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Energy, Carbon Dioxide and Earth's Future
Pursuing the Prudent Path

C. D. Idso and K. E. Idso
Center for the Study of Carbon Dioxide and Global Change

Cheap energy fuels the economic engine that is reducing poverty around the world at an unprecedented rate; yet the fossil fuels from which the lion's share of that energy is derived are claimed by some to be major threats to the environment.  Even though energy from coal, gas and oil makes possible the processes that sustain the wonderful standard of living with which much of today's world is blessed, these fuels are often castigated as being inimical to our future well-being, due to their presumed propensity to enhance the planet's natural greenhouse effect and elevate global temperatures to dangerously high levels.  But is a little rise in the air's CO2 content really that big a problem?

CO2, a tiny but essential component of the atmosphere, wields nowhere near the climatic power often ascribed to it.  As presently constituted, earth's atmosphere contains only 370 parts per million (ppm) of the colorless and odorless gas we call carbon dioxide.  That's just a little over three-and-a-half one-hundredth of one percent, i.e., 0.037%.  Even if its concentration were tripled, carbon dioxide would still comprise only a little over a tenth of a percent of the air we breathe, which is far less than what wafted through earth's atmosphere eons ago, when the planet was a virtual garden place.  Nevertheless, and as illogical as it would seem (and truly is!), a mere doubling of this minuscule amount of CO2 is perennially predicted to produce a suite of dire environmental consequences, including dangerous global warming, catastrophic sea level rise, reduced agricultural output, ravaged natural ecosystems and dramatic increases in extreme weather events, such as droughts, floods and hurricanes.

Inadequate computer climate models are the sources of multiple environmental misperceptions.  As strange as it may seem, the frightening prophecies of doom and gloom that are regularly served up to society on a wide variety of environmental topics by an all-too-happy-to-oblige media are invariably derived from a single source of information: the ever-evolving computer climate models that presume to reduce all of the physical, chemical and biological processes that combine to determine the state of earth's climate to a set of mathematical equations out of which the field's practitioners claim to be able to squeeze a reliable forecast of a host of unpalatable things to come.  But does any reasonable person think that we even know what all of those complex and interacting processes are?  Or that we can reduce them to such a neat and manageable package?

Apparently, some people answer these questions in the affirmative, especially those who seek to remake the world into a political structure more to their liking.  And they are willing to gamble all that humanity has achieved in the way of modern economic progress on their belief - for we hope it is nothing more sinister - that the admittedly imperfect climate models are basically correct in what they are telling us about future weather.  Throwing caution to the wind, therefore, they would have us embark upon a retrogressive policy that would deny us the many known benefits that we and the rest of the biosphere could readily reap from continued and even expanded usage of coal, gas and oil as our primary sources of economically-important, safe and reliable energy generation.

Science reveals the difference between biological fact and climatic speculation.  Why are we so confident that what many people accept as absolute truth, i.e., that the ongoing rise in the air's CO2 content will be detrimental to the biosphere, is actually a hundred and eighty degrees out of phase with reality?  Because science tells us that putting more CO2 in the air would actually be good for the planet, and because even the best climate models are manifestly incapable of delivering what we require of them, i.e., correct climate forecasts.

In the case of the biospheric benefits of atmospheric CO2 enrichment, it is an indisputable fact that carbon dioxide is one of the basic building blocks of life, comprising the major "food" of nearly all plants on earth.  With more CO2 in the air, literally thousands of experiments have proven, beyond any doubt, that plants grow bigger and better in almost every conceivable way, and they do it more efficiently, with respect to the availability of important natural resources, and more effectively, in the face of various environmental constraints.  And when plants benefit, so do all of the animals that depend upon them for their sustenance, including us humans.  Without question, therefore, CO2 is the elixir of life, the rock-bottom foundation of nearly all that lives on the planet, be it in the ground, in the oceans, or in the air.

In the case of the climate models, on the other hand, all one needs to do to discover their inadequacies is compare their predictions with the reality of the recent past.  Even though the world has warmed substantially during the period of the industrialization of the planet - due to who-knows-what (for it cannot be proven that the contemporaneous rise in atmospheric CO2 was responsible for the warming) - none of the environmental catastrophes that are supposed to accompany that warming, according to the climate models, has come to pass.

History and simple logic reveal climate model predictions of CO2-induced global warming to be untenable.  The fact that there have been no significant increases in either droughts, floods or hurricanes over the past two centuries of modest global warming poses an important question.  What should be easier to predict: the effects of global warming on extreme weather events or the effects of elevated atmospheric CO2 on global temperature?  The first part of this question should, in principle, be answerable; for it is well defined in terms of the small number of known factors likely to play a role in linking the independent variable (global warming) with the specified weather phenomena (droughts, floods and hurricanes).  The latter part of the question, on the other hand, is ill-defined and possibly even unanswerable; for there are many factors - physical, chemical and biological - that could well be involved in linking CO2 (or causing it not to be linked) with global temperature.

If, then, the climate models cannot correctly predict what should be relatively easy for them to correctly predict (the effect of global warming on extreme weather events), why should we believe what they say about something infinitely more complex (the effect of a rise in the air's CO2 content on mean global air temperature)?  Clearly, we should pay the models no heed in the matter of future climate - especially in terms of predictions based on the behavior of a non-meteorological parameter (CO2) - until they can reproduce the climate of the past - based on the behavior of one of the most basic of all true meteorological parameters (temperature).  And even when (or if!) the models solve this part of the problem, we should still reserve judgment on their forecasts of global warming; for there will yet be a vast gulf between where they will be at that time and where they will have to go to be able to meet the much greater challenge to which they aspire.

Proper use of the precautionary principle suggests we stay the course of non-atmospheric intervention.  In view of these observations, what does the precautionary principle tell us about programs designed to curtail the use of fossil fuels?  It says, most clearly, "Don't bite the hand that feeds you," especially when there is absolutely no evidence that there is anything but blessings that come from that hand.  Indeed, since CO2 is what sustains the biosphere and makes life possible for us, it would be an affront to reason to do anything else, and especially to impose draconian measures that would bring severe economic hardship upon nearly all the people of the world.

In summary, let well enough alone.  The Industrial Revolution has been a tremendous boon to humanity, as it has lifted large numbers of our kind from poverty to prosperity.  It has also helped the rest of the biosphere - and thereby us once again - via the powerful aerial fertilization effect of the carbon dioxide that has gone into the atmosphere as a consequence of the burning of fossil fuels.  Indeed, it's been win, win, win for all of life; and if there's ever been a recipe for success, this is it.  Therefore, in invoking the precautionary principle one last time, our advice to policy makers who may be tempted to embrace Kyoto-type programs is simply this: Don't mess with success!  Fossil-fuel-derived energy has served us well in the past, and it will serve us well in the future.  Letting nature and the market place take their unimpeded courses is the path of prudence that will bring unbounded prosperity to generations yet unborn.

Supporting references.  This brief was written in 1999.  References to the voluminous scientific literature that supports the many factual statements of this position paper may be found on our website - - which we update weekly.