Global Warming Conference: "Must We Act Now To Avert a Climate Catastrophe?" (Debate)

Global Warming Conference: "Must We Act Now To Avert a Climate Catastrophe?" (Debate)

July 15, 1997

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MR. ADLER: Folks, I guess, wanting to go outside and enjoy the scorchingly hot July Washington afternoon, I don't know if we've actually hit the record today that they were predicting, but I guess some folks decided to take advantage of it.

For the next hour, we're going to two views on what the implications are of current climate science, and whether or not we need to act right now. Moderating this session is Ben Wattenberg, who is a resident fellow at the American Enterprise Institute, and is also a host, as I believe many of you know, of the PBS weekly television series Think Tank, which is on locally, I guess, WETA at 6:00 p.m. on Saturdays. And it's certainly one of the more intellectual talking head shows around, and one that I recommend highly to people.

And now I'll turn it on to Mr. Wattenberg.

MR. WATTENBERG: Thank you, Jonathan.

About a year ago on Think Tank, we did a program on global warming. And, as fate would have it, two of our panelists were Pat Michaels and Alan Robock. It was a -- it was quite a vigorous discussion. It was one of our better programs, although that's hard to be one of our better programs, because all of our programs are wonderful. But we enjoyed that discussion, and I am delighted, I was delighted when I was asked to, in part, recreate that discussion.

Pat Michaels and Alan Robock are distinguished scientists, as you know. Their biographies are in your kit. The order of battle -- it seems to me, by the way, that the question they will be talking about, which is, must we act now to avert a climate catastrophe, is really the central policy question. I'm just looking down your agenda here. Now, I mean, this is the gut question. Do you have to do something now, or can you talk about it for another generation or two? So, it seems to me, we're right on the money on it.

We have allocated 15 minutes to each participant to give an opening statement. At least in Pat's case, I know with slides. And then we will have some back and forth, where your friendly moderator may participate, and then we will try to go to the floor for some questions. And, because we have promised to be out of here in exactly one hour, at 3:30, let's start right now with Pat Michaels.

MR. MICHAELS: If we could bring down the lights, I'd appreciate that. It's nice to be here. I feel like the vice president in the campaign of 1988, who said, I want my full 30 seconds to explain the Middle East. So, I'd like my full 15 minutes to explain global warming, which means the lights are going to have to come down even further, because no one can see the slides. Thank you.

Okay. Global warming, back in 1990, the United Nations did a silly thing. They got a group of as many scientists as they could find that they approved together, and decided to ask them what they could agree on to form a consensus. Anyone who has ever been to a faculty meeting knows what a foolhardy thing this is. But the United Nations in 1990 produced the report that served ultimately as background for the framework treaty on Climate Change Framework Convention, which, of course, why we're chatting so amiably today. It's what to do about this convention.

I thought I'd take you through where the science has evolved since the United Nations produced that report, and I will tell you at the outset that I am not surprised, and I've heard rumors that one of the big British science magazines is about to carry a large piece saying, the skeptics won. In other words, the people who said that it was not going to warm up nearly as much as the United Nations had said back in 1990, turned out to be correct.

This is the problem, this is the operative phrase from that entire 1990 United Nations' report, it says, "When the latest models of the atmosphere are run with present concentrations of greenhouse gases, their simulation of climate is generally realistic." In other words, the climate models in 1990 that were predicting an average of 4.2 degrees of warming for doubling carbon dioxide were generally realistic, i.e., right. Several scientists, not a small band of skeptics, but a very large and disconcerted group of people, thought this statement was wrong, because certainly the largest scale of climate is the planetary surface temperature. These models say that the planet surface temperature should have warmed between 1.3 and 2.3 degrees by 1990 as a result of human activity.

Here's how much it warmed. This is the northern hemisphere's temperature history from Jones and Wigley, we'll accept that everything that you're about to see in this talk is either a data set from the refereed literature or from the refereed literature. The warming was not 1.3 degrees, it was bout .6 degrees Celsius in the northern hemisphere over the last 100 years, but a large amount of the warming was before World War II, and Burt Bolin from the head of the IPCC is now on record as admitting that this warming has very little to do with the greenhouse effect, which leaves you about a maximum of about three-tenths of a degree of warming due to anthropogenic-generated activities.

Lesson number one about the greenhouse effect, you don't care whether it warms, you care how much it warms. If the warming is small, you really don't care. If the warming is large, you do. If it's primarily in the winter, you don't care very much. If it's primarily in the night, you don't care very much. If it's in the summer days, you care a lot more. So, it's not just whether it warms, it's how it warms.

Well, unfortunately, there are some problems with this record. For 1979 until now, we have satellites that have gone up, and you saw Roy Spencer's talk this morning. I will just remember that people who say that the science has settled on this issue are very unsettled by this graph. This is the global satellite temperature departure, which shows a statistically significant, I underline "statistically significant," net cooling of the global temperature. And it is a remarkable record when you compare it to what was predicted by the United Nations models back in 1990. The open circles are a very conservative estimate for the closed circles. It is what was supposed to have happened by 1990, and that is the northern hemisphere's temperature history through mid-1995 in this record, and you can see there is no change, of course.

Now, questions about the satellite have arisen, the satellite when and matches up perfectly with weather balloon measured temperatures between 5 and 30,000 feet, so that there is no doubt that all those thousands of people who have been sending up weather balloons have independently been in a conspiracy with Roy Spencer and his friends at NASA to lie, no doubt paid by the coal industry. Anyway, this really is a remarkable coincidence that they could produce this data by chance. In fact, 1 in 256,000 runs would still not get you such a correspondence.

Well, anyway the satellite data is really quite fascinating, because if we plot it out and look at where it's warming and where it's cooling, you see it's really not global warming, obviously. It's a warming of the mid- latitude land areas of the northern hemisphere. In fact, because there is a net statistically significant cooling of the whole record, it almost looks to me, as a scientist, like what's really going on here is the planet has remained in the slight cooling phase that it was in since World War II, but the greenhouse effect has done its best, and not a very good job, to try and superimpose some warming on it where you would expect to see it, which would be in the coldest air masses of the winter.

There are good physical reasons for that, by the way. I let the cat out of the bag a couple of minute ago. The greenhouse effect carbon dioxide changes have the greatest effect on temperature where the atmosphere is very dry at the surface, and that happens to be in the coldest air masses on the planet. So what you would really expect to see would be a warming of the coldest air masses, which would be here in Siberia and Northwestern North America, and not much else. And I'll show you some remarkable data on that in a second.

This is the satellite temperature record, by the way, but aerially weighted, or by latitude band, and you can see something quite striking. This is the zero line here. This is the temperature trend in degrees Celsius per decade. This isn't global warming at all. It's a warming of latitude band 25, 30, 35, 40, and 45 degrees north, and nothing else. The rest of it shows either negative or cooling.

Now, I made the statement that the warming is primarily -- what warming you see is primarily winter warming. Let's get away from the satellite records. The problem is, the satellite doesn't see absolutely down to the surface of the planet. The reason that I show you the correspondence between the satellite data and the 5 to 30,000 foot temperature is, when you get into the very cold air masses in the winter, the satellite doesn't see -- it just sees the top of the very cold air masses. It doesn't see the bottom of them.

What I'm going to do now is, I'm going to take the land surface record, the one that shows the warming, and subtract the temperature change in the summer from the temperature change in the winter around the globe so that you can see. The redder it is, the more the winter coldest temperatures have warmed up. This is quite remarkable. You see the one blob here in Siberia where the coldest, most obnoxious air mass that we know of originates, and its weaker cousin in Northwestern North America. So what you have here is not global warming really, what you have is a warming that is primarily a warming of the obnoxious air masses on the face of the planet where people live.

And, by the way, I have not read this one in the newspaper yet, but we have three measures of temperature. The satellite measured temperatures, the surface measured temperatures, and the balloon measured temperatures in the last decade, none of them, none of the only three records that we have show any warming. So what happened is that the coal industry must have bought all the guys that took the surface temperature in the last 10 years, too, I guess.

Anyway, after this carping by this small band of skeptics, the United Nations finally came around. And, in its new volume said, "When increases in greenhouses only are taken into account, most climate models produced a greater mean warming than has been observed to date, unless a lower climate sensitivity is used, there is growing evidence that increases in sulfate aerosols" -- these are particles that go out with the other emissions -- "are partially counteracting the warming."

The translation of this statement is very simple, either it's not going to warm up very much or something is hiding it. And, you can bet the sociology of science is that everybody is going to try very much to find something hiding the warming rather than having to write the letter to President Gore in the year 2001, Dear President Gore, we were sorry, we goofed, we overestimated the warming. Didn't know that much about it. Thanks for the frequent flyer miles. Hope you get your carbon tax. Yours truly, the consensus of scientists. P.S., sure has been good for research, hasn't it?

Well, anyway, this is a sulfate aerosol concept. You put these things in along with the greenhouse effect and it counters the warming. This is the paper that was, I think, the signal paper that pointed this out. It appeared on the Fourth of July last year by Ben Santer, et al. It ran from 1963 through 1987, and Bob Balling called me up on the Fourth of July when it came out and said, Michaels, have you seen this paper. I said, it's the Fourth of July, Bob, do you know how much illegal ordinance I have to blow up? This better be important. And I said, there's something wrong with those dates.

The fifth of July, I went to work and looked at the upper air data from 1958, when it starts, through 1995, when it stops, in the region where there is the most warming in this paper. Hold on to your hats, folks. This is the data from 1963 through 1987, and there is the rest of the data. You know, in debate it is often supposed to be a good idea to accuse your opponents of consorting with sheep, so that they have to say they don't. When this graphic got passed around in literature, all I heard was, not us. That's because the sulfate argument is really not a very good argument as it was based in this paper, at any rate.

This is the model that was used which has both warming from the greenhouse effect and cooling from sulfates. And you can see where it predicted it would cool are the regions of blue, and the satellite data, warming, warming, warming. Not a very good thing.

Well, anyway, I will then proceed to just hit two things, and I will be done, Ben. I would like to read you a little bit about the new United Nations report. This is one of my favorite sentences. It says, "Warmer temperatures will lead to prospects for more severe droughts and/or floods in some places and less severe droughts and/or floods in others." When I asked Tom Karl (?), who wrote that, what person wrote this, he said, a person didn't write it, it was written by a committee.

And so, I'd like to show you what the United Nations says will happen as a result of global warming. This is now diagram this sentence, "More intense wet periods, more intense dry periods, more intense wet and dry periods, less intense wet periods, less intense dry periods, and less intense wet and dry periods." So, in other words, whatever happens, unfortunately and this is the administration's strategy, whatever happens will be blamed upon global warming, including cold temperatures that happened in February of 1996.

Well, I'll finish with a little one-minute diatribe on how federal climatologists don't really tell you the truth, and how your government is trying to mislead you. Everybody saw the press release in January, that extreme rainfall has increased by 20 percent over the United States. This press release was timed to come out right during the California flood that was prepared a couple days after the news stories. In fact, Tom Karl at NCDC, National Climate Data Center, told me that.

Now, here is the data that went into that. What it was, was rainfall data from around the United States for storms that produced two inches or more in 24 hours. Now, I had never heard that a rainstorm of two inches in 24 hours is intense or extreme, but that's the level of rhetoric that's applied to this issue. If you ask the folks who wrote this paper if there is an increase in rainfall of storms of three inches or more in 24 hours, they will tell you, no. So it's rainstorms between two and three inches in 24 hours. By the way, everybody out there would like one of these right now. It would probably do wonders for Virginia agriculture. So I'm not so sure that at two inch rainstorm is all that bad in the summer.

Well, anyway, the percent of rain falling in the United States as a result of these storms has changed over the course of the century. It's changed 1-2 percent, not 20 percent. How did they get 20 percent? Well, you see, the average amount of rainfall that falls across the U.S. from storms of more than two inches is 10 percent. In other words, 10 percent of all rain comes from storms with two inches or more. It changed from 9 percent in 1910, to 11 percent by 1950, before the greenhouse effect had changed very much. They took the 2 percent, divided it by 10 percent, and said, that's 20 percent. Can we please have a carbon tax, we're wrecking the climate.

Now, suppose we had told the truth? The amount of rainfall coming from storms of less than two inches has declined, perhaps as a result of human activity, from 91 percent of all rain to 89 percent of all rain. That's how this issue gets exaggerated.

Thank you very much.


MR. WATTENBERG: I'm working under the general proposition, Pat, that your answer to the question, must we act now to avert a climate catastrophe is no.


MR. WATTENBERG: Right, okay.

For another perspective, Alan, why don't you go ahead. Thank you, we're right on time.

MR. ROBOCK: Thank you for inviting me here. I am a scientist. I'm a professor at the University of Maryland. I have a statement out there. I don't get any money from any interest group. I don't have -- I don't represent anybody except for myself. I'm part of the international scientific community. I participated in the IPCC report. So I'd just like to give you my perspective on what the science is and what we should do.

The IPCC conclusion for 1995 was that the balance of evidence suggests that there is a discernible human influence on global climate. So this is the balance of evidence, not unambiguous proof. And the report also points out that our ability to quantify the human influence is currently limited because there's so much natural variability still in the climate system. We're trying to find a small signal among normal, natural inter-annual climate changes, and because also, we're -- the models are not perfect. We're uncertain about exactly how the climate system works. And these uncertainties include the magnitude and patterns of long-term variability.

So, what is this balance of evidence? What is the evidence? Why do we think that we've seen a human impact on climate? First of all, it's gotten warmer. Pat spent a lot of time showing the last 20 years, but that's much too short a time scale to really look at for this problem. We have to look at a much longer time scale, because there are natural fluctuations in the climate system that can take place on inter-decadal time scales. There can be changes of ocean circulation. There can be energy which can go in and out of the oceans. And, in the North Atlantic Ocean, for example, scientists have identified 40 and 50 year oscillations in the ocean circulation that can also impose climate changes of about the same magnitude that we see. So, El Ninos can come and go, and some year can have more intense ones, which also have a large impact on climate.

Volcanic eruptions can cool the climate for a few years. The figure Pat showed for -- based on Ben Santer's work showed cooling after the data Ben used, and that's because there was the huge Mount Pinotuba volcanic eruption just after that. We understand that. That is what climate models predict, and that's what the climate system did. So, if we use the most recent climate models to include all the causes of climate change, greenhouse gases, aerosols, volcanic eruptions, ozone depletion, solar variations, El Nino, then they do a good job at reproducing the climate change of the past 100 years. And it would be -- and nobody has figured out how to explain the warming of the last 100 years without some other cause of climate change, most likely greenhouse warming.

But, even though the warming of the last 100 years is definitely a detectable climate change, that doesn't say what caused it. It could have been caused by something else. And so, you use a model, you put in all these different causes of climate change and see what comes out. And the most reasonable thing is that it was caused by greenhouse warming.

But you can't prove it to a statistical certainty because there's so much natural variability. There is a very small chance that natural variability could have caused this. The group at Princeton University NOAA Geophysical Fluid Dynamics Lab has tried to test this by doing a 1,000- year run with a climate model without any greenhouse gases changes, no volcanoes, no aerosols, no solar variations and use this as a model of the natural variability of the climate system, because we don't know what this system would have done without all these other inputs. We only have one Earth, we can't reproduce the experiment in the real world, so we use models. And, in their model, they never got such a large warming in the whole 1,000 years.

And, it's like a six significant -- six standard deviation difference. So it's statistically certain that this warming is not caused by natural variation, if their model is a good model of the climate system, and it includes the ocean.

What else do we see? The stratospheric temperatures have been decreasing. The Spencer and Christy data do a wonderful job of showing that in the last 20 years, with the exception of a few warming events after El Cajon (?) and Pinotuba volcanic eruptions. How do you explain this large cooling of the stratosphere? My own research shows that you don't get warming of the surface and cooling at the stratosphere at the same time in natural variations. The logical -- the most reasonable assumptions based on other climate models is, it's based on ozone depletion and increased greenhouse gases, increased carbon dioxide.

Sea level is rising, and it's been observed to be rising. Sea level isn't falling, sea level is rising. What causes that? Thermal heating of the ocean and melting of glaciers on land. Although, the latest models show that in the future, Greenland will probably melt more than increase it's snow, but Antarctica, as the climate warms, there will more snow, but there won't be much melting. And so they sort of balance out. And on these two major ice sheets, there won't be much of an impact on sea level rise. But still, glaciers on land will melt, and the ocean itself will warm up and get thicker.

So, and glaciers are melting. All around the world the last couple hundred years, the glaciers are melting. Another thing is that surprises are possible. We're talking about gradual smooth climate change which the models get. What if there's a surprise? What if something that nobody understood and nobody predicted happens?

The ozone hole is a good example of that. Rowland and Molina predicted that Freons would cause ozone depletion in 1974 in their famous paper, and they got the Nobel Prize in chemistry two years ago. But they weren't smart enough to predict the ozone hole, nobody predicted it. Nobody predicted that all of a sudden all the ozone over Antarctica would disappear for a month in October and spring in the southern hemisphere. And now, we've figured out what causes this. It's caused by heterogeneous chemical reactions. That means, the Freons are reacting on polar stratospheric clouds which weren't even well observed before. Now, we've figured it out after the fact. But nobody predicted it ahead of time.

What might the climate system do that we aren't clever enough to figure out? Wally Broecker has suggested in the past there have been rapid shifts of ocean circulation where the gulf stream doesn't head toward England but heads in a different direction, and you can get this rapid overturn of the ocean. Are we warming climate to a level above which some unknown, some threshold, where all of a sudden there's going to be a rapid change? Nobody knows, but it's possible.

What would be the impacts of this warming that's predicted by climate systems? Well, I won't go into much detail about that. I agree with Pat, there is not much evidence currently that big storms, or droughts or floods are caused by climate change now. They're part of the natural variability of the climate system. They've happened in the past. They'll happen in the future.

Precipitation has been increasing in the mid- latitudes over the last 100 years, as Pat showed some data from. So where is this mid-latitude drought that's predicted? Well, it hasn't warmed up enough. But, models show that in the future the atmosphere will be warm enough, it will hold more water and that will compensate the increased precipitation and the net result would be drought.

So there's a possibility of more violent storms, forest declines, pest outbreaks, winter skiing and snowboarding won't be as good, increased human mortality from heat, a lot of possible, but unproven consequences. So what should we do? Policy -- now, I'm an expert in meteorology, I'm a climate scientist. So this is more my opinion, based on my scientific knowledge and my political knowledge, the second of which is not as good as my first one. And Fred Smith said this morning, logic is for losers. So I can't help but think that way, so I'm not going to stop now.

The basic question we have to address is would slower climate change be better for humans than rapid climate change, because climate's going to change. It's going to warm no matter what we do. All the greenhouse gases we've put in over the past -- our lifetimes are still there, most of them. And so it takes a long time, and they'll be there for a long time. And the climate system is slow to respond. So all the greenhouse gases which are there now will warm the climate in the future, no matter what we do, even if we stop putting them in now. So there's a long time lag in the system. So it's going to warm anyway.

The most we can hope to do, I think, is to sort of slow it down a little bit. So would slower climate change be better than rapid change? Do we have to act now or can we wait for a while and let it change for a while and then can we act in the future, when we have better understanding of the science and also better technology to deal with the mitigation. And is there some threshold that we must avoid that would result in a vastly greater harm to society? If we let it go along will we -- at some point the danger be much larger. Those are the questions that we have to answer in order to decide what to do. And the problem is, we don't know the answers to these questions. And I don't think we will for a while.

Must we act now, or will continued change be okay? I don't know. Is there some threshold? I don't know, possibly. Would slower climate change be better than rapid change? The changes predicted is going to be -- let's take the IPCC figure, two degrees Celsius by 2100. At the last great ice age the -- when there were mile thick ice sheets covering North America, the global climate was only about five degrees Celsius colder than it is now. So we're predicting that it will go half the way in the other direction, to a temperature warmer than ever before experienced by not only anybody on the planet, but any members of our species, in the past couple-million years. And it will be at a rate faster than climates ever changed before.

So the question is, will this rapid climate change -- will we be able to adapt to it, or will it be harmful, or should we try and slow it down? If we don't know, I think in the -- because of caution we should act as if the answer is yes. What should our -- if we wait until we've detected a climate change for sure, we can't go back and take all the greenhouse gases out of the atmosphere. So prudence dictates that we shouldn't do this uncontrolled experiment, an environment impact statement written on putting greenhouse gases in the atmosphere would never have passed muster. But, we're doing it inadvertently. We're doing it because we want to do other things. We want to heat out houses and cook. We're not doing it because we want to pollute the planet.

What should the response be? What do I think? I think it should be three things. It should be adaptation. It should be improved knowledge and it should be mitigation. Adaptation means that no matter what happens the planet will warm and we have to deal with it. And one way to deal with it is to do more studies of how it will change, what will the patterns be, so that we can adapt in a better way and plan for it. Because we don't understand the climate system well enough, we need better data, better models, better computers, more trained scientists and engineers, to address the problem. This would be a good investment for society. Right now the U.S. Global Change Research Program has $1.8 billion, $1.1 billion is for hardware, for satellites, mainly for NASA, and about 700 million is in research funding. That's barely adequate to answer all these pressing questions.

With mitigation, that's what most people focused on today, should the U.S. actually put a carbon tax on or reduce carbon dioxide emissions? Well, again, this is really an opinion. Some people say, that well, we should wait until we understand, until we know better what to do. The problem is, people will always make that argument. Ten years from now people will make exactly the same argument. Well, we don't know everything, let's wait, let's wait, and we'll have better technology in the future. That's always the case.

I think we should start now to try and figure out how to deal with it and start doing some research on it. Let's try some small things first that can help. If we don't begin, we'll never get to that point. And I think it's actually an opportunity for American industry to develop the energy efficient technology that will be needed, not only by us, but by the whole world.

The real problem, as has been pointed out already, is China and India, with these huge populations. They all want to have a refrigerator and a car and live like us. If they used the same technology we use, they'll put tremendous amounts of CO2 in the atmosphere, much more than we will. So I think any action by the U.S. and the other developed countries should be as an example to the world. If we don't do anything, nobody will ever do anything. If we do something, as we have in many other issues, set the standards for the world, in environment protection, in morality and how to treat people, and democracy, other countries follow. So as an example to the world, we can begin slowly to take actions that will be good for us and for the rest of the planet in the long run.