Chris de Freitas: Rebuttal of Jim Salinger’s wild Alarmist Claims in the NZ Herald

Posted: May 29, 2013 by tallbloke in alarmism, Analysis, atmosphere, climate, Clouds, Cycles, Natural Variation, Uncertainty

Hothouse cover b

From the New Zealand Herald

Several aspects of Jim Salinger’s op-ed “Climate hurtling towards a hothouse Earth” (Herald 24/5/13) are quite misleading.

It is true most climate scientists would agree that rising carbon dioxide in the atmosphere due to fossil fuel use could affect global climate. The basic physics is there to support this view. But there is no evidence that the putative change would be large or damaging. Output from computer models is not evidence unless model performance has been validated. So far, it has not.

The so-called evidence of minor human-caused climatic change can also be attributed to causes or processes other than those related to the increase of carbon dioxide in the atmosphere.

What is rarely mentioned by climate alarmists is the incontrovertible fact that adding more carbon dioxide to the atmosphere has an ever-decreasing effect on global temperature. To illustrate this, compare covering a glass window with very thin paint. The first coat of paint cuts out some light, the second some more; but each subsequent coat has an ever decreasing effect on light shining through.

It is true, the warming effect of increasing carbon dioxide concentrations never reaches zero (saturation); but, for significant global warming to occur, increased concentrations must set in motion positive (or destabilising) feedback processes.

Such processes would cause temperatures to rise by some other mechanism. One such mechanism is increased evaporation caused by higher temperatures leading to rising water vapour concentration, which is by far the most important greenhouse gas. This would increase retention of energy from the Sun and lead to further warming, and so on.

To date, scientific evidence suggests that negative (stabilising) feedback processes prevail; possibly due to the cooling effect of increased cloudiness from water vapour increase. If true, this means it is unlikely higher concentrations of carbon dioxide in the atmosphere will greatly influence global climate.

Negative feedback processes are played down by climate alarmists who assume climate is governed by positive feedback processes which they claim will lead to runaway global warming. Four billion years of global climate history shows that negative feedbacks prevail.

Climate warming does not confirm that carbon dioxide is causing it. The evidence would have to distinguish between human-caused warming and natural warming. This has not been done.

Climate is always warming or cooling. There are natural variability theories of warming. Much of the talk of “increasing evidence for global warming” is actually evidence of climate variability.

Whatever the cause of the current warm phase, its occurrence is not unprecedented. Global warming happened from 1850 to 1940, then cooling to 1979. During the Medieval Warm Period from 900 to 1200AD, the Vikings sailed in arctic waters that are now covered with sea ice, and farmed Greenland soil that is now too cold for agriculture.

From the results of research to date, it appears the influence of increasing carbon dioxide on global warming is almost indiscernible. Future warming could occur, but there is no evidence to suggest it will amount to much.

One could reasonably argue that lack of evidence, one way or the other, is no reason for complacency.

I will concede that.

Chris de Freitas is a teacher and researcher in the School of Environment at the University of Auckland.

  1. michael hart says:

    Excellent. A nice, short, easy to understand, description of one of the most important aspects of the “global warming” story.

    Of course, most readers here will already know that many of the ‘climate-gate’ crew wanted to get De Freitas fired for being an editor who published science articles that THEY disagreed with. It’s worth recalling.

    So much for peer-review in climate-science.

  2. PeterMG says:

    We are at a very dangerous point in the climate debate. The argument over changing temperatures has been won, with any increases or decreases over that last century being insignificant. What caused this variability is also indeterminate with a variety of causes all strong possibilities. The so called measured increase in CO2 is probably NOT one of them. It has also been demonstrated that science has been subjugated for political ends. So what could be wrong?

    I believe that for far too long too many sceptics and too much time has been expended on the short term temperature record and not enough time on understanding the full role of CO2 in the evolution of earth. For it is only by understanding the past can we get any grip on what’s happening in the present.

    I feel that many sceptics run the risk of agreeing with bogus science (radiative forcing) so as to become accepted (or welcomed back) into the very system they have been fighting. Chris de Freitas has been great for the cause but his adding “It is true most climate scientists would agree that rising carbon dioxide in the atmosphere due to fossil fuel use could affect global climate. The basic physics is there to support this view.” is wrong if not qualified. He is not the first sceptical scientist to say something similar over the past few weeks.

    The more I read about life and the evolution of our planet the more I’m convinced we misunderstand much of the science surrounding our environment. Life has been the key to why our planet is different. And the 2 ingredients in the environment key to life are water and CO2. Life is the reason we still have water, that and the chance happening that we are 93million miles from the sun. Without life there would have been no O2 and no O3 to protect the water molecules from disassociation by ultraviolet radiation. And life could not have produced that O2 without CO2.

    So what atmospheric pressure has the earth been in the past? If we use Venus as a starting point we must have been over 100 bar at some point, nearly all CO2. And the dolomite and limestone suggests that life has been far more abundant in the past than now. The CO2 hasn’t all disappeared overnight and as recently as 150 million years ago when animals reputedly grew to 100 tons the atmosphere must have contained a lot of CO2 and O2 because there is no way you can reasonably explain such large organisms in the context of a one bar atmosphere.

    Now if the above is true, or even has a grain of truth then the Arrhenius theory is toast. In fact it fails every other sanity check but that’s another story. This brings me back to the danger of appearing too lenient on those that have bombarded us with bogus science. We will end up going another thirty years waiting for their hiatus to pass and the instant we see a microscopic rise again they will be off and we will be paying 95% tax. No I say we have to bury Arrhenius and radiative forcing for ever. As ever feel free to disagree with me.

  3. michael hart says:

    I’ll take you up on some of that, PeterMG.

    For example, there are plenty of reasons to think that life was abundant before oxygen became so abundant in the earth’s atmosphere. For long, oxygen was the waste product of photosynthetic life forms, and is still toxic to many obligate anaerobes.

    Sceptics are frequently criticised for the diversity of objections to the “CO2 story”. I consider that to be largely because we have so much to aim at, and individuals will have their own areas of specialist knowledge. Some points are more objectionable than others, but the temperature changes, or rather the lack of them, is the mainstay of the warmist argument and most easily understood by lay readers.

    If the models cannot even get that right then I consider most subsidiary arguments less worthy of limited discussion time. Those who don’t have the time, will, or ability, to go into scientific detail only need to know that if the models cannot make accurate predictions then they are no better opinions.

    When defenders of the models weasel-out and say they are “projections” not “predictions”, then they must be challenged and asked “So what use are they?” Why should policy-makers enforce laws upon us based on models that are useless. Models whose defenders claim they ‘predicted’ every adverse weather event, yet head for the hills whenever they are pulled-up over their failures?

  4. michael hart says:

    penultimate paragraph last sentence should read “.. no better than opinions.”