Energy & Environment

Increase in CO2 is Not a Cause for Alarm

(As the cap-and-trade legislation [see cover story] drafted by liberal Democratic Representatives Henry Waxman (Calif.) and Ed Markey (Mass.) is running into resistance in Congress in Congress, the Environmental Protection Agency recently took initial steps to regulate greenhouse gas emissions under the Clean Air Act. On April 17, EPA proposed a finding that greenhouse gases “endanger public health and welfare,” which, when finalized, will mean that thousands of sources, including schools, hospitals, churches, nursing homes, and virtually any activity that emits CO2, will be regulated by EPA. The Obama Administration is using this “endangerment” finding to try to blackmail Congress into pass cap-and-trade legislation, arguing that it would be far less damaging to the economy. But many Republicans, and a growing number of Democrats, oppose both options, and are considering legislation that would prevent EPA from regulating greenhouse gases.)  

In testimony before the U.S. Senate Environment and Public Works Committee on Feb. 25, 2009, highly respected scientist William Happer explained why he rejects the hysteria over CO2 and why he believes that “the increase of CO2 is not a cause for alarm and will be good for mankind.” This article is excerpted from that testimony.  

I am not a climatologist, but I don’t think any of the other witnesses are either. I do work in the related field of atomic, molecular and optical physics. I have spent my professional life studying the interactions of visible and infrared radiation with gases — one of the main physical phenomena behind the greenhouse effect. I have published over 200 papers in peer-reviewed scientific journals. I am a member of a number of professional organizations, including the American Physical Society and the National Academy of Sciences.… I also served as the director of Energy Research at the Department of Energy (DOE) from 1990 to 1993, where I supervised all of DOE’s work on climate change.

I have come here today as a concerned citizen to express my personal views, and those of many like me, about U.S. climate-change policy. These are not official views of my main employer, Princeton University, nor of any other organization with which I am associated.

Let me state clearly where I probably agree with the other witnesses: We have been in a period of global warming over the past 200 years, but there have been several periods, like the last ten years, when the warming has ceased and there have even been periods of substantial cooling, as from 1940 to 1970. Atmospheric concentrations of carbon dioxide (CO2) have increased from about 280 to 380 parts per million (ppm) over past 100 years. The combustion of fossil fuels, coal, oil and natural gas, has contributed to the increase of CO2 in the atmosphere. And finally, increasing concentrations of CO2 in the atmosphere will cause the Earth’s surface to warm. The key question is: Will the net effect of the warming, and any other effects of the CO2, be good or bad for humanity?

I believe that the increase of CO2 is not a cause for alarm and will be good for mankind. I predict that future historians will look back on this period much as we now view the period just before the passage of the 18th Amendment to the U.S. Constitution to prohibit “the manufacturing, sale or transportation of intoxicating liquors.”

At the time, the 18th amendment seemed to be exactly the right thing to do. Who wanted to be in league with demon rum? It was the 1917 version of saving the planet. There were many thoughtful people who thought that prohibition might do more harm than good. But they were completely outmatched by the movement, whose motives and methods had much in common with the movement to stop climate change. Prohibition was a mistake, and our country has probably still not fully recovered from the damage it did. Institutions like organized crime got their start in that era. Drastic limitations on CO2 are likely to damage our country in analogous ways.

But what about the frightening consequences of increasing levels of CO2 that we keep hearing about? In a word, they are wildly exaggerated, just as the purported benefits of prohibition were wildly exaggerated. Let me turn now to the science and try to explain why I and many scientists like me are not alarmed by increasing levels of CO2.

The Earth’s climate really is strongly affected by the greenhouse effect, although the physics is not the same as that which makes real, glassed-in greenhouses work. Without greenhouse warming, the earth would be much too cold to sustain its current abundance of life. However, at least 90% of greenhouse warming is due to water vapor and clouds. Carbon dioxide is a bit player. There is little argument in the scientific community that a direct effect of doubling the CO2 concentration will be a small increase of the earth’s temperature—on the order of one degree.

Additional increments of CO2 will cause relatively less direct warming because we already have so much CO2 in the atmosphere that it has blocked most of the infrared radiation that it can. It is like putting an additional ski hat on your head when you already have a nice warm one below it, but you are wearing only a windbreaker. To really get warmer, you need to add a warmer jacket. The Intergovernmental Panel on Climate Change (IPCC) thinks that this extra jacket is water vapor and clouds.

Since most of the greenhouse effect for the earth is due to water vapor and clouds, added CO2 must substantially increase water’s contribution to lead to the frightening scenarios that are bandied about. The buzz word here is that there is “positive feedback.” With each passing year, experimental observations further undermine the claim of a large positive feedback from water. In fact, observations suggest that the feedback is close to zero and may even be negative. That is, water vapor and clouds may actually diminish the already small global warming expected from CO2, not amplify it.

The evidence here comes from satellite measurements of infrared radiation escaping from the Earth into outer space, from measurements of sunlight reflected from clouds and from measurements of the temperature the Earth’s surface or of the troposphere, the roughly 10 km thick layer of the atmosphere above the earth’s surface that is filled with churning air and clouds, heated from below at the Earth’s surface, and cooled at the top by radiation into space.

The climate is warming and CO2 is increasing. Doesn’t this prove that CO2 is causing global warming through the greenhouse effect? No, the current warming period began about 1800 at the end of the little ice age, long before there was an appreciable increase of CO2. There have been similar and even larger warmings several times in the 10,000 years since the end of the last ice age. These earlier warmings clearly had nothing to do with the combustion of fossil fuels. The current warming also seems to be due mostly to natural causes, not to increasing levels of carbon dioxide. Over the past ten years there has been no global warming, and in fact a slight cooling. This is not at all what was predicted by the IPCC models.

Farms in Greenland

The climate has changed many times in the past with no help by mankind. Recall that the Romans grew grapes in Britain around the year 100, and Viking settlers prospered on small farms in Greenland for several centuries during the Medieval Climate Optimum around 1100.… The existence of climate variability in the past has long been an embarrassment to those who claim that all climate change is due to man and that man can control it.

When I was a schoolboy, my textbooks on earth science showed a prominent “Medieval warm period” at the time the Vikings settled Greenland, followed by a vicious “little ice age” that drove them out. So I was very surprised when I first saw the celebrated “hockey stick curve,” in the Third Assessment Report of the IPCC. I could hardly believe my eyes. Both the little ice age and the Medieval warm period were gone, and the newly revised temperature of the world since the year 1000 had suddenly become absolutely flat until the last hundred years when it shot up like the blade on a hockey stick. This was far from an obscure detail, and the hockey stick was trumpeted around the world as evidence that the end was near. We now know that the hockey stick has nothing to do with reality but was the result of incorrect handling of proxy temperature records and incorrect statistical analysis.

There really was a little ice age and there really was a medieval warm period that was as warm or warmer than today. I bring up the hockey stick as a particularly clear example that the IPCC summaries for policy makers are not dispassionate statements of the facts of climate change. It is a shame, because many of the IPCC chapters are quite good, but the IPCC has made no serious attempt to model the natural variations of the Earth’s temperature in the past. Whatever caused these large past variations, it was not due to people burning coal and oil. If you can’t model the past, where you know the answer pretty well, how can you model the future?

Gore’s CO2 Errors

Many of us are aware that we are living in an ice age, where we have hundred-thousand-year intervals of big continental glaciers that cover much of the land area of the Northern hemisphere, interspersed with relative short interglacial intervals like the one we are living in now. By looking at ice cores from the Greenland and Antarctic ice sheets, one can estimate past temperatures and atmospheric concentrations of CO2. Al Gore likes to display graphs of temperature and CO2 concentrations over the past million years or so, showing that when CO2 rises, the temperature also rises. Doesn’t this prove that the temperature is driven by CO2? Absolutely not! If you look carefully at these records, you find that first the temperature goes up, and then the CO2 concentration of the atmosphere goes up.

There is a delay between a temperature increase and a CO2 increase of about 800 years. This casts serious doubt on CO2 as a climate driver because of the fundamental concept of causality. A cause must precede its effect. … Sure, temperature and gas burning are correlated, just like temperature and atmospheric levels of CO2. But the thing that changes first is the cause. In the case of the ice cores, the cause of increased CO2 is almost certainly the warming of the oceans. The oceans release dissolved CO2 when they warm up, just like a glass of beer rapidly goes flat in a warm room. If not CO2, then what really causes the warming at the end of the cold periods of ice ages? A great question and one of the reasons I strongly support research in climate.

CO2 Not Pollutant

I keep hearing about the “pollutant CO2,” or about “poisoning the atmosphere” with CO2, or about minimizing our “carbon footprint.” This brings to mind another Orwellian pronouncement that is worth pondering: “But if thought corrupts language, language can also corrupt thought.” CO2 is not a pollutant and it is not a poison and we should not corrupt the English language by depriving “pollutant” and “poison” of their original meaning. Our exhaled breath contains about 4% CO2. That is 40,000 parts per million, or about 100 times the current atmospheric concentration. CO2 is absolutely essential for life on earth. Commercial greenhouse operators often use CO2 as a fertilizer to improve the health and growth rate of their plants. Plants and our own primate ancestors evolved when the levels of atmospheric CO2 were about 1,000 ppm, a level that we will probably not reach by burning fossil fuels, and far above our current level of about 380 ppm.

Few adverse effects are observed at even higher levels. We are all aware that “the green revolution” has increased crop yields around the world. Part of this wonderful development is due to improved crop varieties, better use of mineral fertilizers, herbicides, etc. But no small part of the yield improvement has come from increased atmospheric levels of CO2. Plants photosynthesize more carbohydrates when they have more CO2. Plants are also more drought-tolerant with more CO2, because they need not “inhale” as much air to get the CO2 needed for photosynthesis. At the same time, the plants need not “exhale” as much water vapor when they are using air enriched in CO2. Plants decrease the number of stomata or air pores on their leaf surfaces in response to increasing atmospheric levels of CO2. They are adapted to changing CO2 levels and they prefer higher levels than those we have at present.

If we really were to decrease our current level of CO2 of around 400 ppm to the 270 ppm that prevailed a few hundred years ago, we would lose some of the benefits of the green revolution. Crop yields will continue to increase as CO2 levels go up, since we are far from the optimum levels for plant growth. Commercial greenhouse operators are advised to add enough CO2 to maintain about 1000 ppm around their plants. Indeed, economic studies like those of Dr. Robert Mendelsohn at Yale University project that moderate warming is an overall benefit to mankind because of higher agricultural yields and many other reasons.…

That we are (or were) living at the best of all CO2 concentrations seems to be a tacit assumption of the IPCC executive summaries for policy makers.

Enormous effort and imagination have gone into showing that increasing concentrations of CO2 will be catastrophic, cities will be flooded by sea-level rises that are ten or more times bigger than even IPCC predicts, there will be mass extinctions of species, billions of people will die, tipping points will render the planet a desert. A few months ago I read that global warming will soon bring on a devastating epidemic of kidney stones. If you write down all the ills attributed to global warming you fill up a very thick book.

Tropical Disease Nonsense

Much is made about tropical diseases like malaria and yellow fever devastating the populations of temperate climates because of the burning of fossil fuels and the subsequent warming of the earth. Many people who actually work with tropical diseases, notably Dr. Paul Reiter, a specialist on tropical diseases, have pointed out how silly all of this is.…
Controlling tropical diseases and many other diseases has little to do with temperature, and everything to do with curtailing the factors that cause the spread — notably mosquitoes in the case of malaria and yellow fever.

Many of the frightening scenarios about global warming come from large computer calculations — “general circulation models” — that try to mimic the behavior of the Earth’s climate as more CO2 is added to the atmosphere. It is true that climate models use increasingly capable and increasingly expensive computers. But their predictions have not been very good. For example, none of them predicted the lack of warming that we have experienced during the past ten years. All the models assume the water feedback is positive, while satellite observations suggest that the feedback is zero or negative.…

This brings up the frequent assertion that there is a consensus behind the idea that there is an impending disaster from climate change, and that it may already be too late to avert this catastrophe, even if we stop burning fossil fuels now. We are told that only a few flat-earthers still have any doubt about the calamitous effects of continued CO2 emissions. There are a number of answers to this assertion.

First, what is correct in science is not determined by consensus but by experiment and observations. Historically, the consensus is often wrong.… Secondly, I do not think there is a consensus about an impending climate crisis. I personally certainly don’t believe we are facing a crisis unless we create one for ourselves. Many others, wiser than I am, share my view. The number of those with the courage to speak out is growing. There may be an illusion of consensus. Like the temperance movement one hundred years ago the climate-catastrophe movement has enlisted the mass media, the leadership of scientific societies, the trustees of charitable foundations, and many other influential people to their cause.

Strong-Arming Skeptics

Just as editorials used to fulminate about the slippery path to hell behind the tavern door, hysterical op-eds lecture us today about the impending end of the planet and the need to stop climate change with bold political action. Many distinguished scientific journals now have editors who further the agenda of climate-change alarmism. Research papers with scientific findings contrary to the dogma of climate calamity are rejected by reviewers, many of whom fear that their research funding will be cut if any doubt is cast on the coming climate catastrophe..… Certainly, it is a bit unnerving to read statements of Dr. James Hansen in the Congressional Record that climate skeptics are guilty of “high crimes against humanity and nature.”

Even elementary school teachers and writers of children’s books are enlisted to terrify our children and to promote the idea of impending climate doom. Having observed the education of many children, including my own, I am not sure how effective the effort will be. Many children seem to do just the opposite of what they are taught. Nevertheless, children should not be force-fed propaganda, masquerading as science. Many of you may know that in 2007 a British Court ruled that if Al Gore’s book, An Inconvenient Truth, was used in public schools, the children had to be told of 11 particularly troubling inaccuracies. You can easily find a list of the inaccuracies on the internet, but I will mention one. The court ruled that it was not possible to attribute hurricane Katrina to CO2. Indeed, had we taken a few of the many billions of dollars we have been spending on climate change research and propaganda and fixed the dikes and pumps around New Orleans, most of the damage from Hurricane Katrina could have been avoided.

The sea level is indeed rising, just as it has for the past 20,000 years since the end of the last ice age. Fairly accurate measurements of sea level have been available since about 1800. These measurements show no sign of any acceleration. The rising sea level can be a serious local problem for heavily populated, low-lying areas like New Orleans, where land subsidence compounds the problem. But to think that limiting CO2 emissions will stop sea level rise is a dangerous illusion. It is also possible that the warming seas around Antarctica will cause more snowfall over the continent and will counteract the sea-level rise. In any case, the rising sea level is a problem that needs quick local action for locations like New Orleans rather than slow action globally.

In closing, let me say again that we should provide adequate support to the many brilliant scientists, some at my own institution of Princeton University, who are trying to better understand the Earth’s climate, now, in the past, and what it may be in the future. I regret that the climate-change issue has become confused with serious problems like secure energy supplies, protecting our environment, and figuring out where future generations will get energy supplies after we have burned all the fossil fuel we can find. We should not confuse these laudable goals with hysterics about carbon footprints. For example, when weighing pluses and minuses of the continued or increased use of coal, the negative issue should not be increased atmospheric CO2, which is probably good for mankind. We should focus on real issues like damage to the land and waterways by strip mining, inadequate remediation, hazards to miners, the release of real pollutants and poisons like mercury, other heavy metals, organic carcinogens, etc. Life is about making decisions and decisions are about trade-offs. Congress can choose to promote investment in technology that addresses real problems and scientific research that will let us cope with real problems more efficiently. Or they can act on unreasonable fears and suppress energy use, economic growth and the benefits that come, from the creation of national wealth.

William Happer is the Cyrus Fogg Brackett Professor of Physics at Princeton University.  


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