'Global Warming And Climate Change'

The article on global warming is very interesting and informative; however, I am somewhat disappointed by the apparent bias against those who disagree with the popular view on global warming (C&EN, Dec. 21, 2009, page 11). The author did present opposing perspectives but showed disdain for minority dissenters that I believe is unhealthy in any scientific field.

Unfortunately, this attitude is common among those who support the most generally accepted theories or models in any field, whether it is the current global-warming topic or the "fact" that the world was flat in medieval times. Good science should always respectfully evaluate and consider the viewpoint of minority dissenters. Many significant advances start as unpopular dissent. Failure to respect the minority opinion has resulted in catastrophic failure in the past.

In addition, whether or not the current temperature trends are due to carbon dioxide emissions, I find the level of reliance on mathematical models of such a complex system for driving critical decisions disturbing. Although I am not intimate with climate models, I think it is fairly safe to say that the state of the art for current computational modeling of complex systems is not yet ready to drive critical decisions, whether they are in the field of climatology, economics, medicine, or any other.

James F. Pfanstiel Jr.
McMurray, Pa.

It was most refreshing to read Stephen K. Ritter's article. He did an excellent job reviewing in detail and without political comment both sides of the ongoing debate. I congratulate Rudy Baum as editor-in-chief for allowing this to be published.

Ritter clearly respected C&EN readers enough to present the facts and allow them to draw their own conclusions. Perhaps there is hope that after Baum's tenure, C&EN can return to its place as a respected technical nonpolitical journal.

Bob DeMarco
Louisville

"Global Warming and Climate Change" gives far too little weight to the facts from organizations such as the National Academy of Sciences (dels.nas.edu/climatechange/basics.shtml) and far too much to organizations such as the Nongovernmental International Panel on Climate Change, the same folks who would have you believe that cigarettes don't cause lung cancer (www.heartland.org/suites/tobacco).

Russell R. Dickerson
College Park, Md.

Ritter's cover story was quite informative, presenting a wealth of facts in a well-written, balanced article. However, the sequence of photos on page 11 is confusing. The caption reads: "Satellite images show the sudden collapse of the Larsen B Ice Shelf, in Antarctica, from Jan. 31 to March 7, 2002 (from left). A total of 3,250 km² of the shelf collapsed." The sequence shows a wide-open expanse of water on the left, with a thoroughly frozen-over bay on the right. Either the photos are out of sequence or here we have evidence speaking strongly against global warming! (See Editor's Note below.)

Bruce Phelps
Clayton, Calif.

I would like to thank the editors of C&EN for Ritter's wonderful article. It was a well-written and thought-out presentation of the issues being debated about the role of modern industry on Earth's climate. It is a "weight-of-evidence" piece comparing the evidence in favor of or against the theory of the anthropogenic origin of global warming.

What surprises me is that the author did not discuss the historical angle: More than 100 years ago, scientists argued that the release of "carbonic acid" by the burning of coal could actually increase Earth's average temperature.

None other than Svante Arrhenius argued in 1896 ("On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground," Philosophical Magazine 41: 237-76) that periods of glaciation and subsequent warming were largely due to changes in the concentration of carbon dioxide based on the "hot house theory" that the atmosphere is transparent to visible light but opaque to infrared, which was begun by Fourier, Pouillet, and Tyndall. Arrhenius stated: "If the quantity of carbonic acid increases in geometric progression, the augmentation of the temperature will increase nearly in arithmetic progression." In 1906, he hypothesized that "the enormous combustion of coal by our industrial establishments suffices to increase the percentage of carbon dioxide in the air to a perceptible degree" and that this would result in "more equable and better climates" ("Worlds in the Making").

Arrhenius saw that the conversion of subterranean coal into atmospheric CO₂ would increase global temperatures, which he saw as a positive development for humankind as it would preclude the return of another ice age. Moreover, in his article, Ritter cites that IPCC currently estimates the climatic sensitivity (the amount of average global temperature change by doubling the concentration of CO₂) of 2.0–4.5 °C, very close to Arrhenius' estimate of 5-6 °C. What is truly amazing is that Arrhenius was able to make these estimates and predictions when he did. He understood that Earth is warmed by ultraviolet and visible light but radiates IR radiation.

Today, we would use Planck's law to calculate the intensity of the IR radiation given off by Earth and use laboratory measurements to calculate how much of that IR radiation would be absorbed by the CO₂ in the atmosphere. However, in 1896, Planck had yet to publish his law and Anders Jonas ÅngstrÖm had not yet published the first laboratory measurements of the absorption spectrum of CO₂. Arrhenius had to use the Boltzmann-Stefan law to approximate the amount of energy given off by the sun-warmed Earth. Furthermore, the only way he could estimate the ability of CO₂ in Earth's atmosphere to absorb this energy was from Samuel Pierpont Langley's work with light reflected from the moon to Earth.

Given the poor tools available to Arrhenius, his work and prediction in regard to global warming are astounding. All of this he hypothesized long before there was any evidence for actual increases in atmospheric CO₂ concentrations or global temperatures. This indeed is a powerful bit of evidence in favor of the anthropogenic hypothesis for global warming that might have added an interesting element to Ritter's article.

David E. Kimbrough
Santa Clarita, Calif.

Now that it has been shown that the "respectable" scientists who have been leading the "global warming" charade have been purposely hiding data, "fudging" other data, and defining any research that shows the cooling trend of the past decade as "not peer reviewed," perhaps it might behoove the leaders of ACS to rethink the "official policy" supporting the contention that there is an anthropogenic "crisis" looming due to CO₂ emissions.

Hopefully, there is enough time to make the truth widespread before the U.S. gets caught up in the cap-and-trade fiasco. Now there is a crisis waiting to happen!

George St. George
Pearland, Texas

Thank you for publishing Ritter's article on climate. It was a pleasure to read something about that issue that is scientifically articulate and devoid of political bombast.

I worry about reliance on the IPCC modeling because we have blundered before when trying to predict long-term trends by extrapolating present-day data.

Paul Ehrlich, an eminent thinker, predicted in his 1968 book "The Population Bomb" that the world would be devastated by overpopulation long before now, and yet European countries today do not produce enough children for their societies to function without relying on foreigners.

In 2007, many were predicting that cruise ships would soon be traveling an ice-free Northwest Passage, yet the passage was about as frozen this past summer as it was when Roald Amundsen sailed those waters early in the 20th century.

We should all continue to work toward lowering carbon dioxide emissions—as we did the sulfur gases of the acid rain era—but we must refrain from making predictions for the distant future of a world that we still understand only incompletely. The global-warming alarmists make science and scientists look less than disciplined.

Paul A. Barra
Reidville, S.C.

I got to the part of the global-warming article and noticed the Nongovernmental International Panel on Climate Change (NIPCC) mentioned. For completeness, you should have included some background on NIPCC, which can be found here: rawstory.com/2009/12/climate-skeptic-group-nipcc-extensive-ties-exxonmobil.

Do corporations lie for money? Corporations do. And if Rudy Baum upsets so many people, he is clearly doing something right.

Mark Morey
Goleta, Calif.

Thanks. The article reads well. What a good summary. People really are confused about this issue, and this type of press helps us all.

David C. Brewster
Raleigh, N.C.

I would like to draw attention to one key assumption of the cover story on global warming: the existence of actual scientific debate on the issue. This is a tremendously important question, because any action policymakers take to address anthropogenic global warming (AGW) rests in part on whether the public perceives that scientists are still debating the question.

On some level, scientists always debate—debate is critical to the scientific method. However, to the public, the word "debate" means that the core question is still up in the air. As stated in the cover story, IPCC is a collaboration of 2,500 climatologists; NIPCC, representing the opposing viewpoint, has 35 members. Most of the information cited in the article from NIPCC sources was not peer reviewed.

Furthermore, what was omitted from Ritter's article is that the Heartland Institute, which publishes NIPCC's reports, has received more than $800,000 in contributions from ExxonMobil. Incidentally, they also received significant funds from Phillip Morris and spoke out on the side of the cigarette companies in the secondhand-smoke debate.

In effect, the article considers the opinion of a small group of scientists funded by special interests as somehow carrying equal weight with the opinion of the vast majority of researchers. Is this really a serious debate that could result in the overthrow of the AGW theory?

Whether there is actual debate about AGW might seem academic, but the oil companies (especially ExxonMobil, which leads the industry in spending on lobbying efforts) have spent significant money and energy on convincing the public that there is a debate on climate change. As recent polls have shown, their strategy might be working, to the chagrin of those genuinely concerned about the future of our planet.

Constantine Y. Khripin
Albuquerque, N.M.

I wish to commend Ritter for the excellent article on global warming. One particular paragraph struck me as crucial in the debate on the validity of the Intergovernmental Panel on Climate Change's predictions that catastrophe is imminent. I refer to the certainty that IPCC claims for its conclusions, which is a 90% confidence level.

I have studied statistics and have used them my work. I have read countless scientific papers that rely on statistical confidence levels. The universal rule is that there must be a minimum 95% confidence level to support a valid conclusion; 90% will not do. The difference between 95% and 90% confidence is one standard deviation, and that is a big difference.

Yet IPCC demands that hundreds of billions of dollars be spent on a statistically weak foundation. When global-warming data merit a 95% or higher confidence level, I will be more enthusiastic in supporting IPCC's goals.

Norman Fine
Sewell, N.J.

Thank you for "Global Warming and Climate Change." It provided an excellent and broad perspective on the climate-change debate. Public opinion is often held hostage by advocacy journalism. It is rare to find an article that describes the scientific arguments as clearly and completely, allowing the reader to form an opinion based on fact rather than emotion.

Marcia Torobin
Santa Fe, N.M.

Thanks for the cover article on global warming. It provided a balanced evaluation of both sides of the global-warming debate.

I think others would agree that an important part of discussing a question like this includes reviewing the underpinnings (data and facts) the opposing sides are using to reach their conclusions. The article provided an ample amount of that kind of information in a summarized manner.

As chemists (if I might presume to speak for part of your audience), we appreciate details like the values for CO₂ and the range of the error. We would not be afraid of terms like standard deviation. By contrast, facts and data are generally not used in the arena of political debate where defense of a topic is done more effectively through generalization and hyperbole.

As an observation, not a criticism, I find it curious that no mention is made of the possible contribution of man-made refrigerants to global warming. Is it likely they are not a contributing factor because they are not mentioned? Perhaps there is no substantive link between CO₂ and man-made refrigerants, even though both are components, which, even at low concentrations, are implicated in significant changes in the atmosphere.

Keith Hammond
Corpus Christi, Texas

As editor-in-chief of C&EN, Rudy Baum is a journalist with a pulpit; however, as a scientist, he is biased and needs to be more objective before he completely loses his credibility with ACS members. Historian Joseph Needham's observation is apt: "Belief can alter observations; those with a particular belief will often see things as reinforcing their belief, even if they do not."

The sun is an integral part of Earth's climate system. It has been established that orbital variations, including eccentricity, axial tilt, and precession comprise the three dominant cycles that make up the variations in Earth's orbit.

In addition, solar sunspot activity also corresponds to climatic changes. The combined effect of the variations in these cycles creates changes in the reception of solar radiation on Earth's surface. It has been established that slight differences in the amount of solar energy reaching Earth have a powerful effect on the planet's climate.

The most significant climate processes of the past several million years are the glacial and interglacial cycles. At present, Earth is in an interglacial period that has lasted for about the past 10,000 years. It has also been established that the average temperature on Earth for the past 100 million years was much warmer that it is today.

The real question is what is the impact of global warming upon humanity? Is this risk greater than humanity's exponential population growth?

Robert Fuhrer
San Juan, P.R.

I wish to thank Rudy Baum for assigning Ritter the task of reporting "Global Warming and Climate Change" without prejudice. Congratulations to Steve Ritter for providing ACS membership with an excellent and unbiased discussion on this important topic. This cover story provided factual data and opinions from both sides of the debate on human impacts of warming and climate fluctuations.

In my world travels, I have been able to view both sides of the debate. National parks in the U.S., Canada, and Argentina allow visitors to tread on glaciers that are both receding and expanding. These observations and the debate discussed in the cover story convince me that our climate does change, but in my own mind I cannot yet decide if changes and warming are the result of anthropogenic CO₂/human activity and if the human race can make significant changes to curtail warming and climate variations. Does anyone else feel the same as I do?

What causes me more consternation is the writers of letters to the editor who suggest that they know the mind-set of chemists. In his letter to the editor in the same issue (page 4) Klaus Schaper berates Jihong Cole-Dai for stating that "many chemists are skeptical about the science of global warming," followed by his own contention that "most chemists believe in man-made global warming." "Many" and "most" are neither defined nor referenced.

As a 35-year member of ACS, I have yet to be asked my opinion on the subjects. I have not seen an opinion poll that would allow one to aver either way in the debate. Schaper justifies his "most" statement with a quasi-tutorial and diatribe of "basic physical chemistry" principles. Before either of these and other letter writers continue to infer that I or the collective group of chemists are in one camp or another, I recommend that polling data be provided to justify such statements. I am certain that my distant cousins in Princeton, N.J., would be more than happy to conduct such an opinion poll of ACS members/chemists to determine how "many" and what "most" (say perhaps more than 50%?) chemists have decided about anthropogenic global warming, climate change, CO₂ effects, clean air, and other environmental questions.

Darrell L. Gallup
Houston

The agreement by several world leaders on Nov. 14, 2009, that no climate-change agreement could be reached at Copenhagen is in accordance with the record to date of failures to address this future global catastrophe.

At the Rio Earth Summit in 1992, world leaders, including President George H. W. Bush, pledged to take actions that would avoid dangerous buildup of greenhouse gases. But in 1997, President Clinton recognized that there was no chance the Senate would ratify the Kyoto protocol, so he did not even attempt it. Without participation by the U.S., Australia, China, and India, moderate emission reductions achieved since then by European nations under their Kyoto targets have been overridden by increases in the nonsignatory nations. As a result, global greenhouse gas emissions are about 25% higher than the base 1990 level. In 2007, no agreement was reached at the Bali, Indonesia, conference. Now we have dim prospects for any international agreement to replace Kyoto, which expires in 2012.

Perhaps the wisest course is not to depend on getting any international agreement but to view this as a moral challenge to each and every nation to take the most effective actions that it can under its individual situation. The biggest reduction targets would be adopted by the rich nations that have been responsible for most of the atmospheric pollution now present and that have the wealth and technologies to best reduce their emissions. By setting an example of progress in making drastic reductions and by furnishing financial and technical aid to nations such as China and India, the rich nations would have worldwide influence for actions by all.

Scientists have given us a picture of the danger to future generations of a business-as-usual economy, but unfortunately our future is entrusted to politicians, and the vision of too many of them is limited to the next election.

Will we reach the tipping point before taking action?

John Burton
Washington, N.J.

There is legitimate reason to thoroughly investigate the allegations of data manipulation at the University of East Anglia. The credibility of the sciences is at stake.

Beyond that, other objections can be legitimately lodged against your statements (C&EN, Dec. 14, 2009, page 3). For example, the rise in ocean levels should be considered in context of historical rises in ocean levels that go back thousands of years. In fact, sea-level changes have moderated over the past century.

Perhaps, however, the deeper question is civilization's proper and logical response to climate change. To say that the climate changes is no different from saying that the sun rises in the east or that hydrogen and oxygen combine to make water.

Change is a part of life—always has been, always will be. Our success as a species has not been, in contrast to many other life forms, based on any ability to create a static climate. It has been based on several important God-given advantages including the following:

• Our ability to communicate and cooperate with fellow beings; we do so at a very high level.
• Our ability to study the world around us, identify available resources, and use those resources for our benefit.
• Most important, our ability to adapt to change. We inhabit forests, swamps, glaciers, mountains, plains, and deserts. We deal with summer and winter, drought and monsoon.

To assume that we cannot use change to our advantage is insulting to our species and a method of declaring defeat and self-destruction. I reject this concept and urge other students of science to do the same.

Michael Kerner
Lisle, Ill.

The three main points that I take from the so-called Climategate are as follows: First, none of the e-mails cast any real doubt on the validity and soundness of the science behind and in support of the hypothesis of anthropogenic global warming (AGW). Second, the e-mails do bring into question the motives and scientific integrity of some of the people involved. Third and finally, the e-mails will actually foster and improve the ability of those respected and credible scientists with alternatives to a purely AGW hypothesis to better publish, defend, and improve their hypotheses concerning climate change.

With respect to these points, in my opinion, Baum's editorial was extremely disappointing, highly political, and ultimately inconsequential. I expect better from the editor of C&EN, but I am learning not to.

Matthew D. Wessel
Sisters, Ore.

As I have suggested to C&EN many times, do not waste time and energy on the pursuit of CO₂ reduction. Go after real pollution, such as the toxic metals discharged from coal-fueled electrical power plants. Or consider California EPA's recommendation that solvents such as parachlorobenzotrifluoride and 1,1,1-trichlorethane be used as solvent carriers for the application of two-component paints. This list of more than 20 halogenated solvents does not include any "good" solvents for polyurethanes. But what concerns me is the trivial use of these halogenated solvents (one-time use) before they are introduced into the environment.

A. Frank Leo
Palatine, Ill.

I was disappointed to read Baum's excuse-making for the fraudulent science promoted by the University of East Anglia's Climate Research Unit (C&EN, Dec. 14, 2009, page 3). The editor tried to pass off the fraud as merely "trying to correlate disparate sets collected by a number of different methods." This, however, does not explain why Phil Jones in his e-mail stated that he performed this "trick" to "hide the decline." In other correspondence, the writers express their disappointment of the results and can't explain the lack of warming in recent years.

True science should not allow an agenda to hope for or even expect certain results but rather let the facts speak for themselves. Has the editor even considered the possibility that periods of global warming and global cooling are the result of external factors (solar fluctuations for example) other than man-made? Or is this type of thinking considered scientific heresy, much like at one time considering the possibility that Earth is round?

C&EN should reject any fraud that takes place in the scientific realm because such fraud, if allowed to persist, presents a credibility problem for all science.

Mark P. Wagher
Aiken, S.C.

Among the various and sundry graphic presentations of atmospheric carbon dioxide concentrations versus suspected sources, I have yet to see one contrasting world population increases over time versus atmospheric carbon dioxide concentration increases over the same time period. Is C&EN aware of such a comparison, and if so, where may I see it? All mammals exhale carbon dioxide, but Homo sapiens is the only species that has undergone a huge historical population increase.

Richard D. Stacy
Montrose, Colo.

As a regular reader of C&EN, I would like to see a few articles on climate change that represent dissenting views.

As an engineer with past experience in data analysis and modeling, I have read a large number of papers and reports on climate change with a special interest in the area of analysis and modeling. Most knowledgeable persons would agree that Earth is in a long-term interglacial warming trend, even though IPCC members have reluctantly agreed that global temperatures have remained statistically essentially flat over the past six to 10 years.

Regrettably, in an outsider's view, the debate on key climate-change-model issues has been very limited. Since the first IPCC assessment reports were published, the main debates appear to have focused on the magnitude and rapidity of onset of the catastrophe before us.

The key issue is the magnitude and rate of change predicted by the various models. Based on my readings, it appears that a wide disparity exists in how these models could handle the interaction of greenhouse gases in the atmosphere with water—water in the form of humidity and/or clouds, including their altitude, type, density, area coverage, and whether it is day or night.

How a model handles interactions can lead to an extremely wide range of results. IPCC-recognized (approved) models seem to consistently treat water in the atmosphere, regardless of form, as a significant multiplier of the effects of other greenhouse gases (CO₂), leading to higher temperatures. Furthermore, details of IPCC models do not appear to be available outside of its government-funded research-supporting organizations.

It would be a service to the technical community if one or more articles in a future issue of C&EN explored or opened debate in this soft area of climate-change technology.

Tim McNamara
Chesterfield, Mo.

For the most part, I think Stephen Ritter did a pretty good job of presenting the pros and cons of anthropogenic warming. However, toward the end of the article he reveals his true colors.

On page 21, he starts a paragraph, "Despite the evidence laid out by IPCC and mainstream climate scientists." The obvious implication is that everyone else must not be "mainstream." I wonder if all of the skeptics he quotes would consider themselves to be "non-mainstream"?

John Hofmann
Watchung, N.J.

It is time to face the facts regarding alternative energy. The scientifically unfounded belief that man-made carbon dioxide is a significant threat to the environment has created an unwarranted emphasis on the development of alternative sources of energy such as wind, solar, geothermal, and biomass. A recent report of the National Research Council adds perspective to the situation. These combined sources contribute less than 2.5% of U.S. electricity.

Under a business-as-usual scenario, they will supply only 8% of U.S. needs by 2030. To achieve a 10% share by 2020 and 20% by 2030, policies must be in place to "encourage the development of advanced technologies, more financial investments, and greater deployment of renewable sources of electricity." To reach the 20% level, wind power would require the investment of $100 billion and construction of 100,000 wind turbines. A current project in Texas to construct a 600-MW wind farm, funded with stimulus money and tax breaks, will be built with wind turbines made in China!

Alternative energy industries, already recipients of huge government grants and subsidies, are now whining that failure to pass cap-and-trade legislation is hindering their development efforts. EPA stands ready to subvert the legislative process and declare that man-made CO₂ is a threat to human health and welfare. Climate alarmists are attempting to sabotage the coal industry and destroy the source of 80% of the U.S.'s electrical power.

Focusing on alternative energy sources rather than on our current great wealth of carbon-based natural resources is destructive to our nation's welfare. We have more coal, natural gas, and untapped oil reserves than most of the developed world. Funding of more oil exploration, construction of more coal-gasification plants, and the development of a natural-gas distribution system may prove to be our salvation.

Realistically, the U.S. must operate on a carbon-based energy system for the foreseeable future, unless nuclear power receives the commitment it deserves.

There is no "consensus" on the potential threat of man-made CO₂. Many thousands of highly qualified climatologists and other scientists repudiate the conclusions of IPCC and other politically motivated groups.

Albert Z. Conner
Wilmington, Del.

Before reading the recent article on climate change, I was convinced that Earth was getting warmer but skeptical that we were entirely the cause. After seeing the amount of glacial retreat in Alaska and Antarctica and the thinning of Arctic sea ice, how could one not be convinced of global warming? It does not make sense, though, that a system as complex as Earth would be completely dependent on a single variable like carbon dioxide to regulate its temperature.

After reading the article and looking on my own into how ICPP determines "average global temperature," however, I'm now skeptical on both counts. I was not aware of the Pacific decadal oscillation and the previous opening of the Northwest Passage in 1940. What other cycles of our planet are we are unaware of or do we overlook?

I believe it is short-sighted to use a single variable to explain any complex system. Correlations can be dangerous if you don't take them with a grain of salt. Most of the medical alerts put out by the media are based on ridiculous relationships. Here's one I can make up, for example: If you line up the carbon dioxide curve since 1800 with a similar plot of menarche in women, they also line up very well. Does this mean that atmospheric carbon dioxide causes girls to reach puberty at an earlier age? Of course not, because there are many controlling factors in human development. How then, can we do the same for Earth?

Pollution is bad, and we should not treat the planet like a bottomless sewer. Carbon dioxide may be one piece to a very complex climate puzzle, but to relate the temperature and overall climate of Earth to a single variable is a bit overzealous.

Jim Michels
Naperville, Ill.

The June 2009 issue of the "BP Statistical Review of World Energy" provides the following figure for worldwide primary energy consumption for 2008: 11,294.9 million tonnes of oil equivalent (toe). Converting toe per year to electrical units gives 17.14 terawatts (TW). Earth's solar influx is 1.7439 x 10¹⁷ W, so we were using just under one part in 10,000 of the solar influx.

This is not the full story, because the report considers only the following sources of primary energy: oil, natural gas, coal, nuclear energy, and hydroelectricity. It does not include photosynthesis, which is the primary energy source for a great many of our essential products, including food for both people and domestic animals; wood for fuel, which is still used to a large extent for household heating in many areas; wood for construction and for furniture; wood for pulp and paper; natural fibers; compounds such as latex and triglycerides that are derived from plants and used as chemical feedstocks; and plant-derived drugs, legal and otherwise, including alcohol and nicotine.

Regarding food, the average person requires about 2,200 kcal/day, a rate of about 100 W. For the current population of more than 6 billion, that comes to 600 GW or 0.6 TW. Photosynthesis of food is not a particularly efficient process, because only parts of the plants used for food are edible. I have no data for this, but the solar energy needed to produce the world's food supply must be much, much greater than 0.6 TW. The effect is multiplied even further if plant material is used to feed animals that are in turn used as meat.

The BP report starts with 1998, so we can see what has been the recent trend in energy use. The primary energy consumption in 1998 was 8,888.5 toe. The ratio of 2008/1998 comes out to be 1.27, so a 27% increase for the decade. If this trend continues, it would result in a doubling in slightly less than 30 years or a factor-of-10 increase in less than 100 years. At that rate, the energy requirement by 2408 would equal the entire solar influx.

Obviously, this is an absurd outcome, but the point I am trying to make is that continuous exponential growth is impossible. However, the devotion of human society to growth is so engrained that we completely ignore the obvious limitations and continue on as if there were no problem. In regard to the current concern about global warming, in a sense it is a red herring in that it diverts attention from the fact the basic problem is this insane concept that growth is marvelous and inevitable. The combination of population increase and a simultaneous increase in the use of energy per capita have put the species on the fast track to disaster.

At the age of 85 and with only one descendent, I don't really have any direct vested interest in the future, but I find it sad to face the fact that the human species seems determined to destroy this marvelous biosphere of which it is a part.

Robert E. Spenger
Big Pine, Calif.

In response to "Global Warming and Climate Change," I ask: When will we get it understood? If you heat Earth, CO₂ will be released from oceans and rain droplets (as they warm) exactly as we see it now. This is precisely predicted by Henry's law on the solubility of carbon dioxide, which I calculate is 59 ppm CO₂ average released for every 1 ºC global temperature rise. Am I the only one in the world to observe and report this? CO₂ in the atmosphere is a direct response to the heat sinks in which it is dissolves—or in the current case, does not dissolve.

The world has warmed, and increased CO₂ is the direct response.

John J. Griffin
Houston