Climate change sceptics last week co-opted Margaret Thatcher into their lobbying campaigns, illustrating once more the strong ideological streak that drives their efforts.

Viscount Christopher Monckton of Brenchley has posted, on the blog operated by former TV weatherman and prominent "sceptic" Anthony Watts, a personal account of his influence on Lady Thatcher's views about climate change during the 1980s. Thatcher shocked the UN in 1989 with a call to action on man-made global warming, but has since made sceptical public statements about anthropogenic climate change.

As we have come to expect, Viscount Monckton's recollection of events makes for interesting reading.

He begins with the claim that: "I gave her advice on science as well as other policy from 1982-1986, two years before the IPCC [Intergovernmental Panel on Climate Change] was founded", pointing out that the prime minister's policy unit at that time had just six members and that he was "the only one who knew any science". Monckton then goes on to suggest that "it was I who – on the prime minister's behalf – kept a weather eye on the official science advisers to the government, from the chief scientific adviser downward".

This revelation might be news to Lady Thatcher. On page 640 of her 1993 autobiography Margaret Thatcher: The Downing Street Years, the former prime minister describes how she grappled with the issue of climate change, referring only to "George Guise, who advised me on science in the policy unit". Indeed, given Monckton's purportedly crucial role, it seems to be heartless ingratitude from the Iron Lady that she does not find room to mention him anywhere in the 914-page volume on her years as prime minister.

Viscount Monckton also modestly notes that he was responsible for bringing in "the first computer they had ever seen in Downing Street", on which he "did the first elementary radiative-transfer calculations that indicated climate scientists were right to say some 'global warming' would arise as CO2 concentration continued to climb".

It is perhaps surprising that this novel and important innovation by Viscount Monckton was not recognised by the current minister for science and universities, David Willetts, who was also a member of the prime minister's policy unit between 1984 and 1986. In 1986, "Two Brains" wrote a prize-winning essay on the role of the unit, but mysteriously omitted to mention Monckton's historic contribution.

Viscount Monckton also includes an amusing anecdote:

"In 1988 it was my successor at No. 10, George Guise, who travelled one bitterly cold October weekend down to Chequers, the prime minister's country house, and sat in front of a roaring fire writing the speech that would announce a government subsidy to the Royal Society to establish what would become the Hadley Centre for Forecasting. George remembers how he and the prime minister chuckled at the irony of writing a speech about 'global warming' on an evening so cold that he could hardly hold his pen."

But although her autobiography notes that she did indeed spend two weekends with George Guise working on her first speech about climate change and the environment, this was actually delivered to the Royal Society on 27 September 1988. And it was not until a year later, in a speech to the United Nations in November 1989, that she announced the establishment of "a new centre for the prediction of climate change".

However, Christopher Monckton has not been the only "sceptic" to recently explore the origin of Lady Thatcher's views on climate change. In The Sunday Telegraph last weekend, Christopher Booker praised her as "one of the first and most prominent of 'climate sceptics'", pointing out that that her 2003 book Statecraft includes a section on climate change that "amounts to an almost complete recantation of her earlier views.

But Booker neglects to mention some curious aspects about the arousal of Lady Thatcher's "scepticism" over climate change. At the start of the book's passage on Hot air and global warming, she notes that there is "a vast amount of highly technical material on these matters" but points out that "thankfully, the issues have been clearly analysed and debated by scholars in the United States" before providing a long list of publications by "free market" lobby groups, such as the Cato Institute and the Heritage Foundation.

In her description of the science, the former prime minister draws heavily on a pamphlet called A plain English guide to climate change which was published in December 1997 by the Reason Foundation, another lobby group that the following year received $70,000 from Exxon to "assess public policy alternatives on issues with direct bearing on the company's business operations and interests".

The Reason Foundation's document includes the following statement:

"It is widely acknowledged that the potential temperature changes predicted by global warming theory do not pose a direct threat to human life. Human beings, and a myriad of other organisms, exist quite comfortably in areas with temperature ranges more extreme than those predicted by global warming models."



The former prime minister's book draws heavily on such leaflets produced by US lobby groups, instead of scientific papers, and she refers only briefly to the work of the IPCC, which she was instrumental in bringing about, dismissing its 2001 report as "alarmist".

But Lady Thatcher reveals her true concerns by claiming that "the new dogma about climate change has swept through the left-of-centre governing classes", and warning that the international effort to tackle climate change "provides a marvellous excuse for worldwide, supra-national socialism."

It is this attempt by the former prime minister, who is now 84, to justify her "scepticism" on the grounds of political ideology that perhaps explains why Booker and Monckton feel comfortable using her now to boost their own efforts to influence the public debate on climate change.

• Bob Ward is policy and communications director at the Grantham Research Institute on Climate Change and the Environment at London School of Economics and Political Science.