What others are saying about Global Warming: Alarmists, Skeptics and Deniers
“Global Warming: Alarmists, Skeptics and Deniers is a refreshing read on a topic of great societal importance; refreshing because, unlike many books published on this subject, the authors of this work evaluate key predictions and controversies of the global warming debate using logic and science. Most readers will appreciate the book’s arrangement. Each chapter presents a series of questions and answers that revolve around a central theme. The book is well written and easy to be understood by those with little knowledge or scientific background in the global warming debate.”—Dr. Craig D. Idso, founder and chairman of the board of the Center for the Study of Carbon Dioxide and Global Change.
“Dr. G Dedrick Robinson comments in his Prologue that: 'As a geologist, I knew that climate has always changed,' and therein lies the core message of this informative book. Writing in an easily accessible style for all readers, and using Socratic dialogue, Robinson leads us systematically through the simple science information that is needed to answer the question, 'Are human carbon dioxide emissions causing dangerous global warming?' And the more surprised you are that the answer to this question is 'no,' then the more you need to read this excellent book.”—Professor Robert M. Carter, Marine Geophysical Laboratory, James Cook University, Australia
“GLOBAL WARMING: ALARMISTS, SKEPTICS AND DENIERS is an excellent, accessible handbook for those interested in the science of global warming. Skeptics have long maintained that the bulk of the science is on their side. Anyone who reads Dr. Robinson's book with an open mind will find it hard not to agree.”—Iain Murray, author of The Really Inconvenient Truths “GLOBAL WARMING: ALARMISTS, SKEPTICS AND DENIERS is an excellent analysis of the problems of climate science from the perspective of a veteran geologist. Particularly useful are Dr. Robinson's discussion of why climate models often fail, and how today's climate changes, when compared to those of the geological past, are clearly seen as well within natural variation. But there is much more science—enough, I'd think, to persuade all but die-hard global-warming believers that a skeptical position is much truer to the climate evidence than alarmism.”—Paul MacRae, author of False Alarm—Global Warming: Facts Versus Fears GLOBAL WARMING: ALARMISTS, SKEPTICS and DENIERS
A Geoscientist looks at the Science of Climate Change
G Dedrick Robinson Ph.D.
Gene D. Robinson III ESQUIRE
Moonshine Cove Publishing, LLC
Books that Beckon
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G Dedrick Robinson Ph.D. recently retired after nearly thirty years as a Professor of Geology at James Madison University in Virginia. He is the author of numerous scientific articles in peer reviewed journals. His background in teaching a wide variety of scientific concepts has uniquely qualified him to discuss difficult scientific concepts in a way that is understandable and interesting to non-scientists. He has studied glaciers in Alaska, volcanic processes in California and Oregon, landslides in North Carolina, flood deposits in Virginia, river processes in Arkansas, zinc deposits in Tennessee, acid mine drainage in Colorado and the conditions which promote the precipitation of manganese oxide coatings on stream alluvium. Dr. Robinson's discussion of climate change and earth history during a public TV program broadcast over a state-wide network was well received. He has spoken at state, regional, national and international geoscience conferences and also has a long record of having successfully taught introductory geology to non-science majors and geology courses to high school earth science teachers.
Contact Dr. Robinson at his web page: gdedrickrobinson.com
Gene D. Robinson III Esquire has been practicing law in Virginia since 2007. Prior to establishing his own law practice, he worked as an associate for a law firm in Fairfax, Virginia from 2007 until 2009. He is a 2007 graduate of the University of Florida, Levin College of Law, where he was the Managing Editor of the Florida Journal of International Law. He worked as a summer associate for Fowler White Burnett, P.A., in Miami, Florida and Time Warner, Inc., in New York City. Gene received an Executive Certificate in Financial Planning from Georgetown University in 2003 and a Bachelor of Science in Speech Communication from James Madison University in 1999. Gene is a Certified Financial Planner™ (CFP)® practitioner and worked as a Wealth Management Advisor for United Bank in Vienna, Virginia before attending law school.
Gene is a proud native of the Shenandoah Valley, Virginia where he served as an infantrymen for six years in the Harrisonburg Company of the 29th Light Infantry Division of the Virginia Army National Guard. He is an active member of the Virginia Bar Association, the Fairfax County Bar Association, the Arlington Bar Association, the Northern Virginia Estate Planning Council and the Northern Virginia Financial Planning Association.
Contact Gene at gene@generobinsonlaw.com or (703) 224-8282.
"It is a capital mistake to theorize before one has data. Unintentionally one begins to twist facts to suit theories, instead of theories to suit facts."—Sherlock Holmes in Sir Author Conan Doyle's A Scandal in Bohemia, 1891
"The tragedy of beautiful theories is that they are often destroyed by ugly facts."—Thomas Huxley (1825-1895)
"By the year 2000 the United Kingdom will be simply a group of impoverished islands inhabited by some 70 million hungry people...If I were a gambler, I would take even money that England will not exist in the year 2000."—Paul Ehrlich, Speech at British Institute for Biology, September 1971
I. THE GREENHOUSE EFFECT AND LIFE
II. CARBON DIOXIDE, GREENHOUSE GASES AND CLIMATE3
III. NORMAL CLIMATE AND CLIMATE CHANGE
IV. EXAMPLES OF CLIMATE CHANGE
VIII. THERMOMETERS, SATELLITES, THE SUN AND COSMIC RAYS
IX. CARBON DIOXIDE AND TEMPERATURE
X. MELTING ICE AND SEA LEVEL RISE
XI. DROUGHTS, FLOODS, EL NINO, WILDFIRES AND HEAT WAVES
XII. SEVERE STORMS AND TROPICAL DISEASES
XIII. THIRTEEN—ACIDIC OCEANS, CORAL BLEACHING AND POLAR BEARS
Dedicated to Professor R.H. Carpenter of the University of Georgia. More than a mentor, Bob Carpenter set me on the right path leading to a successful career in science.
GLOBAL WARMING: ALARMISTS, SKEPTICS AND DENIERS
“Beware of false knowledge: it is more dangerous than ignorance.”
George Bernard Shaw
Man and Superman, 1903
As a young geology instructor in the 1970s, I informed my students of satellite images showing expanding snow cover in North America compared to previous years. I advised them to remain skeptical of the claims then being made in the popular media that this heralded the beginning of the next ice age. A few years later, sensationalist articles about the coming ice age began to be replaced by others saying the earth was growing dangerously warm and we humans were to blame. Why the continuing exaggerations about climate change I wondered, but duly brought this new scare to the attention of my classes with the same caveat as before. I thought it was just more media hype that would fade as quickly as the recent ice age scare. I was wrong. Instead of fading, global warming alarmism increased.
As a geologist and student of earth history, I knew that climate has always changed. Some of the changes had been disastrous, such as the mountains of ice that moved into mid-latitudes during cold phases of the great Pleistocene ice age depopulating millions of square miles. Mostly, however they were just inconsequential changes of a degree or two. The warming we were then experiencing seemed just the latest in a large number minor undulations of climate, not unusual and not unexpected after the frigid temperatures that lasted several hundred years during the recently ended Little Ice Age. Yet, people were on TV acted like climate change was unusual, something that hadn't happened before. Obviously, they had never taken a historical geology course.
For a while, not many people promoted such a view, but the few who did knew how to get attention. And other people were listening. Little did I know a mindset had taken root and started to grow.
A great many people, particularly liberal politicians and most journalists, act as if climate change is odd, strange, extraordinary. Part of this belief system seems to be that yesterday's climate, the preindustrial climate, was ideal, the best of all possible climates, the way nature intended it to be. It was good because it was natural, and we prospered. But now we have strayed far from the natural way, and with our meddling, have upset the balance. We are the reason climate is changing and since it is not natural, it is bad. Nature gave us a stable climate, an ideal climate, but we messed it up
I still have trouble coming to grips with this. Do these people not realize that the preindustrial climate was the Little Ice Age chill? Have they not heard of all the crop failures and famine over large areas of Europe? The glaciers moving down into villages, the frozen rivers, the ice-choked harbors? The year without a summer when snow fell in New England during each summer month? The slow starvation of the Viking villages in Greenland?
My answer is that either they do not know these things because they were never exposed to historical geology, or they ignore it in favor of ideology. They either do not know what came before or don't care.
The new climate alarmism that is an offshoot of the green movement, a movement I understand and in some ways, sympathize with. I became a geologist because I love the grandeur of nature and the outdoors and hate the stifling congestion of cities. However these global warming people turned it all around. Staid and unchanging is not nature's way. The most basic thing about the earth, the first thing geologists learn, is that the only thing constant in nature is change. It can be at such a languid pace that, even over one's full lifetime, it's hard to detect, but it can also be catastrophic. Whether hare or tortoise, geologic change can't be stopped, yet it seemed to me that's what global warming alarmists sought.
Earth history clearly teaches that a static earth has never existed. Our planet is one of the most active bodies in the solar system. All kinds of things constantly change, including weather patterns and climate. Still, natural change does not preclude the possibility that human activities might also cause change. Perhaps, I thought, my own predisposition toward natural change was preventing me from impartially assessing the global warming theory. Maybe powerful evidence supported it. With this in mind, I began to study the scientific literature. To my surprise, I found very little direct evidence that humans were influencing climate. Most of what was offered as evidence was based on the predictions of computer climate models, rather than actual observed data or experimental results. It was as if a weather forecast saying sunny skies for the weekend had been elevated to a greater importance than the rain that actually fell. What was going on here?
I eventually realized that a clash of cultures was underway. Geologists hear the deep past, far before human history, speaking to them. Earth history is measured in hundreds of millions and billions of years. Geologists study ongoing geologic processes not to just gain a better understanding of how the earth works today, but also how it worked in the past. Applying the principle of uniformity, we realize that studying present processes helps us learn how the earth worked in the dim recesses of time. This scientific principle, basic to all the sciences, is that scientific laws and processes that operate today also operated in the past. If this were not true, there could be no science because the result of an experiment might turn out differently today than it did last week, and next week, results might differ from either. If nature were chaotic and irregular, no progress in science would be possible, but, except in the subatomic world of quantum mechanics, nature seems to be orderly and regular.
This principle of uniformity also applies in a different way, a very practical way. Studying what happened in the past has proven to be a reliable guide for what is likely to happen again in the future. We use this principle in numerous ways without realizing it. As a child, we learn to speak by applying it. We learn to avoid certain things, such as a flame, because they were dangerous in the past, and likely still are. We've used this principle a long time. To toss it out would be folly.
For global warming alarmists, instead of the past that is living, it's the future. All their dire warnings are based on computer climate model predictions of things that might or might not happen. These are constructed using the best information we have concerning numerous physical, biological and chemical processes thought to control climate. The predictions can only be as good as the information concerning the various controls that are programmed into the computers. Some of this we think we know well, but others are poorly known, or not known at all.
To geologists like me, something vital is missing in this procedure, what we know happened in the past. A vast amount of this sort of data is available, but computer models use none of it to churn out their predictions. Real information, won at great cost and effort, is ignored in favor of predictions. This is not how science is supposed to work. I learned during my years in graduate school that many things in science are important, but above all is the data. We must honor the data, treat it impartially, let it lead us where it will, allow it to illuminate our way toward better theories. This is the only path that will lead to the light of real knowledge, real progress. This new method of science elevates computer predictions above real data. If the data doesn't agree with the computer forecast, then something must be wrong with the data. Better check it again and find out what's wrong.
Along with my discovery that a paucity of evidence supporting global warming was being hyped and stretched almost beyond belief came the realization that studies running counter to the theory were being ignored. Even worse, an entire group of scientists were not being heard, geologists, the very people who have the most knowledge about earth history. The science with the knowledge that should be most helpful in predicting future trends in climate was being ignored. Meteorologists, climatologists, physicists, chemists, biologists, even economists and politicians were making their view known, but where were the geologists?
I finally decided that this oversight needed correcting. This book is the result.
My goal in writing it is to summarize the science of global warming in a way that is understandable to ordinary people. For those desirous of learning more, references to cited peer-reviewed articles are provided. Throughout, I take a geologic point of view, intentionally elevating data above predictions and forecasts, for this is what has made the scientific method so successful in advancing the human condition. I do not discuss the politics of global warming, the economics, the merits of any particular policy direction or any point of view intentionally meant to favor one political party over another, whether liberal or conservative. Plenty of other books cover these topics.
There might be those who say I have failed at one or more of my objectives because they do not like what I say, while others might recommend the book because they do like my viewpoint. This is the unfortunate result of turning an important scientific question into a political piñata. Science and politics mix even worse than oil and water. Each needs to be kept in its cage completely isolated from the other. This is perhaps the most important lesson of the entire global warming controversy. It is in everyone's interest to try to keep it from happening again.
CHAPTER ONE—THE GREENHOUSE EFFECT AND LIFE
Isn't it true greenhouse gases in the atmosphere are causing the earth to heat dangerously?
Well, certain gases in the atmosphere do produce what's popularly known as the greenhouse effect, but the term is misleading because these gases don't work like the glass in a greenhouse and they are not the source of the earth's heat. They're also far more beneficial than dangerous. Before explaining in more detail, some background will be useful.
The nineteenth century Irish physicist John Tyndall is often given the credit for discovering the greenhouse effect. Although not literally true because the existence of gases in the atmosphere producing such an effect was already widely suspected at the time, Tyndall did perform a series of measurements in 1859 which established the existence of such an effect and quantified it. His work determined the capacity of the various gases which compose the atmosphere, including nitrogen, oxygen, carbon dioxide, ozone, water vapor and various minor gases, to absorb infrared energy, or heat.
Recalling high school science, light, the visible portion of the electromagnetic spectrum, lies between the longer wavelength and less energetic infrared, and the more energetic ultraviolet, shorter wavelengths which cause sunburn. The greatest portion of the energy from the sun that reaches earth and heats its surface is in the form of light. The warmed surface is not heated enough for light to produce a visible glow, but it does radiate infrared energy (heat) back toward space. To understand why, think of the familiar analogies red hot and white hot. Red, the longest wavelength part of visible light, comes from a cooler (less energetic) surface than white.
Certain greenhouse gases absorb some of this energy as it's being radiated back toward space, slowing its loss, with the net effect of keeping the surface warmer than it would be otherwise. Tyndall's measurements showed that water vapor is the most important greenhouse gas controlling surface temperature.
Water vapor? Isn't carbon dioxide the most important greenhouse gas?
Not at all, but that is a common misconception due to media hype and ill-informed politicians. Tyndall established this without a doubt, as have many other scientists, so it can stated with certainty. However, the relative importance of water vapor to the total greenhouse effect cannot be stated with the same degree of certainty. This is because the water vapor content of the atmosphere, the humidity in other words, is highly variable from day to day, place to place and constantly changing, ranging from virtually zero in a desert to as much as 4% in certain tropical climates. Physicists who have studied this agree with Tyndall that water vapor accounts for the lion's share of the earth's total greenhouse effect, probably on the order of 90%, but maybe even 95% as S.M. Freidenreich and V. Ramaswamy calculated in 1993.1 To put it another way, carbon dioxide plus all the minor greenhouse gases combined account for only a few percent of the planet's total greenhouse effect. This is true of the lower portion of the atmosphere, the troposphere where all weather originates and where we live. The relation is reversed in the thin air of the high stratosphere, but this is of very limited importance to the overall greenhouse effect because the temperature in this region is many tens of degrees below zero.
Most people are familiar with the practical importance of humidity as the paramount control of the greenhouse effect, although they might not be aware of it. Consider traveling to Florida during the summer, hot and sticky during the day and only a few degrees cooler at night. Imagine how different it would be hopping on a jet and flying to a desert city such as Las Vegas or Phoenix--as hot or hotter during the day, but rapidly dropping when the sun sets, and getting so cold that a jacket would feel good during the night.
What causes this difference?
Not carbon dioxide, which changes greatly from winter to summer, with less during the northern hemisphere summer because plants use it for growth. Carbon dioxide is pretty well mixed in the atmosphere just like oxygen so there's not much change from place to place. It's the difference in humidity, in other words, changes in the water vapor content of the atmosphere. Where it's higher, such as in Miami, there's a much greater greenhouse effect and temperatures don't fall at night nearly as much as they do in the desert where the air is very dry and the greenhouse effect is diminished.
Another way to look at this phenomenon is to consider how small changes in relative humidity impact the greenhouse effect. As an example, an increase in the relative humidity of only a couple of percent, say from 52% to 54%, hardly even noticeable, changes the greenhouse effect as much as doubling the present carbon dioxide content in the atmosphere.2
If this is true, why is carbon dioxide (and maybe methane) the only greenhouse gas the media discusses?
It's most likely not simple oversight, or the fact that water vapor varies so much from place to place. It might be because they don't really understand the greenhouse effect or because of the fact that there's no sensible way to blame humans for variations in humidity, although burning fossil fuels does emit a little water vapor.
Well, it really doesn't matter, does it? An enhanced greenhouse effect will heat the earth, eventually producing a disaster unless we take action to reverse the trend.
There are misconceptions here that should be cleared up regarding greenhouse gases before getting into more specific topics in later chapters, such as how carbon dioxide might be related to global temperatures and what might happen if it increases. It might seem trivial or even a matter of semantics, but the greenhouse effect is a concept important to understand because it is basic to climate change and the global warming theory.
The greenhouse effect, no matter what its cause might be or whether it's increasing, decreasing or static, is not the source of heat for the earth. Except for a modest contribution from the hot interior, the sun is the earth's only source of heat. All the greenhouse effect does is to slow the loss of the sun's energy back into space; it does not stop or prevent it. To use the example of Florida again, the temperature doesn't drop much at night during the summer, but it does drop. Energy from the heated surface is lost. What would happen if the sun didn't rise the following morning and on subsequent mornings? Heat loss would continue until the surface cooled far below freezing.
In this respect, the greenhouse effect acts something like insulation in a house. A furnace is capable of producing a certain amount of energy. Depending on the outside temperature, it can warm a house by a certain amount. The reason it cannot warm it beyond that amount is that the heat energy is constantly being lost through the windows, walls, floor, roof, not to mention the cracks and crevices, to the outside environment. If insulation is added, the heat loss is slowed and the furnace can heat the house more than it could before, but heat loss still occurs. It is not stopped completely.
This is an overly simple analogy that is nevertheless useful for understanding the greenhouse effect of the earth, as long as one is aware of the model's limitations. In fact, the earth's atmosphere does not actually work like insulation, a blanket, the glass in a greenhouse (or car) or any other physical barrier to heat flow. Greenhouse gases do not form a physical barrier preventing heat loss.
How does the atmosphere's greenhouse effect differ from these?
Greenhouse gases absorb some of the energy from the sun as it passes down through the atmosphere and more as it is reradiated at a longer wavelength back out into space. A constant exchange of energy occurs with the net effect that greenhouse gases slow heat loss to space due to radiation, but they do not form a physical barrier preventing convectional heat exchange, which is the main way heat exchange occurs in the atmosphere. The glass in a greenhouse does both.
This is important because convectional circulation is by far the most important mechanism for exchanging heat in the atmosphere. Hot air from the equatorial regions is carried toward the poles while cold arctic and Antarctic air moves in the opposite direction, giving rise to wind and weather. According to the calculations of atmospheric physicists, such convectional circulation causes the earth's temperature to be more than 100 degrees F cooler than it would be without convection, which is good unless a toasty 171 degree F day appeals. That's roughly what the earth's average temperature would be without convectional mixing of hot and cold air.3
Well, maybe greenhouse warming won't stop convection from operating, but it is still has the potential to cause dangerous warming. Isn't that correct?
Oh, the much maligned greenhouse effect--it never gets any credit. Everything from heat waves and floods to blizzards and drought gets laid at its doorstep. It should wise up and hire a good publicity agent.
To try to set the record straight--the fact that the atmosphere of the earth produces a greenhouse effect is NOT a bad thing. In fact, it's a very good thing. Without the greenhouse effect, there would be no life on the earth.
That's right. The greenhouse effect makes life possible on the earth. Of course, it's not the only factor contributing to the existence of life on this planet. There are many others, but it is one of them.
The reason is simple--temperature. Just as insulating a house helps make it warmer in the winter, the atmosphere's greenhouse effect slows heat loss from the surface and troposphere making the earth warmer than it would be otherwise.
How much warmer?
Estimates for the average temperature of an earth with an atmosphere and clouds but no greenhouse effect vary from a couple of degrees above zero F to a few degrees below zero, but all of them are far below freezing, even at the equator. There would be no liquid water and the earth would be a giant ball of ice, including the oceans, making life impossible.
It is interesting that the earth would be considerably warmer than this, just below freezing in fact, if it had no atmosphere at all. The reason is that clouds reflect a lot of the sun's incoming energy sending it back out into space before it can warm the surface. Clouds, of course, imply an atmosphere of some sort. The calculations from physics for determining earth's temperature without clouds or an atmosphere are shown at junkscience.com.4
Another way to look at this is that clouds increase the planet's albedo, the proportion of light striking the planet's surface that is reflected back into space. Measured albedo is always between 0 (a surface existing only in theory that reflects no light at all) to 1 (a theoretical perfect reflector). Other factors being equal, the higher the albedo, the brighter an object appears. The albedo of the earth is high, 0.37 compared to 0.13 for the moon and 0.15 for Mars, but Venus is considerably higher at 0.65 partially accounting for why the so-called evening star and morning star, depending on time of the year, is so much brighter in the sky than Mars.
Instead of either of these freezing scenarios, our planet's atmosphere has a lot of water vapor so we have a healthy greenhouse effect. As a result, the average temperature of the earth is well above freezing which is why we have so much liquid water. In fact, the surface is nearly three quarters ocean, with just over one quarter land. There were times in past geologic periods when water covered an even greater proportion of the surface and times when there was more land than today. We are currently somewhere between such extremes.
There is another important aspect of the greenhouse effect that never gets mentioned during media discussions of climate change and global warming. Perhaps it's of lesser importance because life might be possible without it, but if so, such life would face far greater challenges than is currently the case in terms of being able to quickly adapt to huge changes in temperature in a short period of time. This is precisely what would be required in order for living things to survive on a planet that lacked a greenhouse effect.
For an example of this, we only have to look at our nearest neighbor in space, the moon or Luna as it was known in Roman times. It's a world composed of rock that in some ways resembles the earth, but it's far smaller so its gravity is much less. In fact, its gravity is so low that it was unable to retain its atmosphere if it ever had one. Conveniently close to us is a world lacking a greenhouse effect that is the same distance from the sun as the earth, so each square meter receives the same amount of energy. What sort of temperature exists there? Close to the average of a degree or so below freezing mentioned earlier for the earth if it had no atmosphere?
That's not a bad estimate, but it only goes to show how misleading using “average” in reference to temperature can be. At morning, right before the sun begins to peep above the horizon, the surface temperature on the moon is far colder than anything remotely approached on the earth, hundreds of degrees F below zero, but the temp begins to rise as the sun climbs higher in the sky until the it's well above the 212 degrees F required to boil water on earth at sea level. The average daytime temperature is 225 degrees F while the night averages -243 degrees F, more than a hundred degrees colder than ever measured on earth. It is doubtful that any life from the earth could adapt to such extremes of heat and cold.
Of course the earth doesn't have temperature extremes like that, but there is a considerable variation between the poles and the equatorial regions. What is the average temperature on the earth?
That seems like such a simple question to answer, but as with so many questions dealing with climate, it turns out to be a surprisingly difficult problem. In fact, the best we can do is to make estimates that agree fairly well with each other.
First, there's the problem of defining what an answer to this question means. Is it enough to just take the average annual temperature for all weather stations and calculate a grand average? That would be biased to areas with people because that's where weather stations are located. What about all the wilderness areas, the oceans and Antarctica? How do we include those? And is one year's data enough? If not, how long a period do we need? And if climate is changing, as it always does, what are we really measuring?
These difficulties have been recognized since at least 1878,5 but have not stopped scientists from tackling the problem. Older sources typically gave a number on the order of 15 to 18 degrees C (57 - 64 degrees F), but modern sources place it closer to 14 degrees C, roughly 58 degrees F.
Even though a single number cannot be given with certainty in answer to this problem, the rather small range that has been determined makes it clear that our atmospheric greenhouse effect has led to a world much more suitable as a home to life than would otherwise exist. This basic fact is one that should not be overlooked in any discussion of climate and the greenhouse effect, but the media rarely mentions it. It is not unusual for the term “greenhouse effect” to be used interchangeably with climate change, but the two actually refer to completely different phenomenon. An “enhanced greenhouse effect” is closer to how global warming is often used, but even that term can be a bit slippery. A good piece of advice for anyone trying to understand the climate change controversy is to be precise in the use of terms and to be on guard for misused terminology, whether intentional or otherwise.
SUMMARY
Scientists have known since the nineteenth century that the earth's atmosphere produces a greenhouse effect, that is, certain gases absorb some of the longer wavelength radiation that travels back toward space from the sun-heated surface of the earth, thereby helping to retain some of the heat. Scientists of that time compared this to the way glass in a greenhouse traps heat from the sun. This is a limited analogy because greenhouse gases do not form a physical barrier preventing both radiation and convection like the glass in a greenhouse does. The effect of absorbing some of the radiation is to slow the loss of heat rather than preventing it, setting up an exchange of heat between the surface and the lower atmosphere.
Irish scientist John Tyndall in 1859 was the first to quantify the ability of various atmospheric gases to contribute to the greenhouse effect. He found that water vapor is far more important in this regard than all other greenhouse gases combined. Modern studies suggest that as much as 95% of the total greenhouse effect is due to water vapor in the atmosphere alone. An increase in the relative humidity of the air by less than two percent increases the greenhouse effect as much as doubling carbon dioxide from the current level.
Although global warming alarmists and the media often use the term “greenhouse effect” in a negative sense as a synonym for global warming, the two are not the same. The fact that the earth's atmosphere produces a greenhouse effect is one factor that allows life to exist on this planet. It keeps surface temperatures from dropping precipitously at night and from rapidly heating to intolerable levels during the day through the constant ongoing exchange of energy between the surface and the atmosphere. By slowing the loss of heat energy into space, moderate temperatures suitable for liquid water are maintained over most of the planet's surface.
If the atmosphere did not produce a greenhouse effect, all oceans, rivers and lakes would be solid ice with an average global temperature near zero degrees F or below and life as we know could never have developed. Instead, we live on a greenhouse-warmed world with a relative balmy surface temperature averaging somewhere in the neighborhood of 58 degrees F (14 degrees C).
NOTES AND SOURCES
(1) Journal of Geophysical Research, Vol. 98, p. 7255, 1993, S.M. Freidenreich and V. Ramaswamy, “Solar Radiation Adsorption by Carbon Dioxide, Overlap with Water, and a Parameterization for General Circulation Models.”
(2) Many sources point out the importance of water vapor in relation to carbon dioxide. One of the most accessible is here: http://www.junkscience.com/Greenhouse/
(3) Ibid
(4) Ibid
(5) Nature, Vol. 17, p. 202, 1878, D. Traill, “Average Annual Temperature at earth's Surface.”
CHAPTER TWO—CARBON DIOXIDE, GREENHOUSE GASES AND CLIMATE
Is it correct that the EPA considers carbon dioxide to be a dangerous pollutant and recommends that it be controlled and regulated just like any other atmospheric pollutant?
With the election of Barack Obama in 2008, this was no surprise. In March 2009, the EPA sent a finding to the White House stating that carbon dioxide and five other atmospheric gases are pollutants that endanger public health. Time Magazine announced this on their web site with the headline, EPA CALLS CO2 A DANGER--AT LAST.1 This is certainly an interesting development, particularly since the EPA admits that carbon dioxide is emitted by natural processes. It makes one wonder just what definition for the word “pollutant” they might be using, for if they are right, then each and every person on the earth is producing pollution with each exhaled breath. All other air breathing and carbon dioxide exhaling animals also fall into this category. We are all big-time polluters and are not about to stop.
Although that might be an interesting observation, it doesn't address whether too much carbon dioxide is dangerous and if it is correct to call it a pollutant.
Instead of slogging through a discussion of semantics that leads to no useful destination, a wiser course might be to consider some basic information about carbon dioxide in order to better understand how it relates to climate. A good place to start is the history of the atmosphere and the carbon cycle.
Contrary to media portrayals and popular belief, from a geologic standpoint, the amount of carbon dioxide currently in the earth's atmosphere is unusually low, not high. It is common knowledge among geologists that the atmosphere contained far more carbon dioxide for much of the geologic past.
Geoscientists who have studied past atmospheric composition think carbon dioxide was much higher in the earth's earliest atmosphere, perhaps as much as 10%. That's over 250 times more carbon dioxide than today's level. This early atmosphere was strongly reducing, quite unlike today's oxidizing or oxygen-rich atmosphere.2 In simplest terms, this means that if it were possible to climb into a time machine and travel back 3.8 billion years ago, the air would be breathable because it lacked oxygen.
No oxygen. Then where did it come from?
Oxygen started to build up in the atmosphere about 2 billion years ago as a waste product from the utilization of carbon dioxide in one of the most important chemical processes ever initiated on the earth, photosynthesis. Yes, photosynthesis, that hoary old favorite of eighth-grade science everyone had to memorize in grade school, is the reason the atmosphere of the earth has more than 20% free molecular oxygen making it unique among all known planets. Oxygen is a product of life and a telltale sign or signature. Free molecular oxygen in a planet's atmosphere is considered so unique that it is one of the things astronomers and exobiologists are looking for in their searches for other earths in distant solar systems.
Photosynthetic bacteria, dating back more than three billion years ago in the fossil record started the process of modifying the composition of the earth's atmosphere. As part of their life process, these bacteria used carbon dioxide and released oxygen as a waste product. The same is still true of modern trees and other green plants. It is a marvelously balanced system, perfectly symbiotic; plants use carbon dioxide from the atmosphere for their growth and release oxygen as a waste product. Animals use oxygen and exhale carbon dioxide. Plants depend on animals and animals depend on plants.
People who remember their basic science classes can skip this paragraph, but for the rest of us, a short review of photosynthesis is useful. The basic chemical reaction is the following:
CO2 + H2O ---> CH2O +O2
According to this reaction, given a suitable energy source such as light from the sun, carbon dioxide reacts with water to produce a basic sugar and free oxygen as a waste product. Notice that as part of the process, carbon is stripped from carbon dioxide and incorporated into the plant's tissue.
This reaction, one of the most important known, tells us the basic requirements necessary for plant growth. The three essential ingredients are: Sunlight, carbon dioxide and water. Eliminate any one of these and the plant dies. Everyone realizes that a plant will die if kept in the dark or not watered. Because carbon dioxide is an invisible and odorless gas, it is not commonly thought of as necessary for plant growth. Nevertheless, it is just as essential. Remove most of the carbon dioxide from the air and the plant will die.