Examination of Witnesses (Questions 140-150)|
Professor Richard Lindzen
25 JANUARY 2005
Q140Lord Kingsdown: Not to mention global warming?
Professor Lindzen: Right. If you go to the chapter
on physical process and climate feedbacks, you do not find disagreement,
that we do not know how to do water vapour, we are uncertain about
the positive feedback. When you get to clouds, you get open admission
that they are completely uncertain and a fundamental weakness
in the predictions, and it is understood, but we were not permitted
to say it, that these are fundamental to the predictions of large
warming. That was a little bit peculiar. You do not find the disagreement
that John is talking about. The only place you begin to see anything
is in the Summary for Policymakers. This has been a characteristic
of these documents from the beginning, as far as the press goes,
as far as politicians go, they see the first two lines and maybe
the first paragraph and that is it. Typically, in the Second Assessment,
the line which carried the day was a discernible human impact
on climate. That was the smoking gun for Kyoto. Discernible suggests
it was less than the total, and that the total is about one-sixth
of what the models predict does not seem very alarming to me,
but it was enough to get people riled up.
Q141Lord Lawson of Blaby: Lastly, can I refer
to one particular part of his evidence, which is exactly the answer
which Lord Lamont quoted, the very first part of his answer. He
went on to say: "It"that is the average global
temperature"has been a steadily rising trend during
the 20th century." Then he says that for the first half of
the century it was nothing to do with greenhouse gases because
there were not greenhouse gases, it must have been something non-anthropogenic.
Then he contradicts himself somewhat by saying that there was
no temperature rise between 1950 and 1970, and then he says, and
I quote: "From 1970 to the present time there has been a
very steady increase in water vapour. The rate of increase is
larger than it has been for a very long time, probably for 10,000
years. The total increase during the 20th century is quite out
of scale with any variations known to us."
Professor Lindzen: He said that about water
Q142Lord Lawson of Blaby: Yes. This is an uncorrected
transcript but I assume it is likely to be right. That, it seems
to me, is the basis of his alarmist projections. What is your
response to that?
Professor Lindzen: Astonishment. The temperature
change over the past century, as you pointed out, is irregular.
It went up rather sharply from 1920 to 1940. There is even, between
1919 and 1921, a period where you had a half degree in one year,
or two years. Between 1950 and the 1970s you had cooling, and
Crispin Tickell even wrote a book about how society must respond
to the coming ice age. Then you had warming and, as far as I can
tell, on the surface record, you have rapid warming between '76
and about '85, and then you have fluctuations about it. I remember,
when the first satellite data came out and there was only 20 years
of it, they said, "Well, you can't make a trend from 20 years'
data." All of a sudden people see a peak and they say "That's
a trend." There is no steady increase through the 20th century,
there is a net increase, and it is a few tenths.
Q143Lord Kingsdown: You have already mentioned
water vapour once or twice this afternoon, but I understand your
position is you regard this as having probably a negative feedback
effect, that is, that it calms warming down, whereas the scientific
consensus, as we understand it, is that it has a positive feedback,
that is, that it makes things worse?
Professor Lindzen: The IPCC chapter is agnostic.
The models say it gets worse. The modellers acknowledge they do
not have the physics appropriate to water vapour. That is the
situation as it is now. In 1990 I wrote a paper in which I said
global warming scenarios depend on this water vapour feedback;
without it you do not get much and we do not know much about it,
and they said "Can you imagine any way that would be negative?"
I said, "Sure." It turns out, if you have a warmer world
and clouds go higher, they detrain, let us say, they merge with
the environment where it is colder and you have lower humidity
and that could end up reducing water vapour. That has actually
been confirmed by studies since then. In the meantime, we wrote
a paper in '93 examining this and found that the physics of water
vapour in the tropics was different from that. That would work
near the top, but, in fact, the source of water vapour in the
tropics was rainfall evaporating into the environment, in large
measure. We pointed out that the amount raining into environment
depended upon how much did or did not rain in these tall, cumulus
towers. It is well-known that, when the temperature increases,
more rains in the towers and less is available to the environment,
so there still could be a negative feedback. Subsequently, we
realised that change in the humidity of a region in a sort of
continuous way is rather difficult, even by this mechanism, but
what you saw was a short boundary between dry and moist regions,
cloudy and clear regions, and the change in area could really
be a more significant feedback. We have been working on that since
and it looks very much like a negative feedback that would be
large enough to swamp any of the positive feedbacks in the model.
It is a research area, but it is politically incorrect these days
to speak of the world, or the earth, as in some sense being engineered.
If any of you have a background in engineering, I do not know,
you never build anything with positive feedbacks unless you want
to amplify something. You build everything so that the feedbacks
hold it in place. The whole notion, I grant you, this is metaphysical,
that the earth is a system on the border of instability that is
kept from running away only by the gentle ministrations of bureaucrats;
it seems to me, strange.
Q144Lord Kingsdown: Can I just go on to ask
you how far your view of the role of water vapour is shared by
Professor Lindzen: That is shared universally.
All of them agree, no model gets a lot of response to CO2, much
more than you would expect on basic physics, unless water vapour
and cloud kick in to make the system much more sensitive than
it would be in the basic physics. That is true and accepted.
Q145Lord Sheppard of Didgemere: Can we move
on to the Kyoto Protocol. Your evidence implies that you consider
it would have little or no effect on the rates of future warming.
Is this because reductions targets are too low, is it that we
are doing too much or not doing enough, or what?
Professor Lindzen: In a sense, that is right.
What you have with carbon dioxide is, first of all, as I said,
you are already three-quarters to a doubling and quadrupling,
just do it again. No matter what you do at present, unless you
change the amount of these things in the atmosphere it is not
going to change the forcing of climate. Kyoto, for instance, is
changing the emissions but it is not eliminating the emissions,
so you are still adding to the atmosphere and you can calculate
the impact. It is less than a tenth of a degree by 2100, or something
like that; it would be unmeasurable. The question is then, as
you say, maybe it is not enough. What would be enough to impact
the level of CO2 to get us down from the horrible point we are
at now? I should mention, I find this a little bit mind-blowing.
If Sir John says one degree will cause all sorts of havoc, we
have already had 0.6 and we have seen a world of increased prosperity,
we have seen a world of greater food production, we have seen
all these things. I do not see the evidence of a horror story
there. In any event, getting back to what you are asking, to cut
down the CO2 itself would require not a few per cent below 1990
but probably in the order of 60 per cent below 1990. As far as
I know, no-one knows how to do that. Even the IPCC, I should mention,
in their Section 3, pretty much concludes we are not going to,
even if you believe the models, even if you believe everything
about it, they are not going to stop it. The primary concern is
can we adapt, and the obvious answer has been that you need the
resources to adapt.
Q146Lord Sheldon: How do you see the work of
the IPCC? Do they take full and proper account of all views, however
different they may be, or are they all equally represented?
Professor Lindzen: I think it is a very distorting
process. As I have said, it has many stages, so you have the writing
of the scientific text, or the substantive text; that is done
by the lead authors with the co-ordinating lead author, and what
I used to refer to as political correctness monitors, people who
go around to the co-ordinating lead author, who is chosen by the
executive, whereas lead authors are chosen by the Technical Unit
at the Hadley Centre, Working Group One. The co-ordinating lead
author has to make sure that it does not say anything that would
be too far in one direction, not the other, but that is okay.
At the end of the day, when I look at the Working Group One Report,
I would not use it as a textbook, I would not find it all that
helpful, but also I do not find it says anything terrible. It
is very much on the level of saying "We don't know. There's
uncertainty." I give an example in my testimony of how the
Working Group describes what appears later in the Summary and
it is like day and night. That is the problem. This came up recently.
There was a kind of scandal. There was one group looking at the
impacts of global warming and they had a guy called Chris Landsea.
Chris Landsea is probably the leading expert on the statistics
and history of hurricanes and he has written a lot of papers pointing
out there is no obvious relation that can be discerned between
hurricanes and temperature of the earth and no evidence that warming
would increase hurricanes. On the same chapter committee was a
lead author, Kevin Trenberth, and Kevin participated in one of
these dog and pony environmental shows, in which he said "The
hurricane season this year in Florida is a warning about global
warming." That is ambiguous. Is it due to warming, or is
it an example: who knows? Landsea said, "How could you say
that when the evidence says there's no connection?" What
Landsea realised, I think, was no matter what the chapter ended
up saying, even if it said "There's no relation," it
would be represented by Kevin, or John Houghton, or whoever, and
it would be said that there is a connection. This has been the
problem. You have this damn Summary for Policymakers, which ends
up saying things that are rather different. They have a funny
way of using language. For instance, apparently, maybe it has
changed, the last time, but for the first two IPCCs there was
an agreement that the Summary for Policymakers, which is not written
by the scientists, it is written in a plenary session with NGOs
and government officials, and so on, if it says something that
is not in a chapter, the chapter can be modified. The way it is
modified is interesting, at least what I have seen is. There will
be a line thrown into the chapter that corresponds to the Summary.
It is not that they pull out much of the rest but there is a sudden
cognitive dissonance in the thing, and so their statement that
the Summary is consistent with the text means that what is in
the Summary can be found somewhere in the text. They do not go
on to say that sometimes the opposite is also found in the text.
I do not know. I have this statement at the end that when language
becomes foolish our ideas follow suit, and the reverse can happen.
I think we are seeing that within IPCC.
Q147Chairman: Listening to a great deal of your
evidence, and maybe we are just coming to the end and I would
like to thank you very much for what you have said, there is one
question that comes immediately to my mind. If it is like you
present it, why are governments spending this enormous amount
of money producing all this stuff, because there are enough of
us sitting round this table who have spent our lives trying to
control government expenditure in our previous incarnations and
there are plenty of arguments for not spending it. If it is anything
like you say, why are they spending all this money?
Professor Lindzen: I will give you a semi-serious
answer, because I do not know the answer. My semi-serious answer
is that I have realised, over the last 20 years and in dealing
with public officials and ordinary people, that the last thing
in the world they want to do is dig into science, to deal with
mathematics, read this. If they can avoid that by spending a trillion
dollars, they will do it.
Q148Lord Sheldon: I know you cannot give an
answer to this question, but can you make a bit of a guess: how
much do you think is being spent on this, the whole of this business,
just a general figure?
Professor Lindzen: I think at least 25 billion,
30 billion at the research end, but then there is probably a smaller
but not insignificant amount surrounding. By now I figure that
well over 10,000 diplomats and bureaucrats are working on negotiating
the various things and analysing them and working out the economics,
and so on, so it is a growth industry, but I do not think it is
Q149Lord Macdonald of Tradeston: If I can go
back to the question of the observed 0.5 per cent against the
modelled 3 per cent increase.
Professor Lindzen: Well, 3 degrees versus a
Q150Lord Macdonald of Tradeston: Thank you.
Three degrees; perhaps also the unknown factor that would have
to be found. There was a science programme on our television here
recently on global dimming, on "Horizon", which said
the fact that these particulates have been multiplying has led
to global dimming, this was all revealed to us after 9/11. Could
this be the unknown factor?
Professor Lindzen: It is an interesting thing.
One of the claims, and I discussed this in the deposition, is
that the models can simulate the past century and simulation is
a very low-order activity when you have adjustable parameters.
These aerosols you are talking about were a godsend to the models.
The reason they were a godsend is two-fold. Even if you know the
amount of aerosol you have in the air, calculating the thermal
forcing leaves you with an uncertainty of about a factor of six
to 10, because we do not know their properties very well. In addition,
we have no records of sulfate emissions before 1964, so to match
records before then you can devise ways of estimating how much
you have. Between estimating how much you have produced, and some
of these estimates are very weird, they have maximum production
in the depression and minimum during wars, it is hard to figure,
and the fact that you cannot calculate the radiative properties,
it is completely disposable. There is even a name for it in the
literature. The aerosol people say their ignorance is so big that
it might be legitimate to plug aerosols into the models and tune
the properties to make the models more nearly coincident with
the data. That is called the inverse method. They do warn, in
an article that I cite here, in Science magazine, that
then to use those properties to test the models is circular, and
Chairman: Thank you very much indeed. Really we are
very grateful to you for coming and for answering our questions.
Thank you very much.