« PreviousContinue »
Mr. HANSEN. Yes, I would like to quickly respond to that. It is a very curious charge, because, in fact, if you look at my 1988 testimony, what I showed was three scenarios for the future. One of them, scenario A, was business-as-usual, in which the emissions increase, every year you have more than before, and the other-scenarios B and C had more flat emissions. In fact, the real-world emissions have been between scenarios B and C. If you look at our climate model calculations for the forcings which have actually occurred, they are right on the money. So Mr. Michaels did a very interesting thing. He took our chart-by the way, in the Senate testimony I said
Senator BENNETT. In the House testimony.
Mr. HANSEN. In my Senate testimony in 1988-
Mr. HANSEN. I testified to both the House and Senate in 1988 and showed exactly the same projections-but I said the most likely scenario is scenario B, not scenario A. But Mr. Michaels took this chart, erased scenarios B and C, and showed scenario A. So it is a very simple answer to this.
Senator BENNETT. I appreciate that, because I suggest or believe that the New York Times has taken scenario A and enshrined it in conventional wisdom forever and ever, as they tell us what scientists are saying. I appreciate your clarifying that, because what you are saying is that there is no absolute certain prediction upon which everybody can depend with respect to the future. There is a great deal of uncertainty.
Mr. HANSEN. That is exactly right. There is no reason that we need to follow scenario A, the business-as-usual.
Senator BENNETT. You are saying now that we did not follow the scenario
Mr. HANSEN. We have not, no. I mentioned a little earlier that, in fact, the growth rate of emissions declined 25 percent in the last two decades because of chlorofluorocarbons being phased out and because of methane slowdowns. So we have already taken some very helpful steps for reducing the future climate change and we need to take some more in the next century.
Senator BENNETT. I would hope that if there is any representative of the New York Times here, that they would call your answer to the attention of their editorial writers, so that they could become a little less hysterical.
Mr. HANSEN. I actually tried to do that. I wrote an op-ed article a week ago, but they did not publish it.
Senator LIEBERMAN. We can sympathize with that. [Laughter.] Senator BENNETT. You will not get opinions that are not fully orthodox ever reported in the New York Times, unless you can get Bill Sapphire to write the column about it.
Chairman LIEBERMAN. That explains why I like those editorials, they are fully Orthodox. [Laughter.]
Senator BENNETT. Very good. You have maybe answered this question, but I would like you to get into it a little bit more. We are talking about temperatures going up in the last 100 years. In fact, they went up for 30 years. They went down, admittedly at a
started up again for 30 years. So, instead of this being the chart for the last century, it is this, this, and this. [Indicating.]
Can you tell us what caused that 30 years of temperature going down, roughly between 1945 and 1975?
Mr. HANSEN. We cannot do it with confidence. It could be unforced variability. The climate system is a chaotic system, which fluctuates from decade to decade, just like the weather fluctuates from day to day, because the atmosphere and ocean are fluids, which are chaotic and have an unforced variability. It could also have been forced. As you know, as we have talked some time today, there are both positive forcings and negative forcings, and the negative forcings probably the aerosols have not been increasing so much recently. In fact, in the United States and Europe, they have been decreasing because of acid rain concerns. It could be that the aerosol increases caused that cooling trend, but we do not have the measurements to prove that.
Senator BENNETT. You are underscoring once again the uncertainty here.
Mr. HANSEN. Right.
Senator BENNETT. We do not really know what caused it to go up so rapidly in that first 30-year period or what caused it to come down in 30 years. We think we have got a better handle on what is causing it to go up now, but even there, we cannot be absolutely sure. Is that a fair statement?
Mr. HANSEN. That is exactly right.
Senator BENNETT. One final question. As I looked into this, I asked a layman's question and was a little stunned at the answer that I got. I hope you can help me understand it. I said, “How much CO2 is there?" We talk about CO2. How much CO2 is there and what percentage of it comes from human activity? I am told that roughly three-maybe generously 4 percent of the total CO2 that the planet has released into the atmosphere every year comes from human activity, and that the rest of it is all generated by the planet itself.
My question is, is there a difference out there in the atmosphere or troposphere or wherever it is you wander, between naturallygenerated CO2 and human-generated CO2? Let me tell you why I want to know that. Because if indeed there is no difference-let's take the 4 percent number, which is the largest number I have heard for human activity generating CO2, and take the 25 percent figure, which the New York Times quotes as coming from the United States, that means the United States is producing 1 percent of the total CO2 out there, and if we do Kyoto, we reduce that by less than 1/10 of 1 percent. I wonder why savaging the American economy to reduce the total by less than 10 of 1 percent is a good idea.
Now, that is where the math is. Once again, is there a difference in the atmosphere between naturally-generated CO2 and humangenerated CO2 that affects this whole equation?
Mr. HANSEN. There is not a difference which is relevant to their ability to cause warming. However, I do not understand where your 4 percent comes from, because there are various ways to do these
Senator BENNETT. It comes from the Department of Energy and cross-checked with the Congressional Research Service at the Library of Congress.
Mr. HANSEN. Let me tell you what I think the relevant numbers would be. Prior to the Industrial Revolution, the amount of CO2 in the atmosphere was about 280 parts-per-million. It did change over time scales of tens of thousands of years with the Ice Ages and things, but the last several thousand years it was about 280 partsper-million. It is now about 360-is that right, Mr. Karl? So it is about a 25- or 30-percent increase, and we are pretty darn sure that that is almost entirely due to human activity. So, based on those numbers, it is not a 4 percent increase. It is more like a 30 percent increase, and the United States has contributed a fairly large fraction of that.
Senator BENNETT. Clearly, we need a resolution to this, because I have gone to every source I could find to say what percentage of the total CO2 currently being sent into the atmosphere comes from human activity, and the answers have been amazingly uniform.
Mr. HANSEN. The way you get that small number is to look at the fluxes. There are fluxes that go up and down, because the plants are growing and decomposing-there are fluxes up and down. But the point is, if you look at those total fluxes, yes, the human contribution may not look so large. But the net impact of that human contribution-it is always one sign. Humans are the cause almost certainly for almost all of this increase from 280 parts-per-million to 360 parts-per-million.
So I think it is more appropriate to say that humans have contributed an increase to atmospheric CO2, which is about 30 percent of what is there now. There is really no scientific disagreement about this.
Chairman LIEBERMAN. You got your answer, Senator Bennett. Senator BENNETT. I will go back to the Department of Energy and the Library of Congress now and see what comment they have. Chairman LIEBERMAN. Thanks very much. You raise some important questions, including the ones about the economic consequences of Kyoto, which I believe that some of our witnesses on the second panel will testify to. If they do not, I am going to ask them about it. Thanks to both of you.
Did you want to respond at all, Mr. Karl, to Senator Bennett's questioning?
Mr. KARL. I might just want to make one statement, and that is absolute certainty is very rarely going to be found in these complex environmental issues. So when we say we are nearly certain, that is pretty high statement coming from scientists in an area that is fairly uncertain.
Chairman LIEBERMAN. Thanks very much to both of you. I would like to now call the final panel: Eileen Claussen, President of the Pew Center on Global Climate Change; Dr. James Edmonds, Senior Staff Scientist, Pacific Northwest National Laboratory, Battelle Memorial Institute; Dale E. Heydlauff, Senior Vice President, Environmental Affairs, of the American Electric Power Company; Jonathan Lash, President of the World Resources Institute; and Margo Thorning, who is Senior Vice President and Chief Economist of the American Council for Capital Formation.
Thanks to all of you for coming this morning. We really look forward to your testimony about the Byrd-Stevens legislation and about the problem overall.
Ms. Claussen, welcome back.
TESTIMONY OF EILEEN CLAUSSEN,1 PRESIDENT, PEW CENTER ON GLOBAL CLIMATE CHANGE
Ms. CLAUSSEN. Thank you very much, Mr. Chairman and Members of the Committee. Thank you for this opportunity to testify on S. 1008, the Byrd-Stevens Climate Change Strategy and Technology Innovation Act of 2001. My name is Eileen Claussen and I am the President of the Pew Center on Global Climate Change. The Pew Center on Global Climate Change is a nonprofit, nonpartisan and independent organization dedicated to providing credible information, straight answers and innovative solutions to the effort to address climate change. Thirty-six major companies in the Pew Center's Business Environmental Leadership Council, most included in the Fortune 500, work with the center in assessing the risks, challenges and solutions to climate change. There is a list of who they are up there on the chart.
Mr. Chairman, I believe that enacting the Byrd-Stevens bill will be an important first step in developing a serious domestic climate change program, a step that should be taken quickly. This bipartisan bill will integrate our energy policy with the long-term goal of stabilizing atmospheric greenhouse gas concentrations. It will respond to concerns often raised by other nations that the United States has no basis for domestic action. It will continue investigation into the uncertainties of the science and economics of climate change.
Most important among the many provisions of the Byrd-Stevens bill is the one that requires the development within 1 year of a U.S. climate change response strategy with the objective of stabilizing greenhouse gas concentrations. To meet this goal, the strategy will rely on emission mitigation measures, technology innovation, climate adaptation research, and efforts to resolve the remaining scientific and economic uncertainties.
At the Pew Center, we believe enough is known about the science and environmental impact of climate change for us to take action now. As we have learned from the Intergovernmental Panel on Climate Change, confirmed recently by the National Academy of Sciences, the scientific consensus is very strong that greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise.
As a consequence, there likely will be substantial impacts to human health, agriculture, ecosystems and coastlines. The high probability of these outcomes indicates the need for some action now. Even as we act, however, we need to refine our scientific understanding, particularly on the impacts of climate change. But the best scientific evidence tells us that we have already bought a changed climate, to which we and our children will need to adapt.
Obviously, the more quickly we mitigate, the less we will have to adapt. But some amount of adaptation appears inevitable. The Byrd-Stevens bill creates a sound basis for giving priority to and investigating how we must adapt to climate change. We also applaud efforts to further analyze the uncertainties regarding the economic impacts of climate change. Work done by the Pew Center suggests that no existing model accurately predicts the economic effects of any given measure to mitigate climate change. We are hard at work to fill in many of the gaps of the models, but additional efforts would be most welcome.
Second, the Byrd-Stevens bill will promote technology innovation. In May, Senator Byrd said from the Senate floor that to address global climate change, "What is required is the equivalent of an Industrial Revolution." We think he was exactly right. To effectively address climate change, we need to lower carbon intensity, become more energy efficient, promote carbon sequestration, and find ways to limit emissions of non-CO2 gases. This will require fundamentally new technologies, as well as dramatic improvements in existing ones.
New, less carbon-intensive ways of producing, distributing and using energy will be essential. The redesign of industrial processes, consumer products and agricultural technologies and practices will also be critical. These changes can be introduced over decades as we turn over our existing capital stocks and establish new infrastructure. But we must begin making investments, building institutions and implementing policies now.
Third, under the Byrd-Stevens bill, the climate change response strategy will be required to incorporate mitigation approaches to reduce, avoid and sequester greenhouse gas emissions. This will force us to take a hard, needed look at our policy choices. We believe that it will be extraordinarily difficult, if not impossible, to muster the kind of sustained effort needed to reduce, avoid and sequester greenhouse gas emissions without the force of legally-binding commitments.
There is little incentive for any company to undertake real action unless ultimately all do and are in some manner held accountable. Markets, of course, will be instrumental in mobilizing the necessary resources and know-how. Market-based strategies, such as emissions trading, will also help deliver emissions reductions at the lowest possible cost. But markets can move us in the right direction only if they are given the right signals. In the United States, those signals have been neither fully given, nor fully excepted.
Three decades of experience fighting pollution in the United States have taught us a great deal about what works best. In general, the most cost-effective approaches allow emitters flexibility to decide how best to meet a given limit, provide early direction so targets can be anticipated and factored into major capital and investment decisions, and employ market mechanisms to achieve reductions where they cost least. To ease the transition from established ways of doing business, targets should be realistic and achievable. What is important is that they be strong enough to spur real action and to encourage investment and development of the technology and infrastructure needed to achieve the long-term