Nigel Calder, sadly no longer with us, closely followed the global warming fraud during his career, and made many constructive observations on it.
His concept of the Hall of Shame, for fraud promoters, is always worth a read.
"Hall of Shame
Retracing those 14 years, what if physics had functioned as it is supposed to do? What if CLOUD, quickly approved and funded, had verified the Svensmark effect with all the authority of CERN, in the early 2000s. What if the Intergovernmental Panel on Climate Change had done a responsible job, acknowledging the role of the Sun and curtailing the prophecies of catastrophic warming?
For a start there would have no surprise about the “travesty” that global warming has stopped since the mid-1990s, with the Sun becoming sulky. Vast sums might have been saved on misdirected research and technology, and on climate change fests and wheezes of every kind. The world’s poor and their fragile living environment could have had far more useful help than precautions against warming.
And there would have been less time for so many eminent folk from science, politics, industry, finance, the media and the arts to be taken in by man-made climate catastrophe. (In London, for example, from the Royal Society to the National Theatre.) Sadly for them, in the past ten years they’ve crowded with their warmist badges into a Hall of Shame, like bankers before the crash."
http://calderup.wordpress.com/2011/08/24/cern-experiment-confirms-cosmic-ray-action/

In a post, dated Sunday, 29 November 2015, ant writes, "You still have not answered the question as to when fraud began, Leo."

A curious challenge, seeing as how no one in the discussion at that point had ever asked anyone, any such question.

Ant then went on, in the same paragraph, "Arrhenius made predictions at the beginning of the 19 century..."

Ah, not quite right ant. A minor point, but worthy of correcting. It is extremely unlikely that Svante Arrhenius made any predictions at the beginning of the 19th century, because he wasn't born until 1859. Are we talking about the same Arrhenius?

Finally, ant, in the next paragraph, gets around to posing the question to Leo Lane that he'd already been accused previously of not answering. Sheeze. Some questionable logic here.

Anyway, the question ant posed was, "When exactly did the fraud you have pushed for a considerable time commence?"

Now that's a very good question ant. When exactly indeed.

Not wishing to steal Leo Lane's question, I was very interested to ascertain the facts of the matter myself, for personal selfish reasons and even though not invited, I'd like to put forward my views and accredit or blame the perpetrators - depending on your point of view.

Notwithstanding previous political history, of which I'd think there would be some and accepting the basic science regarding CO2 and its abilities of absorption and re-radiation of long wave energy, it seems likely that the "fraud" commenced circa 1970.

Read on...

(Cont)

(Cont)

As the chief orchestrator, I would point my finger at Maurice Frederick Strong.

Refer - https://en.wikipedia.org/wiki/Maurice_Strong
"Strong had his start as an entrepreneur in the Alberta oil patch and was President of Power Corporation of Canada until 1966. In the early 1970s he was Secretary General of the United Nations Conference on the Human Environment and then became the first executive director of the United Nations Environment Programme."

As the main organisation refer - https://en.wikipedia.org/wiki/United_Nations_Environment_Programme
United Nations Environment Programme (UNEP). Formation: 5 June 1972.
"Its activities cover a wide range of issues regarding the atmosphere, marine and terrestrial ecosystems, environmental governance and green economy. It has played a significant role in developing international environmental conventions, promoting environmental science and information and illustrating the way those can be implemented in conjunction with policy, working on the development and implementation of policy with national governments, regional institutions in conjunction with environmental non-governmental organizations (NGOs)."

Yep, all the usual suspects there. But the next bit's somewhat surprising.

"UNEP has also been active in funding and implementing environment related development projects" - such as the Miss Earth beauty pageant! (Worth checking out as a side issue if you like that sort of thing).

And now here's the next bit of the trail, "The World Meteorological Organization and UNEP established the Intergovernmental Panel on Climate Change (IPCC) in 1988."

IPCC - https://en.wikipedia.org/wiki/Intergovernmental_Panel_on_Climate_Change
"The IPCC provides an internationally accepted authority on climate change, producing reports which have the agreement of leading climate scientists and the consensus of participating governments. The 2007 Nobel Peace Prize was shared, in two equal parts, between the IPCC and Al Gore".

Al Gore's Inconvenient Truth or Convenient Lie?

So ant, in answer to your question, I reckon the fraud got under way about 1972 and has followed the above path since. Depending on your political persuation, and nothing to do with genuine science, the above trail sets out the heros or the fraudsters. The fraud is the politics hiding behind the grossly exaggerated "science".

There's nothing new about any of the above, but ant asked for it.

voxUnius,

Indeed, you did find I had made a mistake with my centuries thank you for correcting me, Ahrrhenius (1859 - 1927) was busy with his Physics at the beginning of last century.

Guy Calendar, kept meticulous notes on temperature from around the earth and published that the planet was warming back in 1938. So he was adding information already begun by Fourier, Tyndall and Arrhenius and others.

http://www.climate-lab-book.ac.uk/2013/75-years-after-callendar/

By the 1970s climate science was developing further.

I realize for many the United Nations is seen as some kind of political conspiracy. But in the case of climate science there was already a body of knowledge to back up Maurice Strong.

ExxonMobil's own paper work lets it down in relation to funding denier groups:

https://www.documentcloud.org/documents/1019872-2001-exxon-giving-report.html

http://www.climateinvestigations.org/exxon-http://www.climate-lab-book.ac.uk/2013/75-years-after-callendar/did-cohen

It is my understanding that the Pillippine's Commission for Human Rights is being requested to investigate the role of major fossil fuel companies involved in climate change and its impact on the community.

First sentence:

"In a first, CHR to probe global polluters for rights violations", 4 December 2015
The Commission on Human Rights announced…that it will give due course to a petition filed in the Philippines by various environmental advocacy groups seeking an investigation of 50 international “carbon majors.”

From:

http://business-humanrights.org/en/philippines-carbon-majors-face-national-human-rights-complaint-on-climate-change-for-the-first-time#c128007

The IPCC had skeptic scientist Professor Lindzen, denier economist Richard Tol and ExxonMobil scientists involved with it. Richard Tol has since stated that anthropogenic climate change is real. The conspiracy theory doesn't hold that well when ExxonMobil and skeptics are involved with the IPCC; and also, with science being quite well developed, it does not make much of a conspiracy theory against Maurice Strong. The actions planned by the Phillipines against fossil fuel companies doesn't look good from a PR point of view.
Ken Cohen has pushed hard the message that ExxonMobil were pleased with their scientists, now ExxonMobil own documentation show they funded denier groups (referenced, 2001 being example given, but there are other years also) .

A referencewouldn't open, try this:

http://www.climateinvestigations.org/blog

The particular article is titled.....It’s not just what #ExxonKnew, it’s what #ExxonDid next

HUNT, HARES & HOUNDS

"run with the hare and hunt with the hounds"

Fig. to support both sides of a dispute. In our office politics, Sally always tries to run with the hare and hunt with the hounds, telling both the clerical workers and the management that she thinks they should prevail.

Greg Sheridan - Weekend Australian pages 15/19 5-6 Dec 2015

“When Abbott asked Hunt to stay on, Hunt said he would do so only on certain conditions, Namely, he would endorse climate science. He would never question or oppose the basic science.”

“His acute political insight was simple. When the debate was over belief in the science, Labor won. When the debate was over electricity prices, the Coalition won. The Coalition had to convince the public that it took the science seriously.”

Quite a few folk, however, feel the Minister of the Environment actively supports bad science.

A professor of my acquaintance who can tell wheat from chaff is one of them:

"There was going to be in investigation into whether there had been Bureau of Meteorology falsification of past temperature records. Those of us following closely have seen the evidence gathering for over a year. But the Minister arbitrarily shut down the investigation, giving no plausible reasons."