Increasing CO2 Good for Mankind
Statement of Dr. William Happer, Ph.D., Cyrus Fogg Brackett Professor of Physics, Princeton University
Before the U.S. Senate Environment and Public Works Committee, Senator Barbara Boxer, Chair
February 25, 2009
Full text [here]
Selected excerpts:
Madam Chairman and members, thank you for the opportunity to appear before the Committee on Environment and Public Works to testify on Climate Change. …
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 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. …
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. …
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. …
But 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.
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. …
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.
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 1000 ppm, a level that we will probably not reach by burning fossil fuels, and far above our current level of about 380 ppm. We try to keep CO2 levels in our US Navy submarines no higher than 8,000 parts per million, about 20 time current atmospheric levels. 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. …
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.
Modelers have been wrong before. One of the most famous modeling disputes involved the physicist William Thompson, later Lord Kelvin, and the naturalist Charles Darwin. Lord Kelvin was a great believer in models and differential equations. Charles Darwin was not particularly facile with mathematics, but he took observations very seriously. For evolution to produce the variety of living and fossil species that Darwin had observed, the earth needed to have spent hundreds of millions of years with conditions not very different from now. With his mathematical models, Kelvin rather pompously demonstrated that the earth must have been a hellish ball of molten rock only a few tens of millions of years ago, and that the sun could not have been shining for more than about 30 million years. Kelvin was actually modeling what he thought was global and solar cooling. I am sorry to say that a majority of his fellow physicists supported Kelvin. Poor Darwin removed any reference to the age of the earth in later editions of the “Origin of the Species.” But Darwin was right the first time, and Kelvin was wrong. Kelvin thought he knew everything but he did not know about the atomic nucleus, radioactivity and nuclear reactions, all of which invalidated his elegant modeling calculations.
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, and I just mentioned the incorrect consensus of modelers about the age of the earth and the sun. During the yellow fever epidemic of 1793 in Philadelphia the medical consensus was that you could cure almost anything by bleeding the patient. Benjamin Rush, George Washington’s Surgeon General during the War of Independence, and a brave man, stayed in Philadelphia throughout the yellow fever epidemic. He worked tirelessly to save the stricken by bleeding them, the consensus treatment of the day. A few cautious observers noticed that you were more likely to survive the yellow fever without the services of the great man. But Dr. Rush had plenty of high level-friends and he was backed up by the self-evident consensus, so he went ahead with his ministrations. In summary, a 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, as Benjamin Rush did by bleeding his patients. 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. Just as editorials used to fulminate about the slippery path to hell behind the tavern door, hysterical op-ed’s 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. Speaking of the Romans, then invading Scotland in the year 83, the great Scottish chieftain Calgacus is quoted as saying “They make a desert and call it peace.” If you have the power to stifle dissent, you can indeed create the illusion of peace or consensus. The Romans have made impressive inroads into climate science. 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.” …
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 eleven 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 the 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. The 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.
