in watts per square metre, of CO2 (or total, including aerosols) radiative forcing, is referred to a square at the Earth’s surface. There are four squares of the second kind for every square of the first kind… so that’s an error of 75% :-)

    It gets worse. Before that TSI variation of 1.3 W/m2 reaches the ground, 30% is bounced straight back into space, leaving only 70% of 25% = 17.5%, an error of 5.7 times…

    This mistake seems to be popular with the more clueless segment of denialism. There are some amusing but exasperating exchanges on the Internet where brave souls are trying to educate the uneducable…

    In short, does the downturn in solar activity help to hold back GW? No, not a lot.

    Comment by Martin Vermeer — 8 May 2009 @ 3:49 PM

  39. Correction: the cross-sectional area of a sphere (the earth) is one fourth its surface area. The rest of the numbers are correct.

    Comment by tamino — 8 May 2009 @ 4:13 PM

  40. Tamino and I really didn’t co-ordinate our answers, really not ;-)

    (If we had, I would have taken the opportunity to point out that four times / one quarter mix-up)

    BTW this puts paid to Theo Hopkins’s notion in another thread that if only there were no natural variability producing a flat spell every now and then in the temperature record, the “skeptics” wouldn’t be so successful at confusing the public. Well, in your dreams. They manage even to confuse simple geometry.

    Alf Jones, would you please do something for me? Wade through all seven pages of comments to the article at the Independent, and check that nobody has brought up this geometry issue (I expect nobody has). Then, post a comment of your own linking back to this discussion, pointing out that Dr Whitehouse, far from being brilliant, is an [edit]. (Use your imagination, and your legal counsel’s advice, on the last :-) )

    Comment by Martin Vermeer — 9 May 2009 @ 1:09 AM

  41. re #37 & 38 (Tamino and Martin)
    Thanks for the comments. David Whitehouse used to be a science correspondent for the BBC. It seems rather sad that instead of reporting the science he is now trying to re-invent it. I will take more care with any of the claims he makes in the future.

    Alf

    Comment by Alf Jones — 9 May 2009 @ 1:33 AM

  42. Alf,

    The 1.3 watts per square meter figure sounds bogus. Where did it come from?

    TSI varied from about 1363 to 1368 watts per square meter over the past 400 years according to Lean’s TSI reconstruction, which is the most volatile of all the ones out there. Let’s explore what that means. Say it was a steady increase over the last 50 years (not true, but let’s say it was). TSI went up 5 watts per square meter.

    Flux density absorbed by the climate system is:

    F = (S / 4) (1 – A)

    where S is the solar constant (TSI), A the Earth’s bolometric Bond albedo. The factor of 1/4 comes about because the Earth is a sphere but receives solar energy on its cross-sectional area (pi R^2 instead of 4 pi R^2). A for Earth is 0.306 according to NASA. F would then increase, given TSI moving from 1363 to 1368, from 236.48 W/m^2 to 237.35 W/m^2, an increase of 0.87 W/m^2. Where does the 1.3 W/m^2 come from?

    CAPTCHA: resumes joggling

    Comment by Barton Paul Levenson — 9 May 2009 @ 6:51 AM

  43. Mark, you asked for a suggested Google search:
    http://www.google.com/search?q=“Hockey+stick”+hand+drawn+IPCC
    The first result is:
    http://scienceblogs.com/stoat/2007/05/tggws_again_again.php
    I’m not sure exactly what you were talking about above — if you had a cite to which of the many charts you might have meant, that got edited out — but if you were talking about the original in the IPCC, Stoat covers it there.

    Comment by Hank Roberts — 10 May 2009 @ 12:28 PM

  44. The IPCC chapter on detection and attribution of climate change (working group one) mentions the solar cycle and says that studies indicate a .1 deg C oscillation in the temperature record attributable to the 11 year solar cycle. This is one reason why they say that several decades of data is needed for detection and attribution studies.

    I don’t have a link, but I’ve read Hansen saying that the change in solar input over the 11 year cycle would cause a temperature change of .2 deg C if it’s duration were longer and rise/fall of the new cycle didn’t head off further temperature change in a given direction.

    The fall off from peak to minimum only takes about 5-6 years. We are a year and a half into the longest and deepest solar minimum in a century.

    I think it’s no stretch to say that we’ve seen a change in solar forcing over the last 6 years that will, if a new solar cycle doesn’t kick in, lead to a negative forcing on the order of -.2 deg C.

    That compares favorably with the .2 deg C/decade forcing that the IPCC predicts for our GHG emissions, coming as it does in a shorter time period.

    My assesment: the pronounced and extended dip in the solar forcing we’ve seen since about Jan ’03 can indeed explain some of the recent dip in temperatures.

    It seems obvious to me, just from what I’ve read in the IPCC about the size of the oscillation in the temperature record. Don’t ask me to do any calculations relating it to TSI. :)

    Comment by Benjamin G — 10 May 2009 @ 12:50 PM

  45. Hank, #42, that link gave nothing. Just two short paragraphs.

    And, as rather expected, that google search string pulled up a lot of denialist sites and no original discourse, that likely having been bumped WELL down the list by more modern linkings.

    My statement that finding the original details is not possible using google since all the links are tertiary at best and overrun by denialists at worst.

    Do you want to try again?

    NOTE: I remember that the error in the graph for the original Hockey Stick meant that the warming trend could be X +/- 1.2X, whatever X was. Therefore it was *BARELY* possible that the change could be zero.

    The data was collected more and the X became higher and the error smaller until zero no longer was in the 3 SD limit of statistical significance.

    Comment by Mark — 10 May 2009 @ 2:15 PM

  46. No need to post this but there’s a typo in your update: \in temrs of\ should be \in terms of\.

    [Response: Thanks! Fixed. -rasmus]

    Comment by Philip Machanick — 11 May 2009 @ 5:01 AM

  47. Those who want the low in the solar cycle to reverse global warming need to explain why temperatures the last couple of years (with the help, remember, of a big La Niña) are still at relative highs vs. before 1998. NASA’s GISS land-ocean data set has 2008 as warmer than anything before 1998. Likewise for HadCRUT3: it has 2008 as warmer than any year since 1997. The combined effect of La Niña and a low in the solar cycle has only masked the underlying warming trend slightly, not pulled it back.

    Look at HadCRUT3 in the 19th century to get a sense of how much natural variation there is in the system. The little jiggles we’ve seen the last 10 years are small compared with past inter-annual variations.

    Comment by Philip Machanick — 11 May 2009 @ 5:34 AM

  48. #46

    I am NOT a believer in “it’s all the sun” theory, but I do believe that solar influence has been underestimated.

    The explanation for what you ask is simply lag in the climate systems. Solar cycle 23, remember, was relatively intense and only ended a year or two ago. Sun spot counts were high but diminishing through 2007. The near zero sun spot count is only a phenomena of the last year or so.

    Comment by Jim Cross — 11 May 2009 @ 7:29 AM

  49. Re #44 & 47–

    The 2008 GISS summary does (somewhat tentatively) attribute the slightly cooler temps of 2008 to, in part, the slightly lower insolation of this very quiet and prolonged solar minimum.

    Of course, some are trying to use this to obfuscate with the unwarranted implication that, if the sun’s doing then CO2 isn’t. Others seem quite oblivious to the point that the solar minimum is cyclical, or unreasonably convinced that it will be a new Maunder Minimum.

    Hansen’s summary (if I understood it correctly) stated that the current reduction in insolation modified the net forcing in an amount equivalent to about seven years of GHG emissions at 2008 rates, which I think puts the matter in perspective. My conclusion is that, if we’re lucky, we may have a couple of more years to act effectively to mitigate emissions. If we’re unlucky–which really means unwise–we’ll take it as an excuse to twiddle our thumbs that much longer.

    Comment by Kevin McKinney — 11 May 2009 @ 7:44 AM

  50. It may not be significant but the correlation between both sunspots and 10.7 cm radio flux and, for that matter, inverted cosic ray counts, appear to be better than for ACRIM solar insolation values.

    See http://www.climatedata.info/Forcing/forcing.html and click on sunspots

    Comment by Julius St Swithin — 11 May 2009 @ 9:32 AM

  51. I think it’s very useful to note the coincidence of the solar minimum with the current dip in global temperatures. The IPCC says we can expect a such a dip, and we’re seeing it.

    This approach completely disarms those skeptics who are busy promoting various short term temperature (or ocean heat) plots as being destructive to the IPCC’s claims.

    The claim that we should be seeing monotonic heating of the upper 700m of ocean, as Pielke and Watts have been pushing, is completely thwarted when you simply note the solar minimum and say, no, we actually expect a cooling trend of the globe (including upper ocean) during this time frame, because the drop in solar input has briefly become a larger forcing than the steady accumulation of GHGs.

    Bam, you’ve taken away at least two skeptic talking points in one blow: 1) the claim that we ‘should’ be seeing monotonic heating, 2) the claim that ‘climate scientists say it’s all about human GHGs, but what about natural variation seen before man’.

    Comment by Benjamin G — 11 May 2009 @ 9:35 AM

  52. 37# Tamino,

    “so the *climate forcing* is actually a mere 0.7 * 1.3 / 4 = 0.2275 W/m^2″

    So suddenly the GH-effect is gone?
    Why isn’t this additional solar input amplified by GHGs by around 2.5 like the rest of it? Guessing *climate forcing* is energy to the surface, or?

    Comment by lgl — 11 May 2009 @ 1:27 PM

  53. Igl, #52. IIRC, the CO2 forcing is pre-feedback too. So leaving it out is appropriate.

    Comment by Mark — 11 May 2009 @ 1:54 PM

  54. 53# Mark,

    And? 0.5 W/m2 radiative imbalance was mentioned up there, which must be to the surface after the immediate feedbacks (CO2 and H20) to make sense. So all you need to get this 0.5 W to the surface is 0.1% increase in solar, right?

    Comment by lgl — 11 May 2009 @ 4:41 PM

  55. Jim Cross writes:

    I am NOT a believer in “it’s all the sun” theory, but I do believe that solar influence has been underestimated.

    I regressed temperature anomaly on ln CO2, dust veil index, and four different measures of solar activity (the latter one at at time to avoid multicolinearity): TSI, sunspot number, years since minimum, and years since maximum. The sample size was 1880-2008 (N = 129). None of the solar measures contributed significantly. The closest was sunspot number at t = 1.4. Ln CO2, however, accounted for 76% of the variance, and DVI for 2%.

    Comment by Barton Paul Levenson — 12 May 2009 @ 6:04 AM

  56. re 54. If you recall that feedbacks were left out in the CO2 calculation too, then leaving it out with solar changes too is appropriate.

    If you do not, then no.

    Why ask anything else?

    Comment by Mark — 12 May 2009 @ 7:07 AM

  57. On the topic of the ocean surface not warming… I don’t know if there have been any studies on this, but knowing what little about physics that I do… it seems to me that if polar ice is melting and disbursing into the sea, a drop in ocean surface temps is logical, regardless of other atmospheric factors. Melt water is fresh, not saline, therefore more buoyant, and large bodies of water take much longer to catch up to ambie nt levels than many other earthy objects (think black body radiation, what gets hotter faster when placed near a fire: a metal rod or a glass of water?). This is one of the especially complicated areas of climate science, in that oceans can be a driver and a symptom of numerous climate factors. That said, I think science on the whole is making great steps in understanding and combining the myriad factors in understanding climate. We’re likely in for a few more surprises, but it really doesn’t look like TSI is one of them.

    Comment by Shirley — 12 May 2009 @ 8:11 AM

  58. Shirley, you can’t be serious.

    (Apologies to both you and Police Squad! (in color)).

    Comment by Mark — 12 May 2009 @ 9:21 AM

  59. Mark,
    I haven’t said anything about CO2 calculations. Judging by ocean heat papers 0.5 W/m2 is a significant amount of energy when over several years, for instance Lyman et al 2006, so solar seems underestimated. But of course +10 W down and +9.5 up is still 0.5 imbalance and there are lags so it’s probably to complicated for me…

    Comment by lgl — 12 May 2009 @ 10:29 AM

  60. re 59, you didn’t gainsay it either.

    Do you think you’d better check up on your figures a little better to see where they are derived from?

    Comment by Mark — 12 May 2009 @ 10:34 AM

  61. Mark,
    My figures are fine. 2.5 * 0.7 * 1.3 / 4 = 0.57 W/m^2 for 0,1% TSI increase at equilibrium. (the 10 and 9.5 was just an example)
    Your CO2 figures are 3.7 W pre-feedback and around 3*3.7=11 after I assume, for a CO2 doubling, which should be at least 3 W with the current concentration minus the negative forcings and the outgoing emission maybe ending up at 0.5 W imbalance, I don’t know.
    And when there is balance, like the last 5 years, you simply adjust the negative forcing a little and doomsday is still right around the corner, unbeatable.

    Comment by lgl — 12 May 2009 @ 12:19 PM

  62. #42 Barton,
    Reading between the lines … Whitehouse says the there is a 0.1% variation in the solar irradiance between minima and maxima over the 11 year cycle. So 0.1% of 1360Wm-2 = 1.3Wm-2.
    I think the variation over a solar cycle is nearer 0.08% so even his 1.3Wm-2 is probably too big.

    Alf

    Comment by Alf Jones — 16 May 2009 @ 3:36 AM

  63. Igl, #61, so why are you complaining about feedbacks when you’re only using examples? If you’re not using the real values, any feedback will make the false ones you’re using even more wrong.

    Comment by Mark — 16 May 2009 @ 9:56 AM

  64. lgl writes:

    > the outgoing emission maybe ending up at 0.5 W imbalance, I
    > don’t know. And when there is balance, like the last 5 years ….

    What? It seems you’re assuming what you claim you’re proving.
    You claim to know the radiation budget for the planet from what source?
    Did you get Triana launched, and keep the data to yourself?

    Please publish.

    Comment by Hank Roberts — 16 May 2009 @ 10:03 AM

  65. All I’m saying is that papers indicate you would need 0.5 W/m2 to explain the rise in OHC, and that is not more than the surface gains from a 0.1% increase in solar.

    Comment by lgl — 17 May 2009 @ 8:06 AM

  66. And I think what Hank is saying Igl(#65) is that your reading is incorrect and wishes you to publish how you attained that value.

    Comment by Mark — 17 May 2009 @ 8:24 AM

  67. Well I know how to read but do not understand all of it. From Lyman et al 2006 and other places 0.5 W/m2*1year=1E22 J for the upper 700 meters, and the GHE is a positive feedback loop with gain 0.6 giving an amplification of 2.5. What I’m missing is the time constant. How long will it take to reach say 75% of equilibrium SST after a forcing step up?

    Comment by lgl — 18 May 2009 @ 10:30 AM

  68. The sun spot activity determines the number of cosmic rays striking the Earth’s atmosphere and as a result how many particles are ionized. This may have a large effect on the formation of clouds and as a result the climate. Read the papers by Svensmark to learn more about this interesting model. If it is correct, CO2 is irrelevant, at least as the main driver of the climate.

    [Response: "If" is the operative word. See here, here and most recently, here and here. - gavin]

    Comment by sn — 20 May 2009 @ 4:29 PM

  69. sn, why not learn some real physics before veering off into the speculative. I’d be very interested to learn how your cosmic rays cool the stratosphere for instance. Good Lord!

    Comment by Ray Ladbury — 20 May 2009 @ 7:58 PM

  70. lgl, “where there is balance” — where are you finding a balance between incoming and outgoing radiation? Or are you just saying you believe there must be one because you have a five year trend that proves … anything?

    Comment by Hank Roberts — 20 May 2009 @ 11:31 PM

  71. It is not even correct to say that *if* cosmic rays have a significant climate influence, it follows that CO2 is close to irrelevant. Why we must always settle for those “either-or” games is beyond me. Given the uncertainty surrounding climate sensitivity and the total forcing provided by anthropogenic aerosol input, there’s still some reasonable wiggle room for forcings which have not yet been quantified or may have been overlooked, it just doesn’t look like they can be very important.

    Because there has been no secular trend in cosmic rays for many decades, it does not appear they can be be very important in the global warming signal. Certainly no reasonable policy decisions should abandon radiative physics and stuff which has been around for over a century and can be confirmed in the lab or by models quite well, just for this hypothesis which hasn’t evolved into anything convincing. The actual physical mechanisms (even if there was a trend in cosmic rays) is IMO quite unsatisfactory as a scientific theory. I’ve still yet to hear a feasible explanation as to why cosmic rays shouldn’t impact high clouds as much as low clouds.

    Comment by Chris Colose — 21 May 2009 @ 11:57 AM

  72. re: Chris.

    Yup. Weird.

    Denialists say “The IPCC must be wrong because they only consider the CO2 to be effective in climate change. Well what about…?”

    And then when they’re saying why it isn’t CO2, they say that it must be “something else” without saying why CO2 isn’t having an effect any more.

    Comment by Mark — 21 May 2009 @ 2:42 PM

  73. Chris (71),

    You’re absolutely right pointing out that even *if* cosmic rays have a significant effect on climate, it doesn’t negate the radiative effects of CO2 and everything we know about the climate system, something that some folks tend to forget in their desire to jump to certain conclusions.

    There is however a feasible explanation as to why cosmic rays shouldn’t impact high clouds as much as low clouds, put forward by Yu (http://www.albany.edu/~yfq/papers/Yu_CR_CN_Cloud_Climate_JGR02.pdf). It may not be the final word on it, since his modelled nucleation rates tend to be more sensitive to ion concentration than other models, but it may be feasible nevertheless.

    Here’s what I wrote about it in the aerosol nucleation & climate post (http://www.realclimate.org/index.php/archives/2009/04/aerosol-effects-and-climate-part-ii-the-role-of-nucleation-and-cosmic-rays):

    Based on his model for ion induced nucleation, Yu found that at low altitude, the number of particles produced is most sensitive to changes in cosmic ray intensity. At first sight, this may be a surprising result in light of the increasing cosmic ray intensity with increasing altitude. The reason is that high aloft, the limiting factor for particle formation is the availability of sulfuric acid rather than ions. Above a certain GCR intensity, increasing ionization further could even lead to a decrease in ion induced nucleation, because the lifetime of ion clusters is reduced (due to increased recombination of positive and negative ions). In contrast, at low altitude particle formation may be limited by the ionization rate (under certain circumstances), and an increase in ionization leads to an increase in nucleation.

    Comment by Bart Verheggen — 23 May 2009 @ 6:53 AM

  74. Hank,

    Fig. 5 here for instance http://etienne.berthier.free.fr/download/Cazenave_et_al_GPC_2009.pdf

    Comment by lgl — 24 May 2009 @ 4:46 AM

  75. Thanks Bart.

    There are a couple other papers I wanted to point out, if they haven’t been already throughout the comments. One is a recent paper in GRL by Pierce and Adams on cosmic rays (http://www.agu.org/pubs/crossref/2009/2009GL037946.shtml). They conclude that hypothesized changes in Cloud Condensation Nuclei from cosmic ray fluctuations over the solar cycle are far too small to explain changes in cloud-cover extent, and so changes in the cosmic ray flux during the 20th century have likely had little impact on the present-day climate shift. They suggest further research into other mechanisms aside from the popular “ion-aerosol clear-air” hypothesis.

    The other paper is http://www.agu.org/journals/pip/gl/2009GL037519-pip.pdf (PDF file, no abstract available yet since it is still in press) where the authors assume that the solar irradiance changes are entirely caused by the evolution of the solar surface magnetic fields and use solar surface magnetic field distributions and compare with the populat TSI composites, PMOD, ACRIM, and IRMB. The best agreement is achieved with the PMOD composite, and any long-term trend in solar irradiance cannot be due to the surface magnetic field

    [Response: My reading of the Wenzler et al paper is that if solar irradiance changes are caused by (or correlated to) magnetic variability, then PMOD is the best fit. If irradiance changes are not not solely driven by magnetic changes, or if there are additional factors that perhaps do not impact the magnetics, then it is still unclear, though your last line still holds. This is important for longer term reconstructions too because both 10Be and 14C rely on the magnetic field-to-irradiance connection to work. - gavin]

    Comment by chris colose — 24 May 2009 @ 3:48 PM

  76. LGL, you’re claiming a “balance” of incoming and outgoing heat.
    You point to a PDF as your source for claiming this.
    That’s a comparison of sea levels, not of radiation balance.
    What’s your real source?

    Comment by Hank Roberts — 24 May 2009 @ 4:02 PM

  77. By the way, lgl, the first page of that PDF says their study raises the question:
    “… could the recent rate of sea level rise (since 2003) be explained by fresh water input to the ocean …”?

    Here’s an answer: http://www.agu.org/pubs/crossref/2009/2009GL037525.shtml
    McPhee, M. G., A. Proshutinsky, J. H. Morison, M. Steele, and M. B. Alkire (2009), Rapid change in freshwater content of the Arctic Ocean, Geophys. Res. Lett., 36, L10602, doi:10.1029/2009GL037525.

    Comment by Hank Roberts — 24 May 2009 @ 4:09 PM

  78. Re #68 where sn says:

    “The sun spot activity determines the number of cosmic rays striking the Earth’s atmosphere and as a result how many particles are ionized. … If it is correct, CO2 is irrelevant, at least as the main driver of the climate.”

    CO2 is not the main driver of the climate. It is well known that water vapour has more effect as a greenhouse gas, and that changes in cloud cover have an even greater effect on weather and climate. The main driver is solar radiation.

    It may well be that changes in cosmic radiation can influence cloud cover, but that does not alter the fact that if we increase the carbon dioxide content of the atmosphere too much we will cause a catastrophe. We do not know if cosmic rays affect the clouds, nor do we know how much CO2 is too much!

    Comment by Alastair McDonald — 25 May 2009 @ 4:30 AM

  79. I don’t know but this might be of interest for some:
    http://www.ltu.se/tkg/avd/Geovetenskap/d24226

    Nordic Palaeomagnetic Workshop

    Comment by Magnus Westerstrand — 25 May 2009 @ 5:51 AM

  80. Chris (75), I discussed the paper by Pierce and Adams in the same post as mentioned above.

    Comment by Bart Verheggen — 25 May 2009 @ 7:39 AM

  81. Alastair, when sn wrote in 68:

    The sun spot activity determines the number of cosmic rays striking the Earth’s atmosphere and as a result how many particles are ionized. … If it is correct, CO2 is irrelevant, at least as the main driver of the climate.

    … the first thing I would remind him of is that we understand the physics behind warming due to CO2 as result of its increasing the opacity of the atmosphere to infrared radiation. If he doubts that carbon dioxide has this effect upon infrared radiation, he might want to check out the following:

    Aqua/AIRS Global Carbon Dioxide
    http://svs.gsfc.nasa.gov/vis/a000000/a003400/a003440/index.html

    The dark orange off the east and west coasts of the United States? That is carbon dioxide at roughly 8 km altitude — infrared at 15 μm in wavelength has been absorbed and emitted at lower levels of the atmosphere, but this is where it gets emitted for the last time before escaping to space — and as such the brightness temperature at that wavelength reflects the cooler temperature at that altitude – and signifies the trapping of thermal energy in the layers below it.

    Thus if he is trying to come up with an alternative explanation for the era of modern global warming (from 1975 to present), he can’t simply give an alternative explanation, but now must provide an explanation as to why a mechanism that is well-understood didn’t give rise to this warming, e.g., suggest some cooling mechanism that cancelled out the warming due to carbon dioxide trapping thermal radiation.
    *
    Alastair McDonald wrote in 78:

    It may well be that changes in cosmic radiation can influence cloud cover, but that does not alter the fact that if we increase the carbon dioxide content of the atmosphere too much we will cause a catastrophe. We do not know if cosmic rays affect the clouds, …

    Well, we do know that there isn’t much of any correlation between cosmic rays (which show quasi-periodic behavior but not trend) and global warming.

    Please see for example:

    Uncooperative cosmic rays
    http://cce.890m.com/solar-cosmic-rays/#_ednref27

    However, I notice that Gavin has provided him with some additional reading material. (See the inline response to 68 above.)
    *
    Alastair McDonald wrote in 78:

    … nor do we know how much CO2 is too much!

    Here is something that might interest you, Alastair:

    Tropical ‘Runaway Greenhouse’ Provides Insight into Venus
    http://www.nasa.gov/centers/ames/news/releases/2002/02_60AR.html

    Comment by Timothy Chase — 25 May 2009 @ 11:24 AM

  82. Alastair McDonald (78) — My somehwat informed opinion is that anything above 290 ppm CO2e is too much in the long run.

    [reCAPTCHA appears to agree, entoning "devilry way".]

    Comment by David B. Benson — 25 May 2009 @ 2:10 PM

  83. Thanks Timothy for the pointer to that NASA Release: 02-60AR “TROPICAL ‘RUNAWAY GREENHOUSE’ …” — I knew I’d seen that somewhere.

    Alastair, photographing the upper atmosphere in the bands where CO2 emits would seem convincing, wouldn’t it? I recall this coming up as a possible test of your idead a few years ago, before that satellite went up.

    Comment by Hank Roberts — 26 May 2009 @ 9:10 AM

  84. Hank, 76#

    It shows thermosteric level is almost unchanged which means OHC has not changed which means radiative balance.

    Comment by lgl — 26 May 2009 @ 10:52 AM

  85. Hank Roberts wrote in 83:

    Thanks Timothy for the pointer to that NASA Release: 02-60AR “Tropical ‘Runaway Greenhouse’ …” — I knew I’d seen that somewhere.

    No problem.

    Incidentally, here is a paper by the same individuals dated 2004:

    The Runaway Greenhouse Effect on Earth and Other Planets Maura Rabbette, Peter Pilewskie, Christopher McKay, and Richard Young
    http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20040171753_2004168321.pdf

    Actually I believe what they are referring to is the same phenomena known as the “Super Greenhouse Effect”:

    Satellite studies (8–10) have found that for clear skies and SSTs above 298 K, the spatial variation of Ga with SST, dGa/d(SST), exceeds the rate of increase of sea surface emission, ds(SST)4/d(SST) = 4σ(SST)3. For a tropical SST of 300 K, 4σ(SST)3 ~ 6.1 W m-2 K-1. This effect, termed the “super greenhouse effect” (11), occurs in both hemispheres during all seasons. It is also observed for interannual variations of Ga with SST during the El Nino in the tropical Pacific (12). Observations in the tropical Atlantic ocean (11) show that the clear sky downwelling infrared flux incident on the surface (Fa-) also increases faster than the surface emission with increasing SST. The net result is further warming of the surface, which in turn induces additional heating of the atmosphere column above.

    Direct radiometric observations of the water vapor greenhouse effect over the equatorial Pacific Ocean
    F.P.J. Valero, W.D. Collins, P. Pilewskie, A. Bucholtz, and P.J. Flatau
    Science, 274(5307), 1773-1776, 21 March 1997

    I would have to look it up, but also believe that this was another one of those phenomena predicted by climatologists prior to its actual observation.

    Comment by Timothy Chase — 26 May 2009 @ 11:12 AM

  86. lgl, and you believe the first claim based on that short time span how?
    And the “which means” steps in your logical sequence — how?
    Are you getting whata you’re posting from somewhere?

    Start with the first “it shows” claim you make — how long a time span is needed for that particular data set to detect a significant likelihood that there is really a trend?

    Or are you just looking at the picture and ignoring what the researchers say in the text of the article it’s from?

    Comment by Hank Roberts — 26 May 2009 @ 11:29 AM

  87. To say there is radiative balance based on 5 years of data is a rather bold conclusion, I would say. Remember that the oceans are a huge heat reservoir.

    Comment by Ray Ladbury — 26 May 2009 @ 12:15 PM

  88. lgl wrote in 84:

    Hank, 76#

    It shows thermosteric level is almost unchanged which means OHC has not changed which means radiative balance.

    Actually another thought comes to mind.

    When in 74 you refer us to:

    http://etienne.berthier.free.fr/download/Cazenave_et_al_GPC_2009.pdf

    … it shows the sea level continuing to rise – in fact it even appears to be rising more quickly than only a few years ago, although I myself can’t say whether this is statistically significant. However, according to the text, the rising sea level mostly as the result of melt water from land — which is increasing the mass of the ocean. This afterall is what the Grace satellite measurements are all about that are mentioned in the article.

    This being the case, you have ice cold melt water from Greenland and Antarctica (for example) entering the ocean raising the sea level. But what else will ice cold melt water do? Cool things off — I believe, essentially bringing the temperature of the ocean down from what it would otherwise be, in all likelihood cancelling out what would be a warming trend.

    However, here is something else to keep in mind. When you point to the fact that the increase in volume is not due to heat content but additional mass, ice cold water will itself have a smaller volume than the surrounding water, and thus will decrease the volume to mass ratio, or alternatively increase the mass to volume ratio — otherwise known as the “density.” Likewise, when it cools the surrounding water it will increase the density of that water and decrease the volume that it takes up. And you are basing your argument off of the fact that while the volume is expanding, this expansion is not due to thermal expansion.

    Ice water lowering the temperature of sea water from what it would otherwise be and slowing the rate at which the ocean warms is not what I would consider to be evidence of “radiative balance.”

    Thank you for the link to the article.

    Comment by Timothy Chase — 26 May 2009 @ 1:30 PM

  89. > ice cold fresh water

    Yep. See the article on that, linked in the post
    at 24 May 2009 at 4:09 PM

    Comment by Hank Roberts — 26 May 2009 @ 5:01 PM

  90. Hank Roberts wrote in 89:

    Yep. See the article on that, linked in the post at 24 May 2009 at 4:09 PM

    77. Understood.

    Actually I think that my whole response was a bit more wordy than it needed to be — but I was in a hurry. I believe that pretty much all that needed to be said is that if sea level is rising and therefore volume is increasing (and it would appear to be increasing more rapidly than before) but this is due to increased mass rather than thermal expansion, then that additional water has to be coming from somewhere. About the only place that large volumes of water can come from (particularly when absolute humidity is rising) is from melting ice.

    Sea ice. Greenland’s ice. Antarctica’s ice. Glaciers. And each of these, it would appear, will tend to lower the temperature of the ocean, or alternatively, reduce the rate at which the ocean warms, thereby diminishing thermal expansion. So if the volume is increasing but the rate of expansion due to temperature has flattened, then obviously there is still a radiation imbalance in the ocean itself, but it is being masked by the ice-cold melt water.

    With that said I must admit that fresh water will typically be less dense than salt water — and consequently my bringing in water density was inessential to the argument and flawed. I left an opening — but having corrected myself that opening is now closed.

    Comment by Timothy Chase — 26 May 2009 @ 8:08 PM

  91. Timothy! All god stuff!

    You are correct in my view with the observation that the melting ice and the warming oceans are all acting as global heat-sinks which are masking the forcing of GHG on surface temperatures. This has the potential to become a major up-tick in the global surface temperature trend because the more the ice sheets fracture and expose their surface area the faster they will melt and the more they suppress air temperature rise as they do so. But as they approach end of melt then we loose that heat sink and the forcing returns full on.

    This gets a bit angrier too when we consider:

    June 2008.
    Global warming twenty years later: tipping points near: James Hansen
    http://www.columbia.edu/~jeh1/2008/twentyyearslater_20080623.pdf

    “…if emissions follow a business-as-usual scenario, sea level rise of at least two meters is likely this century. hundreds of millions of people would become refugees. no stable shoreline would be reestablished in any time frame that humanity can conceive.”

    “…the disturbing conclusion, documented in a paper I have written with several of the world’s leading climate experts, is that the safe level of atmospheric carbon dioxide is no more than 350 ppm (parts per million) and it may be less. Carbon dioxide amount is already 385 ppm and rising about 2 ppm per year. stunning corollary: the oft-stated goal to keep global warming less than two degrees celsius (3.6 degrees fahrenheit) is a recipe for global disaster, not salvation.”

    and in May 2009:
    “The new projections, published this month in the american meteorological society’s journal of climate, indicate a median probability of surface warming of 5.2 degrees celsius by 2100, with a 90% probability range of 3.5 to 7.4 degrees. this can be compared to a median projected increase in the 2003 study of just 2.4 degrees. ”

    http://globalchange.mit.edu/news/news-item.php?id=76

    so: in May 2009 MIT scientists running a sophisticated and well-respected climate model tell us that there is a median probability that the earth will be 5.2 degrees celsius warmer by 2100.

    and: in 2008 Hansen stated that even 2 degrees celsius of global warming ‘…is a recipe for global disaster…’, and …if emissions follow a business-as-usual scenario, sea level rise of at least two meters is likely this century. … … no stable shoreline would be reestablished in any time frame that humanity can conceive.”

    Thus: Given our practical inability to return CO2 levels below 350 ppm, and the new predictions of global temperatures by 2100, global sea level rise is both inevitable and unstoppable by mankind.

    Bother.

    Comment by Nigel Williams — 26 May 2009 @ 10:35 PM

  92. This paper concludes by offering a testable prediction with regard to climate change.

    http://adsabs.harvard.edu/abs/2003ESASP.535..317D

    jh

    Comment by jh — 27 May 2009 @ 8:17 AM

  93. Yes of course. If you mix a bucket of water containing 10 units of energy with another containing 5 units of energy then the total will be around 10. 10+5=10 yeah that’s very close.

    Comment by lgl — 27 May 2009 @ 11:39 AM

  94. lgl wrote in 93:

    Yes of course. If you mix a bucket of water containing 10 units of energy with another containing 5 units of energy then the total will be around 10. 10+5=10 yeah that’s very close.

    You have been arguing that since (presumably) there has been no thermal expansion of the ocean that the ocean is in radiation balance.

    You wrote in 84:

    It shows thermosteric level is almost unchanged which means OHC has not changed which means radiative balance.

    … where It referred to figure 5 of the paper:

    http://etienne.berthier.free.fr/download/Cazenave_et_al_GPC_2009.pdf

    Now you speak of units of energy and/or heat.

    However, heat per se doesn’t cause thermal expansion. If the ocean consisted of four liters of water at 5°C and you added one liter of water at 5°C there would be no thermal expansion, but only expansion due to mass. Increased temperature causes thermal expansion.
    *
    Since the expansion of the ocean from increased mass (~80% of total expansion) has been due to ice melt where the ice melt is colder than the ocean it is pouring into, we know that if the ocean were in radiation balance there should have been thermal contraction. So even if the thermal expansion of the ocean were neither positive nor negative but exactly zero we already know that the ocean is not in a state of radiation balance.

    However, not all of the expansion of the ocean can be accounted for by increased mass. Therefore some of the expansion has been due to net thermal expansion and net warming. (Roughly 20%, it would appear judging from the paper you referred us to.)
    *
    Now to get at the figure from which you argued that there has been no thermal expansion to the ocean you had to skip over the abstract, pass over three pages of main text and pass several other figures. You were looking at Figure 5 which shows little or no thermal expansion.

    However the other figures showed expansion due to increased mass and increased mass as the result of ice melt. Figure 1 shows expansion due to increasing mass. Figure 2 shows expansion due to increasing mass as the result of ice sheet contribution.

    Figure 3A shows expansion due to increasing mass as the result of Greenland’s ice sheet loss. Figure 3B shows expansion due to increasing mass as the result of Antarctica’s ice sheet loss. Figure 4 shows altimetry-based sea level rise and the smaller contribution of land-ice melt to this sea level rise.

    Even if you entirely avoided the abstract and the main text, you would have had to avoid five figures to avoid realizing that the ocean was expanding, and you would have had to avoid four figures to avoid realizing that the expansion from increased mass was due to ice melt — where ice melt would have the effect of lowering the temperature of the ocean and reducing thermal expansion.

    It would be very difficult to attribute your “mistake” to either ignorance or stupidity. At this point I can only conclude that it is pointless to argue with you.

    Comment by Timothy Chase — 28 May 2009 @ 2:03 AM

  95. jh, what testable prediction do you see in that paper?
    Could you find any subsequent research citing that paper and saying something about testing a prediction from it?

    Comment by Hank Roberts — 28 May 2009 @ 10:54 AM

  96. Timothy,
    Ok, so I’m 0.004 W/m2 wrong, the power needed to heat 2 mm of seawater from 0 to 15 C in one year. (heat capacity 4,2 kJ/kg/K)

    Comment by lgl — 30 May 2009 @ 3:26 AM

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