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Chairman CALVERT. Thank you, Doctor. Next, Dr. Patrick Michaels is Professor of Environmental Studies at the University of Virginia in Charlottesville and is a Senior Fellow at the Cato Institute. Doctor, you may begin your testimony.

TESTIMONY OF PATRICK J. MICHAELS, PROFESSOR,
ENVIRONMENTAL STUDIES, THE UNIVERSITY OF VA

Mr. MICHAELS. I would like the lights brought down, if we could, because I'm going to show a couple of slides with my testimony. Thank you for soliciting my testimony, by the way. Appreciate it. What testimony?

[Lights turned off.]

I have been asked specifically to comment on the climatic affects of current proposals for greenhouse gas emission reductions. I will examine the currently debated position, a reduction to 1990 levels, somewhere between here, 2008, and 2012, but I cannot do that until we decide what type of model scenario the future will bring. [Slide.]

The first slide is from the United Nations 1990 Report on Climate Change, and it says, when the latest atmospheric models are run with the present concentrations of greenhouse gases, their simulation of climate is generally realistic on large-scales. This suite of models predicted at this time that the globe's mean temperature should have risen between 1.3 and 2.3 degrees Celsius. These models served as a basis for the Framework Convention on Climate Change signed in 1992.

Nearly 10 years ago, I first testified on climate change in the House of Representatives. At that time, I argued that the forces of dramatic and deleterious warming were likely to be erroneous forecasts because of the very modest climate changes that had been observed to date. Further, it would eventually be recognized that the more moderate climate changes would be directed primarily into the winter and the night, rather than the summer, then this could be benign or perhaps even beneficial. I've testified to the likely warming based upon the observed data. It would be between 1.0 and 1.5 degrees C for doubling the natural carbon dioxide greenhouse effect. The next slide, please.

[Slide. See Figure 1 of Dr. Michael's prepared testimony.]

Since that first testimony, the Earth mean temperature has not changed a bit. These are temperatures measured by weather balloons between 5,000 and 30,000 feet. The surface measure temperature of the Intergovernmental Panel on Climate Change, which is the top, and the satellite.

[Slide.]

By 1995, in the next slide, the IPCC admitted the validity of the critics' position. "When increases in greenhouse gases only are taken into account, most climate models produce a greater mean warming than has been observed to date, unless a lower climate sensitivity is used. There is growing evidence that increases in sulphate aerosols are counteracting the warming." IPCC now leaves us two alternative hypotheses while admitting that the critics were right after all. They are saying either the base warming was simply overestimated or something is hiding the warming.

Are sulphate aerosols hiding the warming? Several attempts have been made to demonstrate this, most prominently in Nature Magazine on July 4, 1996. The next slide shows this result.

[Slide. See Figure 2 of Dr. Michael's prepared testimony.]

This particular slide used annual weather balloon data from 1962 through 1987, which are the solid circles, and you can see a rather large warming in the Southern Hemisphere, here, which really drove this correspondence between this model of sulphate and greenhouse effect and the temperature. However, when the entire record of temperature that exists is used between 1958 and 1995, as you can see, the most pronounced region and the region in this model shows no warming whatsoever. The default option that it's simply not going to warm up as much as earlier projections had indicated becomes increasingly attractive. A new suite of climate models, which now seem to fit the data more accurately, bear witness to this conclusion. This is shown on the next slide.

[Slide. See Figure 3 of Dr. Michael's prepared testimony.]

This is the slide with the new model from the U.S. National Center for Atmospheric Research, as shown in the May 16th issue of Science Magazine. Now, a little note on the nature of observed change. The greenhouse physics predicts the driest air masses should respond first and most strongly to changes in human activities. These are, in fact, the very, very coldest air masses on the planet. Let's take a look at the satellite data and see what it found. The next slide shows the satellite temperature history from when it begins in 1979 to now.

[Slide. See Figure 4 of Dr. Michael's prepared testimony.]

Unlike some of my other government scientists, I don't draw trend lines through the data unless they are statistically significant. There is a statistically significant cooling in the satellite record since it began in 1979. The next slide shows something very interesting.

[Slide. See Figure 5 of Dr. Michael's prepared testimony.]

It divides the satellite record into latitude bands. This is the North Pole, this is the equator, and this is the South Pole. And what you can see is a pronounced warming of the mid-latitude land areas of the Northern Hemisphere. That's where the coldest air masses, the Siberian Express and the very cold air masses of northwestern North America dominate the temperature change. Everywhere else there is either no change or it is cooling. By the way, the scientists who said, 30 years ago, that the planet was undergoing a slight cooling trend still remain correct in this respect. We may have superimposed a slight greenhouse warming in the mid-latitudes of the northern hemisphere but the overall trend remains slightly negative. Another way to appreciate this satellitethe temperature changes-is to look at a longer surface temperature record, which is the next slide.

[Slide. See Figure 8 of Dr. Michael's prepared testimony.]

Here what I've done is I've taken the temperature changes measured since 1950 in the winter and subtracted the changes in the summer. The redder it is, the more you can see that the coldest, most obnoxious air masses that we know of have warmed up and this is the signal that emerges from the data. Next slide, if we can go over two slides and I want to see-well, actually, let's not. I

have just enough time to finish, I think. I talk fast, I'm sorry. The question has come up as to how good the satellite data is and I want to show you a very stringent test of this data before I conclude my testimony.

[Slide. See Figure 7 of Dr. Michael's prepared testimony.]

This is the satellite temperature trends between 1979 and now, taking the winter warming and subtracting from it the summer warming. It isolates out the fact that almost all the warming is in these extremely cold air masses in the winter. The bluer it is, the colder it's gotten. The next map is the surface temperature record. If you take a look, the correspondence is absolutely phenomenal between these two records. Next slide.

[Slide. See Figure 9 of Dr. Michael's prepared testimony.]

This is where I would like to conclude. As noted, I think, by now, the most likely explanation for the now-acknowledged warming deficit is that the sensitivity of global temperature to greenhouse effect changes was overestimated.

A very few-I would like to show you now what would happen with the current proposed program because I think we now can agree that there was an overestimation. This new climate model that you see here is from the National Center for Atmospheric Research. It does not contain, what are called in Science Magazine by Richard Kerr, fudge factors that make the model transport more warming northward than would occur in reality. All previous models have been adjusted arbitrarily to give the right answer. This one was not. You'll notice something very interesting. When we put in the medial emissions scenario for the United Nations Intergovernmental Panel on Climate Change, something known as "business-as-usual," we get much less warming in this model on out for the next 50 years. Between 1990 and now, a warming of about, it's in the table here, in your testimony, no, it's not. It's the warming of about four-tenths of a degree, something like that. Now, if the entire world went along with the President's program, not just the United States, the entire world, including China, India, and the developing world, we can calculate how much the change in emissions in the atmosphere would be and take this model and translate it into the temperature change. Behold the warming that is saved over the next 50 years. Ladies and gentlemen of the House, ladies and gentlemen assembled here, the amount of saved warming is 0.13 degrees Celsius. That amount is so small it could not be measured by the surface temperature thermometers on the planet. However, it would be measured by the satellite. Thank you very much. [The prepared statement and attachments of Mr. Michaels fol

Testimony of:

Patrick J. Michaels

Professor of Environmental Sciences

University of Virginia

and Senior Fellow in Environmental Studies at Cato Institute

to:

Subcommittee on Energy and Environment of the Committee on Science United States House of Representatives

November 6, 1997

Testimony of:

Patrick J. Michaels, Professor of Environmental Sciences, University of Virginia, and Senior Fellow in Environmental Studies at Cato Institute

to:

Subcommittee on Energy and Environment of the Committee on Science
United States House of Representatives

November 6, 1997

Thank you for soliciting my testimony on climate change. Specifically, I have been asked to comment on the climatic effects of current proposals for greenhouse gas emission reduction. I will examine the currently debated position, a proposed reduction of emissions to 1990 levels sometime during the period 2008 to 2012. However, before such examination can be made, it is necessary to decide on what model or scenario best describes the future climate.

Historical Background

The First Scientific Assessment of the United Nations Intergovernmental Panel on Climate Change (IPCC, 1990), stated that "when the latest atmospheric models are run with the present concentrations of greenhouse gases, their simulation of climate is generally realistic on large scales." (1) The suite of climate models extant at the time predicted that the globe's mean temperature should have risen by 1.3°C to 2.3°C, with the larger figure for the Northern Hemisphere, where most of us live. These models provided the technical background for the Framework Convention on Climate Change, signed in 1992.

Nearly ten years ago, I first testified on climate change in the U.S. House of Representatives. At that time, I argued that forecasts of dramatic and deleterious global warming were likely to be in error because of the very modest climate changes that had been observed to that date. Further, it would eventually be recognized that this more moderate climate change would be inordinately directed into the winter and night, rather than the summer, and that this could be benign or even beneficial. I testified that the likely warming, based on the observed data, was between 1.0°C and 1.5° C for doubling the natural carbon dioxide greenhouse effect.

Since that first testimony, the global mean temperature of the earth has not warmed a bit. Three independent measuring systems-surface measured temperature, temperature of the lower

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