world's and one of humanity's greatest challenges, we must begin now. Mr. Chairman, I again thank you for holding this hearing. I again thank my colleague, Senator Stevens, for his vision, his leadership, for his cooperation, for his joining in the promotion of this legislation. I look forward to working with you, Senator Lieberman, and with you, Senator Thompson, Senator Stevens and the other Members of this Committee on this important and timely legislation. It is not a moment too soon.

I ask unanimous consent that my May 4, 2001 and June 8, 2001 climate change statements printed in the Congressional Record be made a part of the record.1

Chairman LIEBERMAN. Without objection.

Senator BYRD. That completes my statement, Mr. Chairman. Chairman LIEBERMAN. Thank you very much, Senator Byrd, for a very thoughtful, very important statement, and one that has, I think, the appropriate sense of urgency.

Senator Stevens.

OPENING STATEMENT OF SENATOR STEVENS

Senator STEVENS. Well, thank you very much, Mr. Chairman, and I, too, join Senator Byrd in thanking you for holding this hearing, and I commend my good friend from West Virginia for his leadership in trying to establish a major research effort to reduce carbon emissions and deal with the whole subject, the myriad of subjects that are included in global climate change strategy. I thank you very much, Senator Byrd, for allowing me to join you on this, because it is a matter of great importance to me and my State, as you know.

I think, Mr. Chairman, Senator Thompson, Members of the Committee, in days gone by, Senator Byrd and I might have just added this to an appropriations bill.

Chairman LIEBERMAN. We still were hoping that eventually you might do that. [Laughter.]

Senator STEVENS. The difference is that we know this is such a complex subject, one that needs congressional approval before we forge into this area. We want to make sure that you are all behind us before we try to put the taxpayers' money where our mouths have been. We need funds for this. I view this as being next to major medical research in terms of issues that this country faces, and I want to tell you I am particularly interested because of the last hearing I chaired, Mr. Chairman, as Chairman of the Appropriations Committee, was a field hearing in Fairbanks on the impacts of global climate change on the Arctic environment.

I would welcome and urge you to think about bringing the whole Committee up to see what global climate change means. There is no question that the change has taken place more rapidly in the Arctic than anywhere else on the globe. Many of the witnesses at our hearing noted that climate activity stems from a number of factors, including human activity. I do not think we can assess it totally to human activity.

The statements submitted by Senator Byrd from the Congressional Record on May 4, 2001

The degree to which any particular phenomenon or activity contributes to climate change is not yet well-understood. Regardless of the cause, there has been a dramatic warming trend in the Arctic areas, as I said. Let me tell you, pack ice, which is the ice that insulates our coastal villages from winter storms, has shrunk 3 percent per year since 1970. Increased storm activity has caused significant beach erosion, which now has required us to consider ways to displace entire communities along the coastline of Alaska.

The sea ice is thinner than it was 30 years ago, and the sea ice is the platform on which most of the reproductive activity of marine mammals takes place. It is back from the shore now. This is permanent ice that is thinning. As a matter of fact, I was told it was three inches thinner this year than last year. The Northwest Passage has been opened now for 3 years. I remember so well, as a young Senator, when I went on the MANHATTAN and tried to accompany many people and see if we could use the Northwest Passage to transport Alaska's oil to the East Coast, rather than build a pipeline; and it failed, as you know, because of the ice.

We spent days riding that ice breaker tanker, grinding three, four, five miles a day of ice. That is gone now. It is not there. The Northwest Passage is just one of the indications. I would invite you to come up and see our northern forests. Our northern forests are now farther north and further west, as the permafrost is melting, and the permafrost melting means a great deal to us. Half of the coal in the United States is in that area, of the permafrost of Alaska. Whether we will ever be required to use it, I do not know, but under current law, we would have to replace the contour of the land if we took the coal out. Of course, that is an impossibility.

Now, the powers-that-be, the Good Lord, is melting that permafrost and the contour may not be the same in future years as it is now. It might be easier to get to the coal. But this legislation provides us a balanced approach to climate change and will help us deal with the issue of greenhouse gases and do so without harming the economy of the United States, and to increase the capability of Third World countries to improve their economy. By making necessary research and development efforts now, I think we can inspire a generation of technologies that will enhance America's chance to be the leader in dealing with global climate change.

It will increase research and development funding, so we can better understand this global climate change. We can plan to develop the capabilities that technology will lead us to, and I think we will be able to react to global climate change in a very positive way if we follow the Senator's lead, and I am glad to be his partner in this effort. This bill will require, in my judgment, that we double the technology investment for research and development related to global climate change, just as we doubled the investment in health research in the last 5 years. This will lead us into a new era of funding for research in this area.

I think there should be no misunderstanding about it, because I have joined Senator Byrd in making a commitment that this money will be made available to the research community, so we can better understand these changes and take whatever actions we can to offset them. It will create a process for the United States to take seri

the hearing, and again I repeat my invitation to you to come up and see what is happening. I was told in Fairbanks that while the world as a whole may have increased in temperature by about one degree, the Arctic has increased in temperature by seven degrees, and we took our committee to Antarctica to see if the same situation was developing down there.

They have increased ice pack down there. They have increased problems down there, but they are not as much involved in global climate change as we are in the Arctic. The Arctic is the place to understand global climate change and I am proud, Senator, that you allowed me to join you in this effort, and pledge that we will fight this battle together. We need this information. We need to develop this technology as rapidly as possible.

Thank you very much.

Senator BYRD. Thank you, Mr. Chairman.

Chairman LIEBERMAN. Senator Stevens, thank you very much for that very compelling testimony, and particularly for the memorable reports from Alaska and the Arctic. I accept your invitation. I think Senator Thompson and I ought to figure out a way to see if we can bring the Committee exactly to the places you described. In a way, it may be that Alaska and the Arctic are the early warning system or, to use an old and worn expression, the canary in the coal mine, in the case of climate change. I thank you.

Senator Byrd, thank you very much for your time. I know you have a busy schedule and I appreciate very much your being here today.

Senator STEVENS. Please excuse me, too. I have another—

Chairman LIEBERMAN. Oh, you have a busy schedule, too. It is always great, not only to have your leadership on a critical problem like this, but to know when we have your leadership, the prospects of funding such a bill are quite high. [Laughter.]

Thank you. We will call the second panel: Dr. James Hansen, Head of NASA Goddard Institute for Space Studies; and Thomas Karl, Director of the National Climatic Data Center. Dr. Hansen, why don't you proceed? We have a clock going. Your full statement, which we appreciate, will be printed in the record in full, and I ask you to try to stay pretty much as close to the 5 minutes as you can. Then it is the tradition of the Committee now to give each Senator 10 minutes. So if any of my colleagues want to make opening statements, that hopefully will give them the opportunity to do that, as well.

Dr. Hansen.

TESTIMONY OF JAMES E. HANSEN,1 Ph.D., HEAD, NASA
GODDARD INSTITUTE FOR SPACE STUDIES

Mr. HANSEN. Thank you, Senator Lieberman. I will talk about options for influencing future climate. The most popular prediction for future climate change is based on the business-as-usual scenario, in which the annual increments of the forcing agents that drive climate change grow larger and larger every year. This sce

1The prepared statement of Mr. Hansen with attachments appears in the Appendix on page

nario leads to a prediction of dramatic climate change, several degrees by the end of the century.

It is a useful warning of what could happen if we let the growth of climate-forcing agents run wild. For the sake of contrast, my colleagues and I have defined an alternative scenario for climate change in the 21st Century. In this scenario, the growth rate of the forcing agents that drive climate change decelerates, such that global warming in the next 50 years is less than one degree and the stage is set for stabilizing atmospheric composition later in the century. How can we achieve this? What are the climate forcing agents?

My chart,1 which is over here, but is also in your handout, shows the estimated climate forcing agents that exist today. Red is used for forces that cause warming, blue for cooling. Carbon dioxide, the bar on the left, causes the largest forcing, 1.4 watts-per-metersquared. But the forcing by other greenhouse gases, the next four bars, adds up to at least as much as carbon dioxide. Methane causes a forcing half as large as carbon dioxide. Tropospheric ozone is also important; and then there are several aerosols, which are fine particles in the air. Black carbon is soot from diesel engines and coal burning. It causes warming. Organic aerosols and sulfates from fossil fuels cause cooling. Aerosols also affect the properties of clouds (that is the large blue bar here) and cause a cooling, but the magnitude of it is very uncertain. The net forcing by all of these is positive, consistent with observed global warming.

The question is: How will these forcings change in the future? The added climate forcing in the next 50 years will be only one watt and greenhouse warming less than one degree provided, (1) we halt the growth of the non-CO2 forcings, and, (2) fossil fuel use and CO2 emissions continue, but at about the same rate as today. The resulting forcing of one watt would cause some climate change, but less than one degree in 50 years.

So, first, can we stop the growth of the non-CO2 forcing? Not only can we, but it only makes sense. Black carbon is the product of incomplete combustion. You can see it in the exhaust of diesel trucks. The microscopic soot particles are like tiny sponges. They soak up toxic organics and other aerosols. They are so tiny that, when breathed in, they penetrate human tissue deeply. Some of the smallest enter the bloodstream. They cause respiratory and cardiac problems, asthma, acute bronchitis, with tens of thousands of deaths per year in the United States, also in Europe, where the health cost of particulate air pollution have been estimated at 1.6 percent of the gross domestic products.

In the developing world, the costs are staggering. In India, approximately 270,000 children under the age of five die per year from acute respiratory infections caused by this air pollution. The pollution arises in household burning of field residue, cow dung, coal, for cooking and heating. There is now a brown cloud of air pollution mushrooming from India. Tropospheric ozone is another pollutant whose growth could be stopped, as could that of methane. We have only one atmosphere and it is a global atmosphere. We need to reduce the pollution that we put into it for other reasons,

human health, agricultural productivity, and in the process we can prevent the non-CO2 climate forcing from increasing.

In the United States, for example, we can reduce diesel and other soot admissions. We might also work with developing countries to help reduce their pollution. One possible long-term solution would be electrification, a clean source of energy.

Now, the other part of the climate problem is CO2. It is the hardest part of the problem, but is not as intractable as it is often made out to be.

In 1998, global CO2 emissions declined slightly. In 1999, they declined again, and, in 2000, another small decline. This is just the trend needed to achieve the alternative scenario with only moderate climate change. In the near-term, my opinion is that this trend can be maintained via concerted efforts toward increased energy efficiency, conservation and increased use of renewable energy sources. On the long-term, we probably need a significant increasing contribution from an energy source that produces little or no CO2.

In my written testimony, I note some possibilities, which include zero-emission coal; nuclear power; the combination of solar energy, hydrogen and fuel cells. Each possibility has pros and cons, and R&D is needed. It will be up to the public, through their representatives, to make the choices.

Finally, the relevance of all this to your hearing is that there is more than one way to control climate change. The forcing agents that cause climate change are complex and, in some cases, poorly understood. These forcing agents have other effects on people and the rest of the biosphere that should be considered. We need to take a broad view of this issue. We will need a strategy, and that strategy will need to be adjusted as we learn more and see the effect of the actions that we take. This is a long-term issue.

Thank you.

Chairman LIEBERMAN. Thanks, Dr. Hansen. Mr. Karl.

TESTIMONY OF THOMAS R. KARL,1 DIRECTOR, NATIONAL CLIMATIC DATA CENTER, NATIONAL ENVIRONMENTAL SATELLITE DATA AND INFORMATION SERVICES, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION

Mr. KARL. Good morning, Mr. Chairman. Thank you for inviting me here today, and Members of the Committee. I have been invited to talk about the science of climate change. First, I want to emphasize two important fundamental issues. First off, there is a natural greenhouse effect. It is real. A small percentage of the atmosphere, about 2 percent, is composed of greenhouse gases. This includes water vapor, carbon dioxide, ozone, and methane. These effectively prevent part of the heat from the Earth escaping and lead to temperatures warmer than what would otherwise be the case.

In addition to the natural greenhouse effect, there is a change underway in the greenhouse radiation balance. Some greenhouse gases are increasing in the atmosphere because of human activities and increasingly trapping more heat. Direct atmospheric measurements over the past 40 or so years have documented a steady