TODAY, another bloated United Nations conference to "stop" global warming. And, oops, another leak of emails to warn we've been conned.

Two years ago the UN's Copenhagen summit - to unite the world in cutting global emissions - became a laughing stock when thousands of emails were leaked from the Climatic Research Unit of Britain's University of East Anglia (UEA).

They revealed top climate scientists in Britain and the US were fiddling research, censoring sceptics and hiding data from checks.

The significance of that scandal was played down. Now it's on again.

Today in Durban, thousands of climate scientists and lobbyists meet for the latest stop of the gravy train known as the UN's Intergovernmental Panel on Climate Change.

But an anonymous leaker has again spoiled the party, last week releasing 5000 emails from the UEA, many involving the same clique of climate scientists who have done most to convince us man's gases are heating the world dangerously.

That theory was already in trouble thanks to the failure of the world to warm over the past decade, but these emails reveal even leading warmists privately admit they have a problem.

Take Asher Minns, manager of Britain's Tyndall Centre for Climate Change Research: "Global warming freezing is already a bit of a public relations problem with the media."

Other emails show an unease about the hyping of the warming scare.

US climate scientist Tom Wigley writes: "There have been a number of dishonest presentations of model results by individual authors."

Peter Thorne, who worked at Britain's Met Office, warns colleagues against claiming the tropical troposphere is warming, and adds: "I think science is manipulated to put a political spin on it."

Others show scientists pushing a "cause" rather than investigating a theory.

Prof Michael Mann, whose now-discredited "hockey stick" graph was promoted by the IPCC to "prove" the world's temperature had never risen this fast, attacks a fellow warmist scientist who's asked inconvenient questions: "I gave up on Judith Curry a while ago. I don't know what she thinks she's doing, but it's not helping the cause."

Other climate scientists indeed helped "the cause", not least by defending Mann and his iconic graph, showing flat temperatures for thousands of years, followed by a huge uptick last century.

As the UEA's Dr Douglas Maraun complains: "How should we deal with flaws inside the climate community? I think that 'our' reaction on the errors found in Mike Mann's work were not especially honest."

The leaked emails give a powerful impression of a tight group of scientists convinced of their "cause" and stifling even their own doubts.

More amusingly, it shows some asserting with arrogance what's proved nonsense since.

Take David Jones, a prominent alarmist with our own Bureau of Meteorology.

In 2007 he wrote to the head of the UEA's Climatic Research Unit, Phil Jones, claiming our drought as evidence of global warming.

"Truth be know (sic), climate change here is now running so rampant that we don't need meteorological data to see it," he gloated.

"Almost every one of our cities is on the verge of running out of water and our largest irrigation system (the Murray-Darling Basin) is on the verge of collapse ... "

But what does our Climate Commission now concede about the drought that Jones claimed showed we'd heated the planet?

It says the drought, now broken, was not unusual after all: "Australia naturally has a high degree of variability in rainfall ... so it is difficult from observations alone to unequivocally identify anything that is distinctly unusual about the post-1950 pattern."

As Climate Commissioner, Will Steffen confirmed to me: "We've had very severe droughts before so again we cannot attribute this drought statistically to climate change" or Jones's claim that global warming meant "almost every one of our cities is on the verge of running out of water".

Check the levels of our water storages: Sydney is at 78 per cent, Melbourne 65, Canberra 96, Adelaide 77 and Perth 36 (with a second desalination plant being built). Brisbane water catchments are at 79 per cent even after a quarter of its stored water was released to prepare for floods.

In short, not one city is "on the verge of running out of water". The Murray-Darling Basin is in excellent shape after last summer's floods with its storages at 87 per cent.

The real world was already making fools of the warming catastrophists who have for so long dominated the debate and shut out the sceptics.

Now these emails let the rest of us into the joke.

Originally published as In on the joke of an inconvenient truth