[url=http://www.aph.gov.au/hansard/senate/commttee/S13568.pdf]EC100[/url][url=http://www.aph.gov.au/hansard/senate/commttee/S13568.pdf][/url]
Monday 21 February 2011 Senate EC 101
ENVIRONMENT AND COMMUNICATIONS
CHAIR—Dr Ayers we are all waiting with great anticipation to hear your statement in relation to Cardinal
Pell. Would you like to make that statement now?
Dr Ayers—The issue from my point of view and why I sought leave to respond is that the cardinal has in
terms of the letter we incorporated in Hansard made a number of propositions about aspects of climate
science that I have feel should not remain unanswered on the public record in this place. I would have been
happy to have responded directly to the cardinal but he has not approached me and I am not aware that he has
spoken with any others in the climate science community. I thought it was important to respond.
The difficulty with the assertions made in the cardinal’s letter is that they are based not upon contention in
the climate science field but on a book written by Professor Plimer entitled Heaven and Earth—Global
Warming: The Missing Science. The contents of the book are simply not scientific. I am concerned that the
cardinal has been misled by the contents of this book and I do not think it should stand on the public record for
that reason.
Why would I say this book is not science? It is not me who says it so much although I have read it myself;
it has been widely reviewed by people in the scientific arena and it has been very heavily criticised for not
presenting science but presenting a polemic from one individual. It has not been scientifically peer reviewed. I
would like to step you through each of the assertions in Cardinal Pell’s letter. The cardinal I do not anticipate
would be an expert in these fields of science so he has quoted very heavily from this book and the book is
frankly misleading to all Australians in terms of what it represents. I will read you once scientific review to
give you a sense of what one scientist from the University of New South Wales said about the book. He said:
Plimer has done an enormous disservice to science and the dedicated scientists who are trying to understand climate and
the influence of humans by publishing this book. It is not “merely” atmospheric scientists that would have to be wrong
for Plimer to be right. It would require a rewriting of biology geology physics oceanography astronomy and statistics.
Plimer’s book deserves to languish on the shelves along with similar pseudo-science such as the writings of Immanuel
Velikovsky and Erich von Daniken.
That is from Professor Michael Ashley from the University of New South Wales. That is very strong I am sure
you will agree. I have read the book myself and it contains phrases that had nothing to do with science. There
is a somewhat gratuitous attack on Chancellor Angela Merkel on page 441 the same page essentially that
contains a gratuitous attack on Minister Wong. Page 470—
Senator IAN MACDONALD—That does not make the book—
Dr Ayers—No the point is Senator that it is not science. The book says that it is Global Warming: The
Missing Science. Were it science that would be fine. To quote Professor Ashley again:
The book is largely a collection of contrarian ideas and conspiracy theories that are rife in the blogosphere. The writing is
rambling and repetitive; the arguments flawed and illogical.
Senator IAN MACDONALD—But Dr Ayers—
CHAIR—Senator Macdonald Dr Ayers is making a statement. You can ask questions after he makes the
statement.
Senator IAN MACDONALD—We are on limited time. It is additional estimates. In Cardinal Pell’s case
he did a written response which we tabled. I wonder whether it might not be more appropriate for Dr Ayers to
do a written response which can be tabled. I can assure Dr Ayers that I will be making sure his comments are
passed on not only to Cardinal Pell but also to Professor Plimer who says these same sorts of things about the
people you are quoting.
CHAIR—Senator Macdonald I do not want you to enter into the argument. I know where you are coming
from. My position—and our rule—is that Dr Ayers can put his statement on Hansard. He does not need to
write it; he is prepared to put it on Hansard now and it is on Hansard.
Senator IAN MACDONALD—You said that we have a limited time. How long is the statement likely to
be?
CHAIR—I am prepared to have it put on—
Senator IAN MACDONALD—The rest of us want to ask questions.
CHAIR—Senator Macdonald you have had plenty of time to ask questions. You are the one wasting my
time now. I think that you should let Dr Ayers go on. Dr Ayers how long do you think the statement might
take?
Senator BOSWELL—Mr Chairman I am very happy for Professor Ayers to make the statement but I do
think we should give the same opportunity to Dr Plimer. You have got every right to criticise him but I think
he has a right to defend himself in the same forum. So if you are going to—
CHAIR—I do not know whether it is appropriate for Dr Plimer to be before estimates.
Senator BOSWELL—It is just as appropriate—
CHAIR—Dr Ayers how long do you think it will take?
Dr Ayers—It would probably take between five and 10 minutes.
CHAIR—I think that we should continue.
Senator IAN MACDONALD—Being aware that I will send it to Dr Plimer and ask him to write a written
response to incorporate.
CHAIR—Very good.
Dr Ayers—Just responding to Senator Macdonald I will be making contact directly with the cardinal after
these estimates. As I said at the outset from my point of view I am disappointed that I was not having this
discussion with him directly. I am very happy to do that.
Senator IAN MACDONALD—His letter is dated July—that was seven months ago.
CHAIR—Dr Ayers I would ask you not to engage directly with Senator Macdonald. That will lead us
down a blind alley I can assure you. I am saying that you should make your statement and then Senator
Macdonald can ask you questions.
Dr Ayers—Chair my proposition here is that there are about half a dozen assertions in the letter and I
would like to respond to each one if I may. First of all I should just say that a critique of Professor Plimer’s
book is available. There is another university professor named Ian Enting at the University of Melbourne and
if you put ‘Enting’ and ‘Plimer’ into a search engine you will come up with a 55-page document detailing
mistakes misunderstandings and misrepresentations. That is available and I will be sending that to the
cardinal. Everybody who wants to dig into an analysis of the book can do that.
On the first thing the Roman warming Professor Plimer asserts that the temperatures during that period
were two degrees to six degrees warmer than today. If you go through the book there is not a single scientific
reference in the book that makes that statement. It is an assertion without any scientific evidence. The example
of a book by Lamb published in 2007 is about as close as you get. The strongest statement in that says:
By late Roman times particularly the fourth century AD it may well have been warmer than now—
Now being the mid-1970s when the book was written. In fact we know the earth was a little warmer. So there
is no cogent evidence being provided at all for that statement. I have no idea—
Senator IAN MACDONALD—East Anglia University—
Dr Ayers—I have no idea where the two degrees to six degrees comes from. I will heed the chair’s advice.
What is interesting about that is that there were things like assertions that grapes were grown in England and
that the two degrees to six degrees would support that. Grapes are grown in England today. There are more
than 400 vineyards. That sort of level evidence is not science; it is anecdote. If Professor Plimer has time he
should publish it in a scientific journal and then we can have it level. That is that: there just is not any evidence
in the book.
If we move on to the medieval warm period he references a study of 6000 bore holes. These are holes in
rock where the temperature diffuses down and with a mathematical technique called inversion you can
reconstruct what the past temperatures would have been based on thermal diffusion. The reference appears to
come from an article by Professor Wally Broecker a renowned oceanographer written in 2001. Professor
Plimer does not quote Professor Broecker’s conclusion which is:
The case for a global medieval warming period admittedly remains inconclusive.
So that does not support it. What Professor Plimer then does is take one of the references from this book and
refers to a 1997 paper by an author list led by someone named Wang. What is interesting about that is that the
same authors in 2008 published a subsequent paper which says in fact that you cannot use their first paper for
the purpose. They say:
The results of our earlier paper cannot be used for comparing the medieval warm period to warmth in the 20th century.
Which is exactly what Professor Plimer does. This paper was available in 2008 a year before he published his
book. He has used a paper that the authors themselves say cannot be used in a particular way. That is not
science.
A second thing to do with the medieval warm period is on page 66 where he says:
Bore holes give accurate temperature histories for a thousand years into the past … Northern Hemisphere bore hole data
shows the medieval warm period and the cooling of 2 degrees from the end of the Little Ice Age.
When you go and look at the scientific paper—which you assume is about bore holes Northern Hemisphere
medieval warm period—you discover the paper is actually not about bore holes but about an ice core; it is not
taken in the Northern Hemisphere it is from the Antarctic; and it is for the period 10000 years to 20000 years
ago not the Roman warm period. That level of getting references wrong is not science. So the book does not
provide evidence about the medieval warm period or the Roman warm period.
The cardinal in his letter says that he has metadata analysis—that is an analysis that sits above all the
papers that are random reviews—but he just cannot find it. That’s okay. If he can find it I would be happy to
look at it. I know of three metadata analyses though. One of them is in the Intergovernmental Panel on
Climate Change Working Group I report from the Fourth Assessment Report. It answers all these questions.
However there are those who feel that the IPCC is somehow biased so they would not use it.
At the time it was being written in 2006 the US National Academy of Science carried out an independent
review and wrote a report entitled Surface temperature reconstructions for the last 2000 years because there
were those who said the IPCC process was not robust. So we have an independent report from the National
Academy of Science. Their conclusion is:
• It can be said with a high level of confidence that global mean surface temperature was higher during the last few
decades of the 20th century than during any comparable period during the preceding four centuries.
They go on to say:
• Less confidence can be placed in large-scale surface temperature reconstructions for the period from A.D. 900 to 1600.
The medieval warm period is in there.
Presently available proxy evidence indicates that temperatures at many but not all individual locations were higher
during the past 25 years than during any period of comparable length since A.D. 900.
The Roman warm period was 250 BC to 450 AD. So they do not support it. That is two metadata analyses.
They were both available to Professor Plimer. They are not mentioned in the book. So it is not a fair review of
the scientific literature. The final point I will make is that the US EPA in December 2009 published the
administrator’s results on the ‘endangerment’ and ‘cause or contribute’ findings for greenhouse gases under
section 202(a) of the Clean Air Act. This was a process in which the Administrator of the EPA made a finding
that the current and projected concentrations of six well-mixed greenhouse gases in the atmosphere threatened
the public health and welfare of current and future generations. I will not go into the ‘cause or contribute’
finding but the point was that there was a profoundly careful review. They had a 60-day consultation period
for public comment and 380000 public comments were taken in. They all included the statements made in
Professor Plimer’s book that have unfortunately misled Cardinal Pell. Not one of them was supported. So there
are three metadata reviews—from the IPCC from the National Academy of Sciences and from the US EPA—
that do not support the propositions that are being put.
I will move on to carbon dioxide where Professor Plimer has brought to the attention of anybody who reads
the book—and Cardinal Pell has picked it up—that 90000 measurements of CO2 were done over the last 150
years by a particular method. He contrasted those with the carbon dioxide record from Mauna Loa in Hawaii
which from the fifties has documented the increase in human activities. It looks as though that is a fair
comparison but it is not. It is actually verging on disingenuous. The fact is there are 150 stations measuring
CO2 worldwide 110 of which meet the standards such that the annual analysis done by the World
Meteorological Organisation’s World Data Centre for Greenhouse Gases uses those to describe CO2
everywhere. You simply cannot if you pay attention to all the data available reach the conclusion that CO2
levels were higher in any other period in time.
Professor Plimer does not mention that in 1986 all the old data that were collected over the last 150 years
were reviewed in a paper by Fraser et al. I can give you the citation if you like. The issue here is that in
Australia we have at Cape Grim in Tasmania one of those 110 high-quality baseline stations measuring CO2.
If you look at that and if you look at the work done in the Antarctic Division on ice cores and firn which is the
loose layers of snow that compact down at about 80 metres—air has been extracted all the way down from the
present down into the past through the firn layer and into the ice cores back 2000 years—there is absolutely
no possibility that the global CO2 levels were 400 parts per million last century. It is just implausible. Yet on
the basis of 90000 measurements from a paper by a fellow named Beck that is the conclusion put in the book
and that is the conclusion picked up by Cardinal Pell.
Professor Plimer also did not cite the fact that during the year after the Beck paper came out there were
two rebuttals published in the same journal pointing out the errors in it. They were not referred to. So there is
very selective use of data the whole way along. The Australian scientists who have worked on the carbon cycle
include those working in Canberra at one of the two international offices of the Global Carbon Project where
on an annual basis CO2 levels are reviewed the carbon cycle is reviewed and the budget of carbon going into
the atmosphere the oceans and the land surface is all reviewed and published. It is not in this book because if
it were in the book the conclusions that are in the book could not be reached.
So what I am going to suggest to Cardinal Pell in due course is that he comes with me and visits a range of
climate change science establishments in Australia and has a look at the science directly not through this book
but through the lens of what men and women in Australia are doing in scientific institutions that is valid that
is published and that has real credibility. My contention is that Cardinal Pell may well become an ambassador
for the quality of climate change science if he is exposed to the quality of the science that is done. That is my
aspiration. He can make his own decision about whether the science says what Professor Plimer says but I
think he will become an ambassador for the quality of the science we do in this country. It is absolutely not
honoured by this book.
I know these are strong statements but I am the head of a national agency and the information that is out
there is not adequate based on what I know. So I am taking my job seriously and making a strong statement.
There are some other things in Cardinal Pell’s letter that I will not go into because I can see people’s eyes will
start to glaze over. I will just make two other comments. At one stage he lists greenhouse gases. Included in
the list is the gas nitrogen. That is not a greenhouse gas; it is 78 per cent of the atmosphere. You cannot have
people out there telling the public that nitrogen is a greenhouse gas because it is not.
The final point I will make is on the statement from Professor Plimer that CO2 from fossil fuels accounts
for 0.1 per cent of the greenhouse effect. There is a parameter called climate sensitivity. It is the temperature
increase you would get if you doubled CO2. The conventional view which is very well attested to in scientific
literature is that it is about two or three degrees. That is roughly it. At equilibrium when everything comes
into balance that is what the temperature of the Earth would go up by. Professor Plimer says that is not right;
he says it is only half a degree. At least he says that in one part of his book. In another part he says that it is
1½ degrees. So he is not consistent with himself. You can do a very simple calculation. Professor Enting—the
guy who has done the 55 pages collecting problems with Professor Plimer’s book—shows you how to do the
calculation. You can compute the change from 280 parts per million pre the industrial age to 385 now. Using
Professor Plimer’s climate sensitivity it would increase temperature by 0.23 degrees. We have seen about 0.7
but he has put his sensitivity below that. If 0.23 degrees is only 1.1 per cent or one thousandth of the
greenhouse effect it implies that the greenhouse effect is 223 degrees and without it our planet would be as
cold as the outer planets. So the calculations in this book are just erroneous. I will give up at this stage. There
is plenty more I could go on with but I will not.
CHAIR—Dr Ayers thanks for taking the time to take us through those issues. So you are going to convert
the cardinal and make him a missionary for climate change?
Dr Ayers—No. In fact I think that—
Senator Ian Macdonald—Who suggested to you that you might read this out tonight Dr Ayers?
Dr Ayers—Nobody. As I said I felt that it needed to be in the Hansard.
Senator Ian Macdonald—Yes I am quite sure it should have been but a written response would have been
equally as good because unfortunately Professor Plimer should he choose to respond can only put in a written
response. He cannot make the commentary that you have made.
Dr Ayers—I am happy for Professor Plimer to write to me.
Senator Ian Macdonald—No it needs to be done here. This is the trouble. The chair has allowed this to
happen. This is going to go on forever now.
Senator SIEWERT—You were allowed table that letter last time.
Senator Ian Macdonald—But that is tabling. I agree with that. He should have been able to table a reply. I
agree with that. Professor Plimer will not be able to come and talk to the committee.
Senator LUDLAM—He can publish another work of science fiction
CHAIR—Order! I am not going to have a debate taking place across the chair. If you want to ask any
questions of Dr Ayers on what he has just said I think it is perfectly appropriate to ask them now. Senator
Macdonald I invite you to ask any questions you have of Dr Ayers on what he has just put.
Senator Ian Macdonald—It is now 10 to nine. We have two hours left to do the whole of the rest of the
program. I would not impose upon my colleagues by asking any more. I have had my fair share. I just think
that it was an inappropriate decision of the committee to allow 20 minutes to be taken up by what is clearly an
interscientific argument.
CHAIR—It is about the best 20 minutes I have heard at estimates for a long time. Congratulations Dr
Ayers.
Senator IAN MACDONALD—You should go and listen to Professor Carter some day.
CHAIR—Before we move on I take it then Dr Ayers that you do not agree with the second paragraph of
the letter from the Cardinal to Senator Macdonald that says:
I am not surprised that the Bureau has acknowledged the veracity of most of the factual statements set out in my article
but I am pleased that it has done so.
You do not agree with that obviously.
Dr Ayers—No.
