A Guide to the Global Warming Debate

My new column at Forbes is a post I have been thinking about and working on for quite a while, trying to refine over time a simple explanation of what is and is not understood in climate science.  This is how it begins, but I hope you will read it all

Likely you have heard the sound bite that “97% of climate scientists” accept the global warming “consensus”.  Which is what gives global warming advocates the confidence to call climate skeptics “deniers,” hoping to evoke a parallel with “Holocaust Deniers,” a case where most of us would agree that a small group are denying a well-accepted reality.  So why do these “deniers” stand athwart of the 97%?  Is it just politics?  Oil money? Perversity? Ignorance?

We are going to cover a lot of ground, but let me start with a hint.

In the early 1980′s I saw Ayn Rand speak at Northeastern University.  In the Q&A period afterwards, a woman asked Ms. Rand, “Why don’t you believe in housewives?”  And Ms. Rand responded, “I did not know housewives were a matter of belief.”  In this snarky way, Ms. Rand was telling the questioner that she had not been given a valid proposition to which she could agree or disagree.  What the questioner likely should have asked was, “Do you believe that being a housewife is a morally valid pursuit for a woman.”  That would have been an interesting question (and one that Rand wrote about a number of times).

In a similar way, we need to ask ourselves what actual proposition do the 97% of climate scientists agree with.  And, we need to understand what it is, exactly,  that the deniers are denying.   (I personally have fun echoing Ms. Rand’s answer every time someone calls me a climate denier — is the climate really a matter of belief?)

It turns out that the propositions that are “settled” and the propositions to which some like me are skeptical are NOT the same propositions.  Understanding that mismatch will help explain a lot of the climate debate.


  1. MNHawk:

    The fraud behind the 97% figure


    is the same kind of fraud behind this whole religion.

  2. Joel:

    Nice piece, although I suspect that a lot of people who would benefit from reading this will get turned off and dismiss it after the early (and largely unnecessary) Ayn Rand reference.

  3. Mike H:


    Great article, it's my new goto article when talking to people about Global Warming. I agree about the Rand reference though, unfortunately people will use it as an excuse to ignore the article.

  4. jimc5499:

    If people are biased enough to quit reading the article after the Rand reference it is unlikely that they would have gained anything from it.

    Warren, your point about water vapor is dead on. I have to wonder what would happen if Hydrogen ever becomes a primary energy source, after all it's exhaust would be water vapor?

  5. jdh:

    Well done!

    I tend to agree with Joel and Mike's point though. I think you want to look for new converts, as opposed to preaching to the choir.

    But excellent, nonetheless.

  6. joshv:

    This is the fundamental point I cannot get past - how can one "accept" 1 degC/doubling if one posits offsetting feedbacks that will reduce that number?

    Does one accept 1 degC/doubling as some sort of unobservable ideal - what would happen without certain other complex climate effects?

    If the feedbacks turn out to be negative, and the real effect is 0 degC/doubling, how does it make any sense to say that you accept the basic physics of CO2 based warming? In that case the 1 degC/double from "physics" is an unobservable phantom.

  7. Xmas:


    The 1 deg C per doubling of CO2 is an ideal condition based on the physics of the gases in the atmosphere. This is a tested phenomenon, you can make a miniature version of the atmosphere in a glass box, put a full spectrum lamp on it, read the temperature until it stabilizes, then double the amount of CO2 (or whatever other gas or particulate) and then find the new stable temperature. Voila, you get an ideal lab result that you can now compare to the field results, and a starting point for a dozen debates in why they differ.

  8. joshv:

    No Xmas, there is no lab experiment that can be done to establish climate sensitivity.

  9. Chris:

    Joshv: You can't just say "not that's not true" without any further evidence or support. Well, I guess you can, but not with any credibility or impact.

  10. joshv:

    Ok Chris, point me to the paper documenting the lab experiment that establishes climate sensitivity.

  11. T M Colon:

    My take on the accusation of questioning MGW is like being a holocaust denier.

    Someone claims the Nazis killed 200 million victims. I say that is wrong, the number is a tenth of that. Because I think their number is too high, this somehow means I think the Nazis didn't kill anyone.

  12. JA:

    Here is something to ponder; if scientists cannot explain the historical climate, how can they presume to explain (predict) the climate 10, 50, 100 years from today?
    For instance; what caused the ice ages? what caused the ice ages to end? how is it that every ice age ended in global warming? how is it that every warm period in the earth's history ended in an ice age or colder period? How is it that during the very very warm periods when dinosaurs roamed the earth that CO2 did NOT build up (due to very abundant plant growth AND DECOMPOSITION)to the point where the earth got hotter and hotter and hotter? - instead, it all ended in an ICE AGE !!
    In face, historically speaking, what caused all the variations in climate that the earth has experienced?
    Further, the "preponderance of opinion," (irrespective if it is 95% or 50.0001%) is NOT science; it is an opinion, it is politics. Why would a real scientist resort to arguments such as this if they had REAL (not some computer "model") evidence to support their contention? Recall that Einstein's Theory of Relativity , when first introduced, was contrary to the "opinion" of the "other" 95% or so of physicists who firmly "believed" that Newtonian Mechanics pretty much explained all that was needed to be explained aside from a few minor "loose end."
    Finally, why is it that about 95% of AGW supporters are liberal progressives, socialists or communists??

  13. Goober:

    ...Or that you are a Nazi sympathizer.

  14. michael:

    answer to jimc5499:

    And what if all the energy on earth would be produced from winds and waves?

    This would interrupt the natural patterns of climate, just like water dams caused changes in eco-system down the rivers.
    I mean, If you take energy away from wind or ocean you alternate the eco-system.

    This means all those new wind and ocean power plants are not sustainable.

    I am a Mechanical Engineer with specialization in Fluid Mechanics, Heat and Aeronautics.

  15. Zachriel:

    Warren Meyer: Let’s look at the actual propositions the 97% agreed to in one such study conducted at the University of Illinois. Here they are: 1. When compared with pre-1800s levels, do you think that mean global temperatures have generally risen, fallen, or remained relatively constant? 2. Do you think human activity is a significant contributing factor in changing mean global temperatures? The 97% answered “risen” and “yes” to these two questions. But depending on how one defines “significant” (is 20% a significant factor?) I could get 97% of a group of science-based skeptics to agree to the same answers.

    Even granting the somewhat broad definition of "significant", that is a very strong consensus among experts in the field supporting anthropogenic climate change.

    This NOAA chart might help clarify matters, and disentangle other possible causes of global warming. It shows data from a variety of sources.

    In particular, note that the lower troposphere is warming, as is the surface. Meanwhile, the stratosphere is cooling, the signature of anthropogenic global warming.

  16. Zachriel:

    Zachriel: the signature of anthropogenic global warming.

    That should read, the signature of greenhouse warming.

  17. Jon F:

    From the article:

    3.Warming only matters if it is harmful, so there are a variety of theories about how warming might increase hazardous weather (e.g. hurricanes, tornadoes, floods, droughts), raise sea levels, or affect biological processes.

    How about we re-word it this more truthful way: "Warming only matters if the fossil fuel industry's profits are affected..." I think that's more to the point. All the $$ wouldn't have been spent by the oil/gas/coal industry for misinformation campaigns otherwise!