Friday, December 21, 2012

"Use [the lack of warming] as an opportunity to communicate honestly with the public..."

Commentor Hoo persists in claiming that his "statistical" analysis proves that this graph of the past 16 years of earth's temperature shows... warming:


Graph of global temperatures for the past 16 years
that demonstrates "warming", according to warmists. 


Here's what actual climate scientists say about the obvious lack of global warming for the past 16 years.

Dr. Judith Curry, chair of the School of Earth and Atmospheric sciences at Georgia Institute of Technology, and one of America's pre-eminent climate scientists:

[Judith Curry's] note to defenders of the idea that the planet has been warming for the past 16 years 
"Raise the level of your game. Nothing in the Met Office's statement or in Nuticelli's argument effectively refutes Rose's argument that there has been no increase in the global average surface temperature for the past 16 years. 
Use this as an opportunity to communicate honestly with the public about what we know and what we don't know about climate change. Take a lesson from these other scientists that acknowledge the 'pause', mentioned in my previous post Candid comments from global warming scientists"

In addition, Dr. Curry responds to the argument that a "statistical analysis" of the data shows warming:

"how does this refute [the no-warming] argument? No statistically significant positive trend, and it makes it look like SkS [the warmist website that put up the calculator] hasn’t done their homework with the latest data."

Here's Dr. Kevin Trenberth, head of the Climate Analysis Section at the USA National Center for Atmospheric Research:

"The hiatus [in warming] was not unexpected. Variability in the climate can suppress rising temperatures temporarily, though before this decade scientists were uncertain how long such pauses could last. In any case, one decade is not long enough to say anything about human effects on climate; as one forthcoming paper lays out, 17 years is required"
Curry is fairly skeptical of global warming alarmism, and Trenberth is one of the Climategate crooks.

When the leading skeptics and the leading crooks agree that there's been no global warming for 16 years, and you have a graph of the data that obviously shows no warming, who are ya' gonna believe, warmists' "statistics" or you're lyin' eyes?

14 comments:

  1. Dr. Egnor,

    You have started yet another thread on the same topic. This makes an impression that you are trying to run away. You can run, but you can't hide.

    In this thread you say that you provide snippets of quotes from Dr. Curry, relying (yet again) on a secondary source, this time the Global Warming Policy Foundation. In this way, you cherry-pick (yet again) the scientist's words. This is called, technically, lying by omission.

    In fact, Dr. Curry's opinion is much more nuanced than what you have presented here. She does not deny the presence of a warming trend in the last 15 years. In fact, she states quite unequivocally on her own blog that there has indeed been slight warming. Here is a quote:

    Is the first decade+ of the 21st century the warmest in the past 100 years (as per Peter Gleick’s argument)? Yes, but the very small positive trend is not consistent with the expectation of 0.2C/decade provided by the IPCC AR4. In terms of anticipating temperature change in the coming decades, the AGW dominated prediction of 0.2C/decade does not seem like a good bet, particularly with the prospect of reduced solar radiation.

    Has there been any warming since 1997 (Jonathan Leake’s question)? There has been slight warming during the past 15 years. Is it “cherry picking” to start a trend analysis at 1998? No, not if you are looking for a long period of time where there is little or no warming, in efforts to refute Hypothesis I.


    Dr. Curry does not argue against the existence of global warming. If you read the linked post then you will see that her argument is different. She says that we expected to see a warming trend of +0.2 degrees per decade in the early 21st century. The data from multiple sources, including HadCRUT4, are consistent with +0.1 degree per decade (within two sigma), but less so with either the lack of warming or with +0.2 degree per decade.

    Please go ahead and read Dr. Curry's post, then come back and acknowledge that you have twisted her words to suit your ideological point. This is a shameless tactic, Dr. Egnor, unbecoming of an academic.

    Hoo

    ReplyDelete
    Replies
    1. I'll give your censure all the consideration it deserves.

      Curry has been generally level-headed about AGW. Her comments in my post speak for themselves-- her words were quoted verbatim, and linked, without twisting.

      I should point out that her statement "the very small positive trend ..." is a term of art (as you well know), and means no statistically significant change, which she reiterates in the quote I provided.

      I've always respected Curry, who seems to be honest about AGW. She certainly does believe that there has been warming over the past 2 centuries, which no one doubts. The human contribution is debatable. She has been harshly critical of the crap that there is a "consensus" about AGW, and about the "denialist" rhetoric.

      I debate with you not because I think that you're anything but a jerk, but because I think that it is useful to show honest people what dishonest science is like. Your amusing "statistics" applied to a graph that obviously shows no warming is a real gift.

      Keep giving.

      Delete
  2. And with that, I will repost the numbers for the temperature trend obtained from HadCRUT4 from various starting dates until today:
    1995–2012: +0.109±0.119 °C/decade
    1996–2012: +0.107±0.131 °C/decade
    1997–2012: +0.058±0.136 °C/decade
    1998–2012: +0.052±0.153 °C/decade
    1999–2012: +0.095±0.162 °C/decade
    2000–2012: +0.056±0.179 °C/decade

    Here is another question for Dr. Egnor.

    Do you acknowledge that there is a warming trend in the data, whether or not you cherry-pick the starting date?

    Dr. Curry says yes, there is, albeit not as large as predicted. What do you say, Dr. Egnor?

    Hoo

    ReplyDelete
    Replies
    1. "Trend" has a very specific meaning in science-- it refers to statistically insignificant change.

      I'll grant you the insignificance of "warming" in that data.

      Delete
    2. Going the lawyer's route, Dr. Egnor? I sympathize with you.

      No, the word trend does not have that "very specific meaning in science." But if you insist on scientific terms, let's use them.

      We are talking about the time dependence of the average global temperature anomaly ΔT as a function of time t. Specifically, ΔT(t) = ΔT(t0) + β(t−t0). Here t0 is a starting point in time and β is the linear slope.

      So, do you agree, along with Dr. Curry, that the HadCRUT4 data set (among others) yields a positive β even if you cherry-pick the starting point? The values of β for various starting points are quoted in my previous comment.

      Hoo

      Delete
    3. And then of course there are unanswered questions in a previous thread.
      A brave warrior you are not, Dr. Egnor.

      Hoo

      Delete
    4. Of course "trend" has a very specific meaning when reporting data. It refers to change that fails to reach statistical significance. Data always shows change-- the question is whether the change in the data represents meaningful change in the thing measured. "Trend" is what you say when a statistical analysis of your data shows that there is no justification for asserting that the change in data represents genuine change in the thing that data measures.

      "Trend in global temperature over 16 years" means "no significant change in global temperature over 16 years".

      My own research involves analysis of the relationship between arterial pressure waveforms and intracranial pressure waveforms, using transfer functions. I've been staring at a lot of data (on the Q factor of a transfer function notch) for the past week that looks a lot like the global temperature graph. There are plenty of "trends", but nothing that is outside of confidence intervals.

      As an honest scientist, I would never claim that that data shows a real change in the Q factor. It make me sick that climate scientists would think of saying such things about such data. Just frauds.

      Delete
    5. "A brave warrior you are not, Dr. Egnor."

      I make no claim of courage. I merely let you talk, and add my modest comments.

      Delete
    6. Dr. Egnor,

      You are twisting in the wind. Please answer the question stated in strict scientific terms.

      Hoo

      P.S. And if you insist that the word "trend" in science refers to a "change that fails to reach statistical significance" then perhaps you should provide some well-sourced definition. I am a scientist more than you are and I am not familiar with this "definition."

      Delete
    7. I don't know who you are, Hoo. You could be typing from a locked mental ward for all I know.

      I love anonymous commentors who chest thump and pull credentials.

      Delete
    8. Dr. Egnor,

      My credentials do not matter. Indeed I may be typing from a mental ward. But our words do matter. And it is quite clear to anyone that you are merely trying to bluff your way through.

      Hoo

      Delete
    9. "My credentials do not matter.'

      Then why invoke them?

      Delete
    10. Dr. Egnor,

      You continue to pursue various irrelevant distractions. I would rather that you answered my straightforward question. You seem reluctant to do so.

      Hoo

      Delete
    11. As to the matter of what trend means in statistical analysis, I advise you to read the Wikipedia article Trend estimation. Therein the trend is defined as "the slope of the least squares line... a common convention." Nowhere does the article say that a trend is "change that fails to reach statistical significance," as you say.

      It looks like Dr. Egnor is seriously wrong.

      Hoo

      Delete