Letters from UK Government’s Chief Scientific Advisor reveal critical view of Lord Lawson's climate arguments
- 27 Mar 2011, 00:00
- The Carbon Brief
Scientific Advisor Sir John Beddington
On the 31st March 2010, the House of Commons Science and
Technology Committee heard evidence for an enquiry into the
University of East Anglia's Climatic Research Unit's E-mails.
Present to give evidence were Lord Nigel Lawson, founder of climate
sceptic think-tank the Global Warming Policy Foundation, and Sir
John Beddington, the government's Chief Scientific Advisor.
In the same month, Lord Lawson asked John Beddington to review his
bestselling book about climate change: '
An Appeal to Reason, A Cool Look at Global Warming'. Beddington
obliged, sparking an exchange of official letters between the two
over the coming months - released to Spinwatch under freedom of
information legislation and seen by Carbon Brief.
The tone of the letters is polite, and Beddington's criticisms are
restricted to the scientific statements Lord Lawson makes in his
On some issues - the importance of improved water management for
example, he makes clear his agreement with Lord Lawson. However,
his assessment of the material in the book which discusses climate
science raises serious questions about the validity of the
arguments Lawson makes, and his interpretation of scientific
The full letters cover twenty separate points. To pick one
example of the material covered - when addressing the argument
often repeated by Lord Lawson (and more recently by the GWPF - for
here) that "There has been no global warming since the turn of
the century", Beddington writes:
"…short-term temperature trends are
meaningless in the context of global warming… In order to see the
effects of greenhouse gases, it is necessary to examine the
long-term trend, which has clearly been upward (global average
temperatures are now about 0.75°C warmer than they were 100 years
ago, and the last decade has been the hottest since records
In his letter in May 2010, Lord Lawson responds
"The essence of your point seems to be
the assumption that, while the temperature record over 20 years
(from 1980 to 2000) is immensely significant, the temperature
record over 10 years (the first decade of the 21st century) is of
no significance at all. I know of no scientific basis for this
seemingly arbitrary distinction."
Beddington then writes back
"your representation of my argument does
not accurately reflect what I wrote. The point I was making is that
in order to assess the impact of greenhouse gases on global
temperature, it is necessary to consider the long-term
(multi-decadal) trend…. When we consider the record decade by
decade…it is clear that even allowing for uncertainties in the
observations, that last three decades have each been significantly
warmer than the previous one ie the error bars do not overlap."
Lord Lawson also argues in the first chapter of his book that
global warming has stopped in this century, with global average
temperature higher in 1998 than during any year between 2001 and
2007. Beddington writes
"It is meaningless to compare global
average temperature in any two years within a period of a decade or
two, because natural climate variability can cause temperatures to
fluctuate … 1998 was an unusually warm year, largely due to a
natural climate phenomenon known as an El Niño event."
Lord Lawson also appears to have misunderstand the nature of key
climate feedback processes, writing
I have become increasingly puzzled by
the proposition that warming brings about more water vapour, which
in turn causes more warming, which then presumably produces more
water vapour, and so on ad infinitum. This implies a runaway
instability which, if true, would have made the planet
uninhabitable long ago.
The existence of a feedback in the
climate (or any other) system does not imply a runaway feedback …
the way in which the planet achieves energy balance is more complex
than your simple argument for a runaway instability.
The table below summarises the points covered in the letter,
which cover most of the scientific arguments made in An Appeal to
The scientific material in An Appeal to Reason is based on many of
the most common climate sceptic arguments. Many of the arguments in
the book have subsequently been repeated by Lord Lawson's think
tank The Global Warming Policy Foundation. The GWPF state in their
founding document: "The Object of the Charity is to advance the
public understanding of global warming and of its possible
Beddington's is a Professor of Applied Population Biology. He
appointed as Government Chief Scientific Advisor in January
2008. In the letters and supporting documents, he refers to the
wider body of scientific work and peer-reviewed literature to
correct the claims made by Lawson.
recently wrote in a blog for the New Scientist entitled 'We
need both scepticism and consensus':
It is time the scientific community
became proactive in challenging misuse of scientific evidence. We
must make evidence, and associated uncertainties, accessible and
explicable. In a world of global communication, we cannot afford to
only speak to ourselves. We must also be confident in challenging
the misrepresentation or exaggeration of evidence and the
conclusions it leads to. Where significant consensus exists, it
must be made obvious.
The letters obtained under FOI can be downloaded here.