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I do not think it is going to be that simple because some of the fundamental measurements have not even been made yet.

It does allow me to make a point that, it is not just computer power, it is the symbiosis among computing power, human intellectual brain power, and very hypothesis testing measurements that allow progress to happen. And computer modeling becomes a way to test hypotheses because they make predictions that can be evaluated and critiqued.

Mr. MINGE. Dr. Michaels, I would like to ask you if you feel that the consumption of fossil fuels is irrelevant to questions of global warming.

Dr. MICHAELS. No. Absolutely not.

Mr. MINGE. So we are presented here, as I understand it, with a situation where there are models that indicate a certain level of global warming and I think that all three members of the panel have agreed that there is some level.

And a question of what we should do as a country and what we should do in combining with other countries to address potential adverse effects.

Mr. ROHRABACHER. Would the gentleman yield for just a moment?

I think also another question along that line is whether or not the global warming is a product of man-made activity.

Mr. MINGE. Well, I will let you come back with whatever misgivings you have about this.

But the question is whether we should attempt to address the situation by changing our consumption of fossil fuels and other lifestyle factors.

And I would like to ask you, Dr. Mahlman, to take off your scientific hat, if you are comfortable doing that, and as a person who has devoted many years to this study, share with us any recommendations that you would make as a private citizen so that we have a little bit better understanding of public policy directions that you would recommend.

And I say this in all sincerity because here you are, employed by the United States of America to do this. You are not being paid by any environmental group, you are not being paid by any industrial group, and we rely upon you to be fairly objective about it.

And we do not want to wait until every last uncertainty is eliminated before we act. We have to make some decisions when there are still some uncertainty in the situation.

So with those comments, I would appreciate your response.

Dr. MAHLMAN. I have said in these halls before that I have noticed that it is a lot easier to criticize your congressman than to be a congressman. And this is a good example of why.

I personally believe that I have given you a no ideological spin on the ball assessment of where the science is on this. And what I see, as a citizen, that this is an extraordinarily nasty place to be in if you are a policymaker. Because if you look at the problem and you try to do something about it now, I think objectively you can say that the cost of doing something about it that makes a big dent in the problem is extraordinarily high.

The cost of not doing something about it is probably also extraordinarily high. And so I do not think there is a safe landing spot.

I do not think that any specific recommendations I would make that do, as you do, take cognizance of all of the competing factors gives you a simple, easy thing to deal with.

As I said in my testimony-and you were not here at that time— is that I do not think that no matter what we say or do in the next five years, the problem's going to either be solved, or it is not going to go away. And so I will duck the question in that sense.

Although I do believe that it is my responsibility, as a scientist who is employed by the government, to be absolutely non-ideological, that we can speak to the questions that you have to address. But the answers to those questions are fundamentally, as so often what you do, values debates and values issues, not science issues. Mr. MINGE. Has the state of the art in science advanced beyond the leech stage in medical technology that we had maybe a century or two ago?

Where do we stand in terms of the assistance that we can expect from the scientific community in answering some of these questions?

Dr. MAHLMAN. I would argue that the state of scientific understanding on this problem is demonstrably superior to the state of intellectual understanding on almost anything you vote on that you argue a lot about. Okay?

[Laughter.]

Dr. MAHLMAN. Respecting the degree of difficulty, and I have made the statement that if, for example, that we were to become infinitely wise, and Patrick Michaels and I could agree on all the points and we know how the climate system works and how it is going to change, we could lay that information out on the table for you, and you would still have a miserable problem as to how to deal with it as a society and as a planet.

Mr. ROHRABACHER. I think that we should-Mr. Doyle is next up, and

Mr. MINGE. Thank you.

Mr. ROHRABACHER. Thank you, Mr. Minge.

Mr. DOYLE. First of all, thanks for recognizing me, and I apologize for missing the testimony of the panelists.

Those of us who are lay people I can tell you are fascinated by this whole discussion. And I do not know if it has been addressed already, and if it has, I will just shut up and we can move on to the next speaker, but just as a lay person, we read a lot about global warming.

Is there a consensus in the scientific community that we are going to have this global warming on the order of one to four degrees? That that is actually something that is going to happen? Or is there a wide disparity in views?

Is there any consensus on this, and has that been touched on earlier?

Dr. MAHLMAN. I would argue that there is a substantial consensus, and that Dr. Michaels will contest that-that is true.

Dr. MICHAELS. No, I did not. He said one to four degrees. I think that the databased, and now the model/databased arguments, that are coming out in the literature put you in the one to one-and-ahalf degree range for effective CO2 doubling after all is said and done.

You know, the problem is that the bottom number that you are talking about there over a hundred years is not something you are going to want to spend a lot of money doing anything about, especially if it really translates mainly into shorter winters and longer growing seasons and is in the winter. Characteristics that, by the way, we seem to see emerging from the data.

The higher numbers is a big problem. And one of these days, I think we are actually evolving towards a solution.

But something in the previous question to you, Jerry, I have to touch back on, to show how difficult this problem is.

We have measurements, accurate measurements of temperature in the atmosphere that are done by weather balloons twice a day. People really like these records because these are calibrated instruments. They go back into roughly the 1950s or so. The record by Oort I think goes back into 1962.

And if you look at that record, you see a warming in it. And everybody goes, "Wow, global warming by the best record we can find."

Then if you look at the record carefully, you see the following: There is no net change in temperature from 1977 through 1994; and there is no net change in temperature from when the record begins Oort's record in 1965 to 1976. So that says that all that warming occurred statistically in one year.

Now the question I have is, are we ever going to have a climate model that is going to be so good that it could pick something like that out?

Mr. GUERRERO. If I could provide our observations?

One of the things we looked at, when we looked at the uncertainty range associated with the model predictions, is what kind of models are there out there.

And one point that I think is worthwhile keeping in mind, Dr. Michaels pointed to today in his slides, a particular model and the variance between what that model predicted and the actual temperatures that were registered.

That is a model among any number of models. And the important thing to keep in mind in this process is there is a vehicle for looking at the different types of models. Some of them are better than others. And that process is the IPCC process that involves thousands of scientists reviewing and peer reviewing the literature and trying to achieve consensus.

Now it does not mean you are going to get total agreement. It does not mean you will not have scientists who feel strongly on one side or the other of this picture.

But what it does mean is that after having gone through a process of thousands of individuals looking at the records and the model results, that they did reach some level of agreement.

Mr. DOYLE. Yes. And I guess when we get through this whole issue of cost/benefit analysis and, like Dr. Michaels said, if it is one degree, it is one thing; if it is four degrees, it means quite something else. And when we talk about risk assessment and cost benefit analysis here in this Committee, and then look at these models where you see ranges going from 1.8 to 6.3 in one model, or 2.7 to 8.1, it becomes a very confusing dilemma for those of us who are trying to decide, you know, do we have a situation here that we

need to be paying serious attention to and doing something now, or is this something that is in the range of one degree over a hundred some years, and it is not prudent to spend money.

So

Mr. ROHRABACHER. Could I ask a question that fits into the point that you are making, because you were not here the entire time. Is there a consensus that as we get better information because of better technology that is available to us, is this the consensus that actually that the degree of global warming has come down? And I believe there is an EPA report that just suggested that? Or am I incorrect in that?

Dr. MAHLMAN. I think Dr. Michaels and I would have a different perspective about that.

I think that the prediction of what will happen to the climate has gone down because of our increased understanding of offset due to sulfate aerosols. Okay? And that is not necessarily a statement about what the model said or did not say. What it is saying is there was an effect that was not calculated in the models that looked only at carbon dioxide.

So that is my answer.

Mr. ROHRABACHER. Now, in 1991, let me ask, and my staff is suggesting now that you ranged your estimates in 1991 that global warming would be between two degrees and eight degrees, and today you are testifying that global warming will be between two degrees and six degrees, is that correct?

Dr. MAHLMAN. No. I had smaller numbers than that. Because in 1991, I was answering a different question. Okay? In 1991, I was answering the question that was asked, is, "What is the equilibrium changed to a double carbon dioxide expressed in degrees Fahrenheit?"

Today we are asking a different question. What do we expect roughly in the middle of the next century at the time of approximate onset of the equivalent of doubling carbon dioxide if the sulfate part does not change?

It is hard to answer you because

Mr. ROHRABACHER. I do have a copy of your testimony and it does say that for the middle of the next century, global mean surface warming is estimated to be in the range of two to eight degrees, and that is, I am not sure if that is inconsistent with what you are saying.

Dr. MAHLMAN. That is pretty consistent with what I said, yes. Mr. ROHRABACHER. Okay. Well, I am sure somebody else understands

Dr. MAHLMAN. You have got to remember that is in Fahrenheit, not centigrade.

Dr. MICHAELS. Mr. Chairman, what Dr. Mahlman is saying is, he said there has been a decrease in the forecasts because of sulfate being applied to the model.

And what I have been publishing in literature is that the sulfate explanation, which results in a reduced warming, is not sufficient explanation for the lack of warming. That there are other things going on here.

That is where, I do not know, do you think it is just sulfates? Is that the only thing that is caused the disparity in the GFDL model?

Dr. MAHLMAN. Well, if you wish to talk about the GFDL model, I certainly can speak to that.

You compared apples to oranges in your time series in that you looked at a GFDL model which is looking at the transient effect of an increased one percent per year of carbon dioxide increase, and you compared it to the last 15 years which has an offset of sulfate aerosol, and also has an offset due to stratospheric ozone reductions that led to cooling in the upper troposphere, and so I do not think that that was a fair comparison at all.

Mr. ROHRABACHER. We already touched upon that. Maybe we can have Mr. Cramer who

Mr. DOYLE. That clears everything up for me. Thank you. [Laughter.]

Mr. ROHRABACHER. If Mr. Cramer would like to follow through on this part of the discussion, we would be pleased to have him do so, if he would like.

Mr. CRAMER. Thank you, Mr. Chairman.

What an interesting time.

I just came in, and I certainly do not want to confuse anyone, so I will pass for now.

[Laughter.]

Mr. ROHRABACHER. Mr. Olver is hiding back there, and he has never passed up an opportunity to confuse us.

[Laughter.]

Mr. ŎLVER. Thank you, Mr. Chairman.

I usually start at these things confused and end up even more confused.

But in any case, I also just came in. I came in at the point of hearing Dr. Mahlman's comment and I think that while it may be true that in most areas of science, the degree of understanding is better than what we seem to be arguing about here in most areas of social policy or the application of science to social policy.

I get the impression that the science is, at least among those who are practitioners in this area, are nearly as, the range of opinions is nearly as wide as it is in our arguments about the use of it here. So I was struck very curious about the comments by Dr. Michaels and I wish you would go through this again.

Please tell me again what it was that you compared two long ranges of years in which nothing had happened, though the sum total appears to show a substantial change that would lead one to believe that all that change had occurred in one year.

Dr. MICHAELS. Right.

Mr. OLVER. That is a paraphrasing of what I understood while I was half listening while trying to read some of the testimony, and I do not understand how that can happen.

Dr. MICHAELS. Okay, I will show you.

Mr. OLVER. And maybe in the result of it, you will need to show me exactly where

Dr. MICHAELS. I have a slide in there that will show it and it will show it much-the picture says ten thousand of my poorly chosen words.

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