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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 47801 to 47850:

  1. helenavargas at 06:37 AM on 8 March 2013
    What doesn’t change with climate?

    Apologies for the HTML not working in my post #6.  Hope its intent can still be read.

    If 'source' input isn't seen as source, what have I missed??

    tx --bc/hv

    Moderator Response: [RH] Voila!
  2. helenavargas at 06:33 AM on 8 March 2013
    What doesn’t change with climate?

    Folks -- Where can one find a 24-h-averaged, (α,β)moon-averaged visible spectrum of sunlight reflected by the earth incident on the moon?  By now, someone will have calculated model-dependent predictions of such spectra, so your statements about temperature changes on the lunar surface -- which endures month-long 'days', of course -- might have data against which to be checked.  Would like to be able to visualize what a warmed earth would look like from space, other than cloudier.  Having spent decades in the JHKL part of the NIR spectrum, I'd like to see a 'bluer' = visible representation of future reality.

    KR (#5):  Technical question:  isn't the change in equilibrium sufficiently small (δT/T over time) more or less adiabatic, preserving the blackbody nature of the earth's climate?  Naively, it would seem tough to do the physics otherwise.

     

  3. Cherrypicking to Deny Continued Ocean and Global Warming

    And Kevin, you still don't get it: the theory of anthropogenic global warming is not based on the surface temp trend.  It could be plummeting, and CO2 would still be doing its thing.  What you need to focus on is not "global warming" but "model projections."  You are not going to falsify the greenhouse effect, and, yes, I'll put money on it.

    You continue to look for a simplistic sound bite: "global warming has stopped."  What we're really talking about here is "global surface temp has flattened in recent years; there are several factors that could be driving this, and there are scientists focused on these factors."  No one is investigating whether or not CO2 has stopped working.

  4. Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    And just a further point on CO2 and glacials. While Milankovitch forcing pace the glacial cycles, there wouldnt be any glacial cycle if CO2 concentration was higher. The milankovitch forcings were still there before the Quaternary. Its just that CO2 was too high before that for them to significantly affect planetary albedo.

  5. Cherrypicking to Deny Continued Ocean and Global Warming

    16 years, Kevin -- very intentionally.

    If you find me evidence for your last assertion, I just might believe you.  As far as I know, very few sensitivity studies are based on the recent surface temp trend, and none of those conclude high sensitivity. 

  6. Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin, I was questioning whether this statement of yours is true:

    As I stated before, AGW (removed the C) states that the warming originates in the atmosphere. If it slows, halts, increases, stops, starts, whatever, here, it will then and only then, continue on to the oceans, starting with the upper layer first. Regardless of whether there is an energy imbalance or not, it the temp increase stalls in the atmosphere, that will dictate a stall in global warming.

    I'm still under the impression that the above is not true. At your comment #54 you say that global warming can have said to have stopped if there were to be 30 years of no warming trend (in the surface temperature trend I assume) even if there was evidence of a continuing energy imbalence. From what I think I understand, with a continued enegy imbalance, as expected from the relativley steady rise in GHG, the surface temperature trend is expected to do what it has done in recent decades and get back on a significantly upward trend. So OK, I get your point that if this doesn't happen then there is something amiss with the theory of AGW. But it seems unlikely to me that as you put it, this hypothetical "scintific method -data overruling theory type of thing" will be realized. I'll leave it to others that are more knowledgable and articulate on this topic than myself to say more if they are inclined.

  7. What doesn’t change with climate?

    Changing greenhouse gas concentrations causes an energy imbalance between incoming/outgoing energy.

    1. More GHGs reduce total outgoing IR at all temperatures (reducing outgoing energy)...
    2. That difference between incoming and outgoing accumulates, warming the climate...
    3. Until, at a higher climate temperature, the Earth is once again radiating as much as it is receiving. 

    There are indeed frequencies in IR that have increased with current warming. But if you integrate energy over the entire IR spectrum, the sum of outgoing energy is presently lower than incoming. The final at-equilibrium IR spectra of the Earth, under increased GHGs, will show warmer peaks but a more jagged outline, integrating to the incoming 240 W/m^2 from the sun. 

  8. What doesn’t change with climate?

    This statement doesn't quite accord with my layman's understanding:

    "...before climate equilibrium is reached, the outgoing radiation from Earth would be reduced..."

    I understood [or thought I understood] that a warming planet will omit more Long Wave radition into space except at those wavelengths trapped by the GHGs and that this can [perversely] mean that even as more Long Wave radiation to outer space is inhibited by GHGs the overall level of non-inhibited radiation can increase the total OLWR.

    I shall be grateful if a better Scientist than I can confirm or deny my understanding or [gently] point me in the right direction.

  9. Cherrypicking to Deny Continued Ocean and Global Warming

    Roger D,

    Please re-read what I wrote.  You are not paraphrasing it correctly.

    (-snip-).

    (-snip-).  That is the extent of that particular point.

     

    DSL,

    How long of time frame was the 2007 rate calculated on?  Was it 16 years? 27 years?

    And yes, some scientist did believe it would persist, or we wouldn't have heard of the 2 - 6 C increase predictions. 

    Moderator Response: [DB] Sloganeering snipped.
  10. Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin, you say: "At the current rate, after an additional 100 years, the temp will rise an additional 0.4 - 0.8 C.  That does not seem that significant, and in fact will achieve the outcome of keeping the temp increase to less than 2 C."

    Yes.  At the current linear trend.  Do you expect that trend to persist?  In 2007, did you expect the .284C per decade trend to persist?  You must have, or you're being inconsistent.  Again, do you think scientists thought it would persist?  

    By the way, the current rate of warming is still 9x that of PETM event warming.  There's significance and then there's significance.

  11. Rob Honeycutt at 05:25 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Those figures again....  I dropped the 2-sigma range and typed one of the figures wrong...

    GISS since 1995 = 0.113 ±0.112 °C/decade (2σ)

    GISS since 1973 = 0.166 ±0.037 °C/decade (2σ)

  12. Cherrypicking to Deny Continued Ocean and Global Warming

    Composer99 - Actually, surface temperatures are more than adequate to judge warming. 

    But that's true if, and only if, you examine enough data for statistical significance, say 30 years worth or more. The "no warming since 1997" claimants such as Kevin fail in that regard. 

  13. Cherrypicking to Deny Continued Ocean and Global Warming

    Although it's been pointed out that total energy accumulation in the "system" is continuously growing, Kevin seems to be saying that an essentially steady global warming cannot be considered to be occuring because there are changes in trends that approach zero for he surface and tropsopheric temperature record.The response given by Composer99@ 37 addresses this. 

    Is there any physics-based reason to think that the oceans cannot continue to gain heat energy without the surface temps mirroring them? It seems like their shouldn't be, as longs as thre is water, ice, air, land to allow heat energy flow

    (sorry if this question is in the too-basic catoagory)

  14. Dikran Marsupial at 05:11 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin, you appear not to understand statistical hypothesis testing.  If you want to make a claim (such as "the temp increase has slowed") on the basis of a set of observations, you need to show that the Null hypothesis, i.e. the opposite of what you want to claim (in this case "the temp increase has not slowed") and show that the observations are not consistent with that  null hypothesis.

    Hypothsesis tests are not symmetric, the lack of a statistically significant trend does not mean that there has been no warming, just that you can't rule out the possibility that it hasn't warmed.

    The "margin of error" as you call it, also include the long term trend, so the observations don't rule out the possibility that warming has stopped, but they don't rule out the possibility that warming has continued at the same rate either.  Hence you cannot draw the conclusion that you did on statistical grounds.

    You would benefit from dropping the hubris a bit, and just consider the possibility that you don't understand the issue quite as well as you think you do.

  15. Rob Honeycutt at 05:10 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin...  You can't compare a trend that is not statistically significant with one that is and expect that you're revealing anything.

    GISS since 1973 = 0.166/decade

    GISS since 1995 = 0.116/decade

    Both statistically significant.  Both well within model projections.

  16. Cherrypicking to Deny Continued Ocean and Global Warming

    Does it really matter if the surface or upper ocean warming has slowed down in recent years?

     

    Figure 2 clearly shows that the ocean warming down to 2000 meters has continued unabated after 1997, 1998 or whatever year the denialists prefer to start from.

     


    From 1997 to 2010 the oceans accumulated about 10 x 1022 J of energy, which is sufficient to heat the entire atmosphere by 20oC.

    The rate of warming was about 0.45 x 1022 J per year from 1966 to 1997 and 0.77 x 1022 J per year from 1997 to 2010, so the warming has in fact accelerated, not slowed down!

     

    And the reason?

    Definitely not the sun, since the present solar cycle seems to peak at the lowest level since the 1880s.

    Maybe it's time to start listening to the scientists who predicted this warming many decades ago?

     

  17. Cherrypicking to Deny Continued Ocean and Global Warming

    Dikran, (41)

    What has the warming rate been for the past 16 years?

    Compared to the warming rate of the past 30 years, which is greater?  By what ratio?

    Do we really need to be this explicit?

    Moderator Response: [DB] All parties...and most especially Kevin, please take the discussion of "16 years" to that most-appropriately-named thread. If it is deemed to have already been covered there, it will be adjudged as sloganeering and be moderated accordingly. Thanks in advance for everyone's compliance and understanding in this matter.
  18. Rob Honeycutt at 05:02 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin @ 42...  Wrong.  That is a completely inaccurate statement.

  19. Dikran Marsupial at 05:01 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin, please don't play games.  What does the lack of a statistically significant trend actually mean in terms of what we can conclude about global climate from that set of observations?

  20. Rob Honeycutt at 05:00 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin @ 38...   If the trend is not statistically significant that merely means that that you have a noisy data set.  It means you can't rule out a zero trend, but you also can't rule out a higher trend either, all at the 95% confidence level.

    A trend that is not statistically significant means that you need more data.  Once you go back far enough to get a statistically significant trend, what do you have?

  21. Cherrypicking to Deny Continued Ocean and Global Warming

    Dikran Marsupial,

    It means that the statement "There has been no significant warming for the past 16 years" is accurate.

    Moderator Response: [DB] All parties...and most especially Kevin, please take the discussion of "16 years" to that most-appropriately-named thread. If it is deemed to have already been covered there, it will be adjudged as sloganeering and be moderated accordingly. Thanks in advance for everyone's compliance and understanding in this matter.
  22. Dikran Marsupial at 04:58 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin wrote: "What is important is, the temp increase has slowed"

    The observations do not support that statement (at least not from a statistical perspecive).  To assert that this is the case, you need to show that there has been a statistically significant change in the rate of warming, which you have not done.

  23. Cherrypicking to Deny Continued Ocean and Global Warming

    Composer99,

    It would help if you respond to what other people atually write rather than resorting to quote-mining. Such behaviour is extremely disingenuous and frankly reflects poorly on you.

    What/where are you referring to?

    (-snip-)

    Moderator Response: [DB] Sloganeering and excessive html snipped.
  24. Did Murdoch's The Australian Misrepresent IPCC Chair Pachauri on Global Warming?

    http://vvattsupwiththat.blogspot.com/2013/02/postmodern-geochemistry-semiotic-carbon.html

  25. Did Murdoch's The Australian Misrepresent IPCC Chair Pachauri on Global Warming?

    Murdoch's take on the subject requires<a href="http://vvattsupwiththat.blogspot.com/2013/02/postmodern-geochemistry-semiotic-carbon.html"> a new approach to the carbon cycle as we know it </a>

  26. Ari Jokimäki at 04:46 AM on 8 March 2013
    What doesn’t change with climate?

    And after re-reading, read this:

    http://skepticalscience.com/no_global_warming_from_cosmic_rays.html

  27. Dikran Marsupial at 04:45 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    The warming trend over the last 16 years is not statistically significant.  What do you think that actually means?

  28. Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    RH - Erm, sorry about that. Not sure what happened.

    Moderator Response: [RH] No problem. I'm not quite sure what happened either.
  29. Cherrypicking to Deny Continued Ocean and Global Warming

    Dikran Marsupial,

    Let me ask the question from the opposite direction, has there been significant warming over this 16 year time frame?

    Make sure the same criteria applies as to what is significant.

     

     

  30. Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin:

    It would help if you respond to what other people atually write rather than resorting to quote-mining. Such behaviour is extremely disingenuous and frankly reflects poorly on you.

    You also need to adjust your conception on what global warming is, and how the surface temperature record reflects global warming:

    As I stated before, AGW (removed the C) states that the warming originates in the atmosphere. If it slows, halts, increases, stops, starts, whatever, here, it will then and only then, continue on to the oceans, starting with the upper layer first. Regardless of whether there is an energy imbalance or not, it the temp increase stalls in the atmosphere, that will dictate a stall in global warming.

    The Earth surface temperature, specifically, and atmospheric temperatures generally, are highly variable as a result of energy exhange between the atmosphere and other components of Earth system climate (mainly the cryosphere and the ocean).

    One very prominent energy exchange is ENSO (El Niño/La Niña). During El Niño phases the net transfer is from the oceans to the atmosphere (increasing Earth surface temperature); the reverse is the case during La Niña years. But - and this is a very big but - ENSO does not fundamentally alter the Earth energy balance.

    It is no surprise that one of the main reasons it even looks like there has been a "pause" is because there was an extraordinarily strong El Niño in 1998 and the last several years have been characterized by neutral or La Niña phases.

    Bottom line: what you continue to insist is a pause is, based on the current evidence, an artifact of atmosphere-ocean energy exchange.

    The way global warming can be said to be paused is if the energy imbalance at top-of-atmosphere can be shown to have disappeared and the Earth climate system as a whole can be shown to no longer be accumulating energy. Surface temperatures are unsuitable for this purpose.

  31. Dikran Marsupial at 03:49 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin, a trend that is not significantly positive does not mean that there has been a pause; losely speaking it essentially means that the observations do not rule out the possibility of a pause.  Anybody that claims that there has been a pause on the grounds of a non-significantly non-zero trend doesn't understand statistical hypothesis testing properly.


    Furthermore, as has been pointed out, cherry picking the start date invalidates the hypothesis test anyway (unless you compensate for the implicit multiple hypothesis testing).

  32. Cherrypicking to Deny Continued Ocean and Global Warming

    Smith, can you honestly tell me that if you glanced at that post (and the majority of viewers of Watts' site won't do more than glance at most of the posts) you wouldn't have assumed the straight line drawn on the graph was a trend line? If it had been meant just to highlight a period it would have been more natural to draw it above or below the actual data points to avoid such confusion, or far better still to use a double headed arrow or a highlighter block, rather that a line the same width a trend line would be.

    It's not a duck and Dana didn't call it a duck, he called it a fake duck.

  33. What doesn’t change with climate?

    "How can you say "This means that the Sun doesn’t change,"?

    We know very well that solar activity is variable"


    The article says the sun's output doesn't change as a result of climate change on earth, not that the sun's output doesn't ever change.


    I suggest you re-read the article, perhaps more than once.


  34. Cherrypicking to Deny Continued Ocean and Global Warming

    Smith @19 - quite simply, lines on graphs in this situation usually depict linear trends.  But if you want to play that game, I didn't accuse Watts of calling his yellow line a trend.  I hope you're not holding me to a higher standard than you're holding Wattsy.

    Kevin - choosing a starting point at an anomalously high (or low) point is the very definition of cherrypicking.  If you want to argue that global warming has 'paused', make the argument by using real statistics instead of BS cherrypicking.  Except you can't, because it hasn't.  The only way to make the argument is with ultra-cherrypicking, as discussed in this post.

  35. Rob Honeycutt at 03:31 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Smith said... "Watts never claimed the yellow line was a trend."

    That's a fantastically lame excuse for being lazy.  In fact, lazy in a very deliberate manner.  

    Watts flies off the handle for the most minor errors of others but thinks he gets a pass on this?  No way!

  36. Cherrypicking to Deny Continued Ocean and Global Warming

    If there were really a pause in global warming, as revealed by the surface temperatures, we would need to see a negative temperature trend whose confidence intervals did not also overlap a positive number.

     

    Wrong.  That would imply that there was a decrease in the temperature, not a pause in the warming! 

    That is my point!  Get rid of the two "escalator" stairs and compute your own trend line from 1997 to the present.  The result is very close to a slope of 0, with the margin of error greater than the slope.  That means it is not significant!

    • NASA GISS: 0.081 ± 0.132°C/decade
    • NOAA NCDC: 0.044 ± 0.121 °C/decade
    • HADCRUT4: 0.046 ± 0.124 °C/decade

    So what I said in 25, quoted above is inline.  The margin of error is larger than the slope.  At the current rate, after an additional 100 years, the temp will rise an additional 0.4 - 0.8 C.  That does not seem that significant, and in fact will achieve the outcome of keeping the temp increase to less than 2 C.

     

    As is noted in myriad other posts on this site - and in fact on this very post - the majority of the excess energy (around 90%) goes into heating the oceans. The basis of your claim is the behaviour of the Earth surface, which represents but 2-3% of the additional energy accumulation and is therefore subject to much wider variability.

    As I stated before, AGW (removed the C) states that the warming originates in the atmosphere.  If it slows, halts, increases, stops, starts, whatever, here, it will then and only then, continue on to the oceans, starting with the upper layer first.  Regardless of whether there is an energy imbalance or not, it the temp increase stalls in the atmosphere, that will dictate a stall in global warming.

     

     

     

  37. Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    Andy Skuce @ 55

    I thought yours an excellent question too. I have been in touch with Dr Gavin Foster, who has very kindly given permission for his response to be posted in comments here:

     

    "That is a good question and well spotted.  Our interpretation
    here (built on early work by us - Foster et al. 2012 attached) is 
    that actually there must have been some northern hemisphere
    ice growth during the middle miocene. This is in line with a
    number of other indicators (e.g. ice rafted debris in the north 
    atlantic). This does however conflict with a straightforward 
    reading of the Zachos' benthic foram d18O curve.  
    Its important to note though that this is not global temperature - 
    rather its actually a mix of ice volume and temperature but 
    the temperature of deep sea, not a global average surface.  
    Deep water forms at high latitude so this is telling us about 
    high latitude temperature predominantly. A recent paper by
    Herold et al. (2011; Paleoceanography) compiled a number 
    of independent deep water temperature estimates for the 
    Miocene and showed that deep water was around 6 oC warmer than 
    today - that will account for a large chunk of the d18O 
    change from Miocene to recent (~1 permil).  We dont know 
    why this is right now but clearly the Zachos d18O curve is not as 
    straightforward as it first appears.The best support for 
    our interpretation is we know from several sources (using 
    different techniques from geochemical to stratigraphic) that 
    there was ~70m of sea level fall during the middle 
    miocene climate transition (the cooling that terminated the 
    middle miocene warm period).  In the absence of northern 
    hemisphere ice this would have to be all Antarctica based ice, 
    yet we know from ice proximal drilling that the Antarctic ice 
    sheet was very much in existence during the Miocene (and 
    indeed since the early Oligocene, 34 million years ago), 
    though it may have been reduced slightly.  This raises lots of 
    more questions of course and we dont know all the answers 
    yet but we are working on it!"

    [Foster et al. (2012) abstract]
    Moderator Response: [RH] Fixing page formatting (I hope). ...Okay. Mostly fixed. :-)
  38. Doug Bostrom at 03:12 AM on 8 March 2013
    Cherrypicking to Deny Continued Ocean and Global Warming

    Smith: All I am wondering is why?

    Because Watts is a great artist of the Impressionist* school. There are pointilists and more lately there are linealists, with Watts being among the latter and intent on conveying an impression of a scene that is in fact not what it looks like at first glance. 

    *A literary style characterized by the use of details and mental associations to evoke subjective and sensory impressions rather than the re-creation of objective reality.

  39. What doesn’t change with climate?

    This is the worst essay I've seen on this venue so far. It's upside down from start to finish.

    How can you say "This means that the Sun doesn’t change,"?

    We know very well that solar activity is variable, that the relationship between the Earth and the sun is variable, that variability in the sun's magnetic field influences the amount of cosmic rays that reach the Earth, which influences cloud cover.

    The is a terrible post-hoc argument for human causation of climate variability.

  40. Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    Kevin

    Also see Chris Colose # 64

  41. Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    Kevin - if the by far largest part of the scale of temperature swings due to forcing changes is indeed long term CO2 levels (as is evident), then it is indeed dominant, and other factors are secondary

    And if that dominant factor, CO2 level, changes independently from (for example) temperature-dependent ocean solubility with temperature, the biological pump, and silicate weathering, then we should expect to see temperature changes. As observed.

    If you have any evidence (paper links would be appropriate, continued semantic quibbling would not) demonstrating that CO2 is not the largest factor, then by all means present it. So far, I have seen nothing of the sort from you. 

     

  42. Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    Kevin

    Please see # 47 previous page and # 51 above and links. Too much argumentation, not enough reading.

  43. Rob Honeycutt at 02:52 AM on 8 March 2013
    Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    Kevin...  I sure hope that "astrological events" is a typo on your part.  I don't think you're going to find anything in any of the published literature about how the phases of scorpio or cancer will influence global temperature.

  44. Cherrypicking to Deny Continued Ocean and Global Warming

    Kevin:

    Kindly refrain from paraphrases if you are going to misrepresent what is said.

    First, the data do not say what you think they are saying.

    The top-of-atmosphere radiative imbalance (reported by NASA to be currently 0.8 W m-2, across the entire surface of the Earth) means that every second the Earth accumulates an additional 4.08 x108 Joules of energy over and above its current heat content. That energy has to go somewhere.

    As is noted in myriad other posts on this site - and in fact on this very post - the majority of the excess energy (around 90%) goes into heating the oceans. The basis of your claim is the behaviour of the Earth surface, which represents but 2-3% of the additional energy accumulation and is therefore subject to much wider variability.

    In order for global warming to have genuinely halted, it must be the case that the radiative imbalance at top-of-atmosphere is no longer present. As far as I am aware no self-styled skeptic has yet to present evidence showing that this is the case.

    So your characterization is entirely false.

    Second, the surface temperature record is not a meaningful marker of global warming. 

    As described immediately above, surface and/or lower troposphere temperature records account for perhaps 2-3% of global warming.

    As such, an apparent pause in the surface temperature record just doesn't reveal very much. What would be reavealing is a statistically-significant pause in ocean warming coupled with empirical findings of a long-lasting change in the TOA energy imbalance.

    Third, even granting for the sake of argument that the surface temperature record is meaningful, the 1997-present trend does not mean what you think it means.

    Using the Skeptical Science trend calculator, the period 1997-2013 has the the following trends (using the datasets that are compiled in the "Escalator" graphic):

    • NASA GISS: 0.081 ± 0.132°C/decade
    • NOAA NCDC: 0.044 ± 0.121 °C/decade
    • HADCRUT4: 0.046 ± 0.124 °C/decade

    The calculator indicates these are 2σ results, so (unless I am mistaken) there is a 95% probability that the actual temperature trend over this period lies within the range given by the ± values.

    Because the confidence intervals overlap '0', we cannot rule out the possibility that surface temperatures have not increased in this timeframe. But - and this is a very big but with respect to your claim - we also cannot rule out the possibility that they have increased more rapidly.

    If there were really a pause in global warming, as revealed by the surface temperatures, we would need to see a negative temperature trend whose confidence intervals did not also overlap a positive number.

    So, for example, the 1994-present GISTEMP trend is 0.135 ±0.106 °C/decade, which is the earliest trend in GISTEMP on the SkS trend calculator where the 2σ confidence interval does not overlap 0.

    If, instead, the trend over that period was -0.135 ± 0.106 °C/decade, then we could be confident there was a pause of some kind (in the surface temperature record, anyway).

    Finally, it is self-styled skeptics, not defenders of the science (who you smear as "CAGW subscribers") who are making hay over the statistically-insignificant period 1997-present, or indeed, over statistically-insignificant timeframes in the surface temperature record in general - or, in Watts' case as discussed in the OP, in the OHC record of 0-700 m depth of ocean.

  45. Cherrypicking to Deny Continued Ocean and Global Warming

    DSL@22 - Your claims to understand Watts' motivations are immaterial to my point.  Watts never claimed the yellow line was a trend, Dana knew this, yet it was labeled a "Denial Fake Trend" anyway.  All I am wondering is why?

  46. Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    KR,

    There are no misconceptions on my part.  The title of this article claims that CO2 is the dominant control of sea level over the past 40 million years.  That is quite a claim.  It is interesting to note that everyone here has noted the role the Milankovich cycles has played in starting and stopping the ice ages.  However,

    This strongly supports the dominant role of CO2 in determining Earth’s climate on these timescales and suggests that other variables that influence long-term global climate (e.g., topography, ocean circulation) play a secondary role.

    this is the quote from the abstract of the paper.  Note the absense of any mention of Milankovich cycles or any other astronomical occurance.  It is also interesting to note that the reference sources listed for the paper do not list any regarding astrological events.  Did the author compare CO2's role to that of Milankovich cycles?  Don't know.But if no comparison was made, then clearly the author can't claim that CO2 is the dominant force. 

  47. Cherrypicking to Deny Continued Ocean and Global Warming

    OPatrick@20 - I have to disagree.  The Watts article has the figure labeled "Sure looks like a pause to me, especially after steep rises in OHC from 1997-2003. Note the highlighted period in yellow:"

    He calls it a highlighted period.  A period is not a trend.

    Besides, Dana1981@11 clearly states "to be fair, Watts didn't say the yellow line was a trend, just that he was 'highlighting'".  So my question still stands.  Why call it a "Denial Fake Trend", when Watts never claimed it was and Dana also knew it wasn't?

    If it's not a duck, even though it looks like one and sounds like one, I would argue that calling it a duck anyway certainly isn't very scientific.

     

  48. Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    KR, you should have bolded "but the end temperature swing is much higher with that positive feedback than it would be with just the initial forcing."  That seems to be the stumbling block.

    The thermostat, when left alone, brings the room to the designated equilibrium.  The thermostat has several control knobs.  The CO2 knob (amongst others, e.g. CH4) moves when the Solar Variation knob moves, but the CO2 knob can also be moved independently.  When the Solar Variation knob moves, the CO2 knob moves at several times the rate of SV movement. Indeed, it has the greatest range of movement of any of the knobs (if we tie SV's range to its geo-historical likely range).  Water vapor has a knob, but it's tied to all the other knobs, and it has a powerful spring that kicks it back to its pre-existing state almost immediately. 

  49. Rob Honeycutt at 02:23 AM on 8 March 2013
    Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    BillEverett...  I actually don't disagree with you.  I think the difference is minor (if any difference at all).  I guess I get frustrated with how "skeptics" can so easily misinterpret the meaning to be something completely wrong.  Thus I want to come up with iron clad phrasing.

  50. Rob Honeycutt at 02:20 AM on 8 March 2013
    Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years

    jzk...  It looks like you got the answer to your question @71 from BBD back at comment #37.

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