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been talking about are making certain assumptions on the future of emissions of various things that affect the climate. And those are obviously, by definition, extraordinarily uncertain.

Scenario projections might even be more accurate because we're getting into two different things.

Mr. ROHRABACHER. Well, we're talking about something that's either validated or unvalidated in terms of the actual assumptions. The reason I'm bringing this up, and let me put this to you, and that is that in articles in the Wall Street Journal and the New York Times, Washington Post, and all of these have been written in the last two months, but this is true before, as well, the word "prediction" is used.

Now isn't this misleading? Isn't this something-we, I've been reading all kinds of predictions, as I mentioned in the beginning of this hearing, that says that, "You know, we're going to be inundated with, our coast lines are going to be inundated," that people are going to be dying of malaria. I mean these were dire predictions.

After this testimony today, I am not leaving this hearing today feeling that those predictions were justified.

Dr. MAHLMAN. Well, I would argue that those are not "predictions;" that what they are is "projections" based upon current behavior.

Mr. ROHRABACHER. But they are using the word "predictions.”

Dr. MAHLMAN. Well, all I can say is I agree with you. I would not use that word because there's a very uncertain sociological scenario that is implicitly wired into those kind of things, and what we in the climate modeling community are trying to do is to ask the most intelligent questions about how we understand the climate, and that's a very different thing than predictions.

Mr. ROHRABACHER. I'll show you why this is important. In an editorial in the Atlanta Constitution on October 12th, this is one of the leading newspapers in the country, it's "predicted" that Savannah, Charleston and New Orleans will be inundated, you know, unless there is a massive seawall that's built.

Now if this society starts building seawalls, and then we find out and we spend hundreds of millions, if not billions of dollars building seawalls, and they're not necessary, what we're not doing is using that money to build bridges and to build things that are, to build infrastructure that is absolutely necessary.

That's why the difference between "prediction" and "projection" is really important because it leads people to make policy decisions like that.

Dr. MICHAELS. Mr. Rohrabacher, I would submit that everybody who wrote the word "projection" knew that it would be turned into the word "prediction." I don't think people are that naive.

And, as a result, I would conclude, along with your scenario about seawall building in Savannah, that if we are not very, very careful on the issue of global warming, we are going to run the credibility of American science into the ground.

We have to be very, very careful about the difference between scenarios and forecasts, predictions and projections, and models and reality.

Mr. ROHRABACHER. One last note.

EPA recently released a report making new estimates in terms of sea level rise, which are considerably lower than the last estimates. And I understand that the EPA deliberately did not use models for this study.

And do we know anything about that, Dr. Guerrero?

Mr. GUERRERO. I'll take the doctor title, that's fine.

The EPA did not use, they started with the IPCC model ranges as essentially, my understanding is, as a strawman, to get a panel of experts to then come up with what they felt were the most likely kinds of scenarios that they could model.

And so the outcome was not indeed then, based on the models themselves, but based on expert judgment.

Mr. ROHRABACHER. Because maybe they don't believe in the models?

Mr. GUERRERO. Well, they admit that the models have some limitations. It's not that they don't believe them so much is that they recognize their limitations, and the EPA felt that they needed to present the full range of probabilities associated with sea level rise. Which brings me to the earlier point that you were making, is that I think when the Atlanta Constitution and others called these kinds of estimates "predictions," they are indeed perhaps exaggerating the case because there's a high degree of uncertainty with all these events.

And presenting a probability range of events is more important, and that's what the EPA tried to do. And I think when they talk this afternoon on impacts, they'll explain why they chose that particular approach.

Mr. ROHRABACHER. I'd like to thank all the members of our first panel, and let me just note just one little thing that Dr. Michaels said earlier might have escaped many of us in the room, but it didn't escape me.

And that is that if, a hundred years ago, we were actually trying to calculate what was going to happen in the future, we'd be calculating that Washington, D.C. would be, and all of our major cities would be destroyed by bacteria that was created by huge mounts of horse manure. And mankind has a way of adapting and has a way of developing new technologies that I believe may well, if there is a global warming problem, may well change the scenarios, even without massive government intervention in just the way things are made more efficient.

There are people today who are developing fuel additives that I know about, and that we will hold hearings on in this subcommittee that make the gasoline engine dramatically more efficient. And that in itself will have a major impact that will be calculated perhaps ten years down the road.

We're not sure if solar energy, and we've had some great research going into solar energy. And, again, this chairman has supported solar energy research, and we've seen some real progress in that in the last few years.

So just a bit of optimism. Quite often what I hear at the end of some of these hearings is that everybody should just give up and we might as well go home because the world is going to end. And there's a lot of reasons for optimism, as well. And we'll talk more about that with the next panel.

And I especially want to thank each and every member of the panel today, and thank you for your time and your patience. And I think everyone enjoyed your testimony.

What we're going to do now is I think what we're going to do is have a break for lunch, rather than basically, or maybe I should wait, we'll wait until the first vote, and then at the first vote, we'll break for a lunch period at that time.

So thank you very much. We'll have the next panel on immediately.

Mr. ROHRABACHER. I've been informed that we are on the edge of a recorded vote, and rather than start-there we go. Why don't we go ahead and do the necessary votes, and come back in half an hour, which is at 15 minutes to 1:00, and that gives everybody time to grab a sandwich.

Thank you very much.

[Whereupon, at 12:15 p.m., the Subcommittee was recessed, to reconvene the same day, Thursday, November 16, 1995, at 12:45 p.m., in the same place.]

[1:00 p.m.]

AFTERNOON SESSION

Mr. ROHRABACHER. This subcommittee is called to order.

Our second panel will address the potential impact of global climate change.

We have with us Dr. Robert Watson, Associate Director of Environment for the White House Office of Science and Technology. Dr. Watson.

And Dr. William Nierenberg, Director Emeritus of the Scripps Institute of Oceanography in San Diego.

David Gardiner who serves in the policy office of the Environmental Protection Agency, and coordinated the recent EPA study of sea level rise, as well as Dr. Thomas Gale Moore, Senior Fellow at Hoover Institution, Stanford University.

Also with us is Dr. Robert Corell, Assistant Director of Geosciences for the National Science Foundation, and chairman of the Subcommittee on Global Change Research.

I would like to thank you all for being with us today. I would like, if possible, if you could summarize your remarks in terms of five minutes. That would be very helpful, because we then-we believe in a dialogue. We will have a dialogue between you, as well as a dialogue with the Members of Congress and the Members of this subcommittee.

Dr. Watson, welcome back. Good to see you again, and would you like to proceed first.

STATEMENT OF DR. ROBERT T. WATSON, CO-CHAIR WORKING GROUP NUMBER II, INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE AND ASSOCIATE DIRECTOR OF ENVIRONMENT, OFFICE OF SCIENCE AND TECHNOLOGY POLICY, EXECUTIVE OFFICE OF THE PRESIDENT

Dr. WATSON. Thank you, Mr. Chairman.

I greatly appreciate being given the opportunity to testify before you and your subcommittee today. Today I am testifying in my capacity as the Co-Chair of IPCC Working Group II.

Hundreds of scientists from academia, government laboratories, environmental organizations, industry, and business representing more than 50 developed and developing countries were involved in preparation of this report.

Let me first, however, summarize the background of the science that you heard this morning, which was the underpinning of this report.

The earth's climate is changing. The earth's surface temperature has increased by half a degree centigrade over the last century and the last couple of decades are the hottest this century.

There is absolutely no doubt that, since the pre-industrial era, human activities have significantly increased the atmospheric concentrations of greenhouse gases, which tend to warm the atmosphere, and in some regions sulfate aerosols which tend to cool the atmosphere.

Climate models that take into account these increases in both greenhouse gases and sulfate aerosols simulate the observed temperature quite well, suggesting that human activities are implicated in the observed changes in the Earth's climate.

There is no doubt that climate will change. It is a question of where, when, and by how much. IPCC Working Group II-1 models project that global mean surface temperature could increase between 1 and 3.5 degrees Centigrade by 2100, and it will be accompanied by a sea level rise of 15 to 95 centimeters, with even larger changes thereafter.

Hence, we expect the incidence of extreme high temperature events, floods, and droughts to increase in some regions.

While we recognize that the reliability of regional scale predictions is still low, this does not preclude an assessment of the sensitivity of human health, ecological and social economic systems to changes in climate.

Working Group II primarily focused on assessing the sensitivity of these systems to changes in temperature and rainfall. This isolates the uncertainty in the impacts' analysis from uncertainties in regional projections of climate change.

Let me quickly discuss the implications of climate change.

We believe there is a new and additional stress on many ecological and socioeconomic systems; that most systems are sensitive to both the magnitude and the timing and rate of climate change; that developing countries are more vulnerable to climate change than developed countries, and unexpected changes cannot be ruled

out.

With respect to human health, we believe most of the effects will be adverse with significant loss of life. Direct health effects include increases in mortality and illnesses due to the anticipated increase in the intensity and duration of heat waves.

We believe the indirect effects are such there will be increases in the potential transmission of vector-borne diseases such as malaria, dengue, and yellow fever, and there could be some increases in nonvector-borne infectious diseases such as cholera.

With respect to food, we believe that global agricultural production could well be maintained in a double CO2 world. However, crop yields and productivity due to climate change will vary considerably across regions and localities.

While the productivity is projected to increase in some areas, such as Canada and parts of North America and Russia, it is projected to decrease in others, especially the topics and subtropics.

Therefore, there may be an increased risk of hunger and famine, especial in the tropics and subtropics where many of the world's poorest people live.

The composition and geographic distribution of many ecosystems will shift, and therefore there will be reductions in biological diversity and in the goods and services ecosystems provide society. Models "project," not "predict".

[Laughter.]

Dr. WATSON. [continuing] that as a consequence of projected changes in climate under a double CO2 world, one-third of the existing forest area of the world will undergo major changes in vegetation type.

We believe that the expected or projected climate change will occur at a rate rapid to which the speed at which forest species grow, reproduce, and re-establish themselves. Therefore, species composition of impacted forests are likely to change. Entire forest systems may disappear, while new assemblages of species and hence new forest ecosystems may be established.

Today, 46 million people per year are at risk of flooding due to storm surges. A one-meter sea level rise would increase this number to 118 million people.

In addition, a 1 meter sea level rise is projected to result in land losses that range from 1 percent for Egypt, 6 percent for the Netherlands, 17.5 percent for Bangladesh, to as much as 80 percent of the Marshall Islands, thus displacing millions of people.

That is the side of the impact.

Can we do anything about it? The answer is, yes, we can do things about it and in a cost-effective way. It does not have to be expensive, as suggested by Jerry Marman of the first panel.

IPCC Working Group II concluded that significant reductions in greenhouse gas emissions are technically possible and can be economically feasible. By utilizing an extensive array of technologies and policy measures together, they accelerate technology development, diffusion, and transfer in all sectors.

For example, numerous studies have indicated a 10 to 30 percent energy efficiency gain above present levels are feasible at little or no cost in many parts of the world over the next two to three decades in industry, buildings and transportation sectors.

It is also technically possible to realize deep emissions reductions in the energy supply sector in step with the normal timing of investments to replace infrastructure and equipment as it wears out or becomes obsolete. That is to say, no premature retirement of capital stock.

Promising approaches obviously include more efficient conversion of fossil fuels from 30 to 60 percent in the world's power plants; switching to low-carbon fossil fuels; decarbonization of fuels followed by carbon dioxide storage; nuclear energy; and, most important, a switch to renewable fuels.

Policies are available to governments that can facilitate that penetration of these less-greenhouse-intensive technologies and can help modify consumption patterns.

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