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Mr. HASTERT. Using Illinois CO2 emission growth as compared to that of an industrial province in China, this shows graphically how CO2 emissions abroad are increasing at a greater rate than domestic emissions. The implications are clear. Onerous new taxes designed to further reduce emissions would be shortsighted because though these questions have international implications, the United States alone will bear the cost for any actions we might take.

Those decisions have real consequences for real people: truckers who will pay higher prices at the gas pump; low income families who already struggle to pay the monthly electric bill; farmers who rely on affordable fuel to feed the world; and all who buy consumer products that are shipped.

Mr. Chairman, I appreciate the opportunity to be here today. I certainly look forward to the testimony before us.

And I would like to ask that Mr. Franks' opening comments be put in the record.

Mr. SHARP. Without objection, it will be.

Let me ask my colleague from Texas if he has any opening remarks. Mr. Washington.

Mr. WASHINGTON. No, Mr. Chairman. I have studied the material. I may have a statement to make at the close of the hearing, but I would like to reserve that right, if I may.

Mr. SHARP. Certainly.

Mr. WASHINGTON. And I would like to hear from the panel of experts. I commend you on getting us all together for this very important hearing. I have heard from several constituent groups down in my area that are very much concerned about this issue.

I think it is an important topic for our consideration and appropriate that you are holding the hearing. I thank you, and I am happy to be here to hear from the experts.

Mr. SHARP. Appreciate that.

[The prepared statements of Messrs. Franks and Stearns were received for the record.]


Mr. Chairman, I want to join in congratulating you for holding today's hearing on the issue of Global Warming. I look forward to learning more about this important issue from today's witnesses.

I believe the fundamental issues that pertain to Global Warming are how much warming will occur if we do not change our current practices and how soon will these changes will occur. It is my belief, that there is a general agreement amongst scientists that our global climate has warmed. However, there does not appear to be consensus on the cause of this warming.

I believe it is important that any congressional action on this issue should be done on the basis of empirical scientific data and not emotion. The national academy of sciences has recommended actions that seem to be in line with this philosophy. The NAS recommendations are cost-effective and call for increased research while postponing radical action until better information is available.

I understand that the U.S. National Action Plan embraces this same concept which was included in the Energy Policy Act considered by this committee last year. The Energy Act permits corporations to undertake voluntary measures to reduce emissions and carbon fixation. I believe that until better scientific data is available, that this approach provides greater flexibility for the business community which is crucial for U.S. firms to compete internationally.


Thank you, Mr. Chairman. It's a great pleasure to be here today as a new member of the Energy and Power Subcommittee for this important hearing on global climate change.

I believe that it's important that we closely examine the possibility of global climate change and base our political decisions on hard scientific evidence.

As we know, environmental policies effects every segment of our society and economy. We need to address those serious and immediate environmental challenges and, at the same time, lay the foundation for understanding of long-term issues.

As someone who has come to Congress with a background in small business, I will be especially eager to hear how proposals to limit so-called greenhouse gases will effect our economy and competitiveness.

I congratulate Chairman Sharpe for holding these hearings today, and throughout this Congress, look forward to a full examination of the possibility of global climate change, hearing experts of all points of view on this important issue.


Mr. ALBRITTON. Thank you, Mr. Chairman. I am Dan Albritton. I direct NOAA's Aeronomy laboratory in Boulder, Colo. A special focus of our scientists has been on ozone-depletion and greenhouse gases. I have also been personally involved in providing scientific advice to U.S. policymakers as well as those in the U.N. on those two issues. Therefore, I certainly value the chance to return to your subcommittee and summarize the current scientific understanding of the issue of global warming.

The question that literally brings us here today is, What will the Earth's climate system do in the 21st century? A quick answer is it will vary. This answer is perfectly correct but it is deceptively glib in that it masks two very, very important points. The first point is that it is very clear that the Earth is fundamentally a planet of change.

We have all seen the recent tragedy of the Sahelian drought in Africa. Earlier this century, the Midwestern Dust Bowl in our country was another example of a high-impact, short-term climate variation. Even earlier historical records document the little Ice Age in Europe in the 15th and 16th centuries in which large-scale habitation and agriculture patterns disappeared or vanished-or moved.

These climate extremes were clearly a product of an inherently variable climate system. Such natural climate variations have occurred in the past, as I have indicated. They no doubt will be a part of our climate in the future.

The second point, though, about our planet being a planet of change is one that has arisen only in the last 100 to 150 years, and that is that we humans now have the industrial capacity, the chemical capacity to cause climate change ourselves by our own actions on scales possibly dwarfing those that I have given reference to. It is this potential that we can interfere with the climate system that, of course, motivates this hearing today.

It also raises associated policy questions. What could happen as a result of our activities? What could be done about it? And, in your camp, what should be done about it?

With the Climate Convention having been signed in Rio last summer, these type of questions and the follow-on decisions certainly lie ahead for both United States and for international decisionmakers. I applaud the calling of this hearing as a part of the process of information gathering to make meaningful and cogent decisions associated with these questions.

As it was for the environmental issue of ozone depletion, confidence in the science of the phenomenon will undoubtedly be a big factor in the debates that all of us will be engaged in during the next couple of years. I am very pleased to be asked to summarize what we do know and what we don't know about this issue of global warming. And let me make five points, ranging from what we are absolutely sure of to what we don't know.

First of all, a certainty. The greenhouse effect is real and it is a natural part of our planet. If our atmosphere did not contain the greenhouse gases of water vapor, carbon dioxide and ozone the temperature of our planet would be much, much colder. In fact, it would be ice-covered. As it is, these gases in our atmosphere trap part of the outgoing heat that would otherwise be radiated to space, retain it within the atmosphere, and yield the comfortable planet that we know.

Why then is the greenhouse effect so often labeled as an environmental problem? The answer is that we have begun to change this natural part of the planet, and that gets me to my second point.

The second point is what I would call a highly confident observation, and that is, that it is abundantly clear that human activities are increasing the abundance of many greenhouse gases. Carbon dioxide abundances have definitely increased by 25 percent in the industrial era, and methane, another greenhouse gas, has doubled in its abundance.

Because of their long residence times in the atmosphere, many of these gases will persist for decades, even centuries, after they are emitted, and therefore whatever they are doing to the planet there is an element of irreversibility here in the aspect of global warming.

The third point I would call a prediction with our best tools, and it is the following: Current climate models and most climate scientists predict that if the growth of greenhouse gases continue, the likely response of the planet is a global warming. For example, the models predict that the eventual warming arising from the time that CO2 will double, which will occur sometime in the next century, that could be in the range of 3 to 8 degrees Fahrenheit. If, indeed, such a warming were to occur in the future, it would be larger than any of the natural variation we have seen in the last 10,000 to 15,000 years.

The fourth point I will call a judgment call, and it relates to the question, Have you scientists seen any evidence that greenhouse warming has actually already occurred? The large majority of climate scientists believe the jury is still out on that question. That is, the predicted 1 to 2 degrees Fahrenheit warming that should be occurring right now as a result of the gases we have already put

in the atmosphere is simply too close to the natural variation, the poorly understood natural variation, to make a call as to whether the warming trend of the last 100 years is all natural or partly greenhouse, or whether there are natural processes offsetting what could even be a larger greenhouse warming. It is too close to call at the moment.

The fifth point I wanted to make, and this would be an unknown, is what science cannot do at the moment. Current greenhouse models are not smart enough. They don't have the capability to predict what the greenhouse effect will do for a particular region, say, of the United States, or for a particular year. While the large-scale predictions of these models are deemed very robust, such as warming over continents, dryness over continents, the current models are not yet good enough representations of the small-scale processes to say whether the United States drought in 1988 was, in part, or not at all, due to the greenhouse effect. However, scientists are saying that such droughts, such extreme events, are likely to become more frequent under a period of global warming.

The views that I have summarized on these knowns and unknowns are based on the recent international scientific assessment of the understanding of global warming that has been done by the world scientific community under the auspices of the United Nations. I draw your attention to the fact that another updating of this scientific understanding is planned for next year, hopefully to be timely if the Nations convene under the Climate Convention and debate what future courses might be appropriate.

Well, will there be surprises in the science in the future? Yes, certainly. But I would prefer to call these surprises "discoveries". Let me illustrate to you two recent discoveries to show how science is unfolding on understanding the greenhouse effect.

First of all, we have learned just within the last year that the chlorofluoro carbons [CFC's], which we have decided to eliminate because of their ozone depletion, are not as potent greenhouse gases as we originally thought. This means that the predictions of global warming in the future have decreased a little with that knowledge.

The second point is that we have learned that pollution. aerosols-these are the particles that come from our industrial emissions-shield some of the sunlight from reaching the surface and, in fact, introduce a cooling effect.

The importance of aerosols to global warming is that this was a term not in previous climate models and it is now being assimilated. The importance to policy is the following: We are pledged under the Clean Air Act to reduce industrial emissions of SO2, and therefore reduce aerosol particles in the future, which would eliminate that offsetting cooling and potentially then show a much larger greenhouse signal.

So here is a bit of good news that CFC's are not as potent in the greenhouse as we thought; and, second, that we might have a temporary mask, one that could disappear on greenhouse warming. I should note that both of these discoveries refine the picture of global warming rather than drastically alter it. Indeed, the principles underpinning the greenhouse effect have stood up under scientific inquiry for the last 22 decades.

Research efforts like the U.S. Global Change Program are continuing to refine understanding of the greenhouse effect. Such answers, though, don't come easily, and they don't come quickly. Nevertheless, the fundamental understanding of the natural processes that relate to the well-being of mankind are always cost effective. Consider, for example, the cost of a single Salk-Sabin vaccine for polio in comparison to the economic cost and the human cost of life in an iron lung. Regarding our health and the health of our environment, it is the price of ignorance that we can't afford.

Thank you very much for the invitation.

Mr. SHARP. Thank you very much, Dr. Albritton.

[The prepared statement of Mr. Albritton follows:]


Mr. Chairman and members of the subcommittee: My name is Dan Albritton. I am Director of the Aeronomy Laboratory of the National Oceanic and Atmospheric Administration (NOAA). Our Laboratory, located in Boulder, Colorado, studies the global chemistry and dynamics of the Earth's atmosphere. Our scientists and their colleagues have contributed greatly to recent advances in understanding stratospheric ozone depletion and greenhouse gases. I have also been involved in providing scientific advice to United States and international policymakers on the ozone layer and the greenhouse effect. Therefore, I appreciate the invitation to return to your subcommittee to describe the current scientific understanding of global warming and its relation to the policy decisions that lie ahead.

As you requested, I will focus this summary on 3 major areas: (1) the current status of our scientific understanding of global warming, including recent research advances, with an emphasis on the policy-relevant aspects of the science; (2) the plans of the international scientific community to provide an updated. assessment of the state of scientific knowledge; and (3) the highest-priority research that is needed in order to reduce the key policy-relevant uncertainties.

Past and present research have provided an understanding of several aspects of the "greenhouse effect", which is due to the absorption of part of the heat that the Earth's surface would otherwise radiate to space by some atmospheric trace gases. The global system thus is warmer than it would be otherwise without the presence of the trace gases.

A better understanding of numerous scientific aspects of global warming can help with policy decisions regarding possible human-influenced climatic change; for example, those scientific points that relate to the following questions:

-What can cause climate change and particularly which humanactivities?

-What are the predicted human-influenced climatic changes, and how do they compare with natural ones?

-What is the degree of confidence in current predictions of climatic change?
-Have we seen any human-induced climatic changes yet?

Some things are known about the greenhouse effect with high certainty; others remain very poorly understood. The spectrum of knowledge and uncertainty ranges from unequivocal increases in the atmospheric abundance of carbon dioxide (a "known") to the inability to predict the climatic consequences for a specific region and year (an "unknown").

The focus in this summary is on policy-relevant aspects, namely, those scientific points that relate to the above questions. It is based on the assessments of the state of scientific understanding of climate change that was prepared by the international scientific community in 1990 (and updated in 1992) under the auspices of the International Panel on Climate Change (IPCC), about which I will have more to say below.

A doubling of carbon dioxide levels in the atmosphere within-the next century, compared to pre-industrial levels, is virtually certain. The atmospheric abundance of carbon dioxide is increasing, due largely to the combustion of fossil fuels and biomass by humans. All scientists are convinced of this. The future rate of increase will depend strongly on: (i) how emissions are influenced by technical developments, economic factors, and policy decisions, which cannot be predicted entirely in advance; and (ii) the net absorption of carbon dioxide from the atmosphere by vegetation and the oceans, which is still somewhat uncertain. Nevertheless, essentially all

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