Is the Man-Made Climate Change Debate Really Over?

Written by Dom Armentano


Climate change enthusiasts are convinced that man-made global warming poses a near-term environmental disaster. Yet gloom-and-doom forecasts about the fate of the Earth are hardly new, and few have proven accurate.

In 1798 the Rev. Thomas Malthus predicted that mass starvation would strike England in the 19th century because population growth would inevitably overwhelm food production. It didn’t happen.

Or recall the dire predictions by experts in the 1970s that the world was running out of oil and that prices would skyrocket and stay high for decades.

These views were supported by analyses from the CIA and a boatload of geologists who believed in the so-called “peak oil” theory.

But the experts were wrong. Adjusted for inflation, a barrel of crude oil today is cheaper than it was in 1980, which is arguably one of the most pro-consumer developments in recent economic history.

And now we are told that the world is on the brink of environmental disaster due to man-made global warming.

The conventional wisdom, repeated endlessly in the popular press, is that the Earth is heating dangerously because we burn fossil fuels and that this will generate devastating droughts, fires, floods, and rising ocean levels. (The oceans are currently rising by about one-eighth of an inch per year).

In response, several prominent politicians have developed multitrillion-dollar plans to “do something.” Those who question those plans, or the theory that temperature increases are man-made, are often smeared as immoral or antiscience.

Yet there is really only one policy-relevant question in the entire climate-change debate: does the increased use of fossil fuels—and the consequent increase in carbon dioxide emissions—contribute significantly to the increase in the Earth’s surface temperature?

The scientific evidence on warming is reasonably clear: since 1880, the atmospheric temperature has increased slightly more than 1 degree Celsius.

Over those many decades, there have been periods of warming, periods of cooling, periods where no major changes occurred, and more recently, a relatively modest but sustained period of warming. No real debate here.

But can this recent warming be reasonably correlated with increased fossil-fuel use? After all, C02 is a relatively minor greenhouse gas (0.041 percent by volume), and any statistical association of specific levels of carbon emissions with specific temperature changes historically has not been compelling.

For example, while CO2 emissions have steadily increased for many decades (much of it from expanding industrial activity in India and China), the Earth’s temperature, though trending upward, has varied markedly.

More specifically, while CO2 growth rates have been almost five times greater since World War II than before, the average annual temperature increase since 1945 has been roughly the same as it was before 1945.

All of this would imply that increased CO2 levels may not be the sole (or perhaps even the primary) factor driving changes in global temperatures.

Yet if CO2 is not the primary cause of temperature change, then the entire economic and political case for carbon taxes and other regulations on CO2 emissions is severely weakened.

Why should we increase the price of energy generated from oil and natural gas (let alone consider the multitrillion-dollar costs of any Green New Deal) if reducing emissions in the United States (or even the rate of emissions) would produce no discernable net benefit to society?

After all, one thing is certain in this entire debate. Any important restriction on the use of fossil fuels would raise the price of almost everything and hurt low-income families the most, despite any political promises to the contrary.

Some of us are old enough to remember the major print media (Time, Newsweek, etc.) scare stories concerning global cooling in the early 1970s.

We were all going to freeze in the dark unless the government did something about the coming mini-ice age. But cooler heads prevailed, and we didn’t rush to judgment with massive environmental regulation—which would have been a disaster.

Let’s take a breath and adopt that same cautious approach with respect to the current controversy.

Dom Armentano is a research fellow at the Independent Institute, professor emeritus of economics at the University of Hartford, and author of Antitrust and Monopoly (Independent Institute).


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Comments (6)

  • Avatar

    Denis Ables


    It’s not difficult to show that CO2, although increasing, has little to do with our current warming. It’s also easy to show that the MWP was global and at least as warm as it is now, and this can be demonstrated without controversial models or dubious statistical machinations. Alarmists, rather than taking advantage of earlier global warming information, have, for unexplained reasons, based their computer projections on a cherry-picked short-term correlation between rising CO2 and rising temperature from 1975 to the 2000s. (There was conflicting data before and afterwards: a cooling between 1945 and 1975 and the IPCC admission there was a temperature “hiatus” in the 2000s.)

    The only other indication favoring CO2 as the culprit causing warming is that when CO2 is added to a closed container, the container temperature increases somewhat. However, the open atmosphere is hardly a closed container. Satellites detect heat escaping to space and closed containers do not experience planetary-level feedbacks.

    The proponents of anthropogenic-caused global warming invariably DENY that the Medieval Warming Period (MWP, 1,000 years ago) was global and at least as warm as now. The alarmists acknowledge only that Europe experienced the MWP. (They had no choice – climate in that region is too well documented!) Alarmists apparently take this unjustifiable position because their computer models cannot explain any of the earlier global warmings. Their computer models depend heavily on increasing CO2 level, even more so on yet another ASSUMPTION – that water vapor feedback is the actual culprit, causing 2 to 3 times the temperature increase supposedly brought on by the increase in CO2.

    The global temperature increase during the MWP, as well as during the earlier global warmings, could not have been influenced by CO2 because there was no increase in CO2. The problem for alarmists is that it becomes obvious that our current warming (such as it is) might also be due to NATURAL climate variation. That, of course, conflicts with Mann’s hockey stick graph. Mann recently lost a suit he brought against Dr. Tim Ball years ago. Ball had apparently implied that at least some of Mann’s work was fraudulent. Mann succeeded in delaying dismissal of that suit by agreeing to provide his “work”, on or before the revised termination date, but apparently did not supply his data by the extended date. Man has been ordered to pay Ball’s $700k in legal expenses. (How does this suit differ from a legal harassment suit?) Mann claims his some of his work is proprietary even though several other folks have apparently claimed that they were able to replicate his work, so what’s that about?

    Without bothering to further discuss the dubious (and controversial) process employed by Mann to generate his hockey stick graph it is easy to show (and easy to understand) that the MWP was indeed global and at least as warm as now. While that proves nothing directly about the cause of our current warming (such as it is) it speaks loudly about the credibility of the folks who use models rather than global data and who continue to DENY that the MWP was global and at least as warm as now. The link below provides, among other things, an MWP global study. It also addresses the various alarmist “talking points”.

    The question remains. Why in the world did the alarmists choose CO2 as the culprit when there is no evidence that CO2, a trace gas, has ever, even over geologic periods when CO2 was 10 to 20 times higher, had any impact on our planet’s temperature? There was obviously some uncertainty. There was almost immediate skepticism voiced by credible researchers about Mann’s process. There were also existing peer-reviewed studies. Phil Jones, one of the prominent early alarmist players, publicly stated that if the MWP was global and as warm as now, then that was a “different ballgame”. Nonetheless, alarmists decided instead to blame human activity and that pretty much leads to denying that the MWP was global and at least as warm as now.

    It’s obvious now, if not then, that a more thorough investigation of the earlier global warmings, particularly the MWP, was needed before resorting to pure speculation about CO2.

    Some time ago Henrik Svensmark, a Danish physicist and his associates, offered a theory which makes use of, and explains, the historical data. Svensmark’s theory proposes that sun activity modulates the level of a rather steady stream of cosmic rays intent on penetrating the lower atmosphere. (CERN certified some time ago that cosmic rays may influence the level of cloud cover.) Until very recently we have, for some time, been experiencing a high level of sun activity. During such active periods the level of cloud coverage drops because fewer cosmic rays can penetrate the solar wind barrier. With less cloud cover more sun energy reaches the earth surface so the earth becomes warmer. However, a very low level of sun activity is now underway. If the sun remains inactive for a significant period, Svensmark’s theory predicts more cloud cover, hence a cooler earth. CO2 plays no part in Svensmark’s theory.

    At this stage of the game, whether or not Svensmark’s theory holds up, it appears that serious attention needs to be directed to historical data. If that cannot even be explained then speculation about the future is unlikely to be fruitful. Since CO2 increase was the only possible link between human activity and global warming, it appears that human activity (apart from its impact on Urban Heat Islands) plays no part in global warming. Increasing CO2 should be of more concern to such disciplines as botanists and health researchers rather than climatologists.

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      Michael Mann’s hockey stick graph CAN NOT be replicated because he refuses to provide the data which invalidates his theory.

      In fact the other 2 aspects of the AGW have been also invalidated. The rings of a single spruce tree is not evidence of global warming and there is no evidence that co2 rises before the temperature.

      A close examination of the IPCC’s models have revealed the General Circulation Model is inadequate to model the climate because they over estimate co2 sensitivity and completely ignore the impact of 24 other systems which explains why their predictions have been extremely inaccurate.

      Why our politicians and bureaucrats have blindly accepted the recommendations of the IPPC escapes me.

      Our best hope is to educate our local, state and national politicians and bureaucrats directly.

  • Avatar

    Andy Rowlands


    I would also like to think cooler heads and sensible policies will result, but I fear they will not. Governments have either been totally taken in by the climate scam, or are willing participants. Either way, I cannot see them deviating from their course, and the only result will be significantly reduced standards of living for the populace, frequent and permanent power cuts, and shortages of everything.

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      Indeed, as is said:
      ‘ Once they lie, they must continue to lie’.

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    The following is a smidgeon of succinct pertinence from this article that I have not encountered previously.

    “More specifically, while CO2 growth rates have been almost five times greater since World War II than before, the average annual temperature increase (during periods of temperature increase) since 1945 has been roughly the same as it was before 1945.

    I have taken the liberty of adding the pedantic addendum in brackets.


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