By November 2006, Populus found that more than half of us (53 per cent) were willing to pay significantly higher petrol prices, car tax and air fares to cut back on carbon emissions. A whopping 74 per cent agreed that, “Environmental issues like climate change are very important to me and will influence how I vote at the next election”. Wow.

What happened? A number of things. The rising oil price had started to tune even relatively wealthy people back into the whole question of energy use, just as it had done in the Seventies. The election of David Cameron to the leadership of the Conservative Party in November 2005 made green rhetoric a staple of all the main parties for the first time. Media coverage also grew exponentially, making people more aware of unusual weather patterns: every freak storm or flood was linked to greenhouse gases.

David Attenborough started telling the nation about climate change through his BBC series Life in the Undergrowth. The oil giant BP plastered the world with adverts about the warming planet, and even Lisa and Bart Simpson went on a school trip to a glacier that had melted. By the time David Cameron was pictured with huskies on the Arctic ice-sheet on April 21, he was surfing a new public mood. The photos were published everywhere, with worthy commentary about melting sea-ice.

It was like a dam breaking. Until 2006, all the reports and dire warnings seemed to have been piling up to no avail. In July 2005, Tony Blair had given Africa and climate change top billing at the Gleneagles summit. But it was Africa that stuck in everyone’s mind. Mr Blair toned down the green language in deference to the White House.

Only a dedicated few were even aware of moves by backbench MPs to create a Climate Change Bill – and political correspondents had no interest. Then, all of a sudden, at the start of the year, every magazine seemed to be running features on eco-chic.

For me, the first indication of a seismic shift came in January 2006 when my father happened to mention global warming as if it were the most natural thing in the world. I could barely speak. This was a man who for years had been embarrassed and often annoyed by my obsession with environmental issues.

Not long after that I wrote a column arguing for taxing airlines. The response was overwhelming. Even those who were hostile to air taxes were generally accepting of climate change as a reality. The argument had moved from the science to equity and economics.

If 2005 ended with politicians running ahead of public opinion, 2006 ended the other way round. Al Gore’s An Inconvenient Truth was cresting a wave when it opened in September. And when Sir Nicholas Stern’s review was published on October 31, the Treasury was genuinely taken aback by the response.

A dry economist became a household name almost overnight and his 700-page tome, stating that the costs of climate change would far outweigh the costs of rapid action to prevent it, was a talking point all over the place. But who really lit the flame of consciousness in the first place? I asked an expert. “Jeremy Clarkson [the keeper of the flame for the anti-eco set] was the best thing that could have happened to climate change,” says Solitaire Townsend of the communications consultancy Futerra.

Which may prove that humans are much less interested in dire warnings than in sheer bloody gall.

2006 was the year that video on the web went mainstream, but what were people actually watching? Click here to see The top 10 YouTube videos of 2006

Read more from A Year in Ideas here:
It's the videos, stupid
The return of realpolitik
Bossy TV
Science fights back
Sporno
Proustian sports channel
Barbarians back at the gate
Global spa-ification
Graphic novels
Conscience consumerism
End of the blockbuster
Bad Russians are back
Rock'n'roll is dead, long live rock'n'roll
Fashionable adoption
TB or not TB
The new clubbing
Bistrodeluxe
Wikitravel
Return of the musical