Mark Hertsgaard in The Nation:

They say that everyone who finally gets it about climate change has an “Oh, shit” moment–an instant when the full scientific implications become clear and they suddenly realize what a horrifically dangerous situation humanity has created for itself.

It’s especially alarming when people who, ahem, know their shit, speak about their own personal “Oh Shit” moment.

Take Hans Joachim Schellnhuber, chair of an advisory council known by its German acronym, WBGU, and a physicist whose specialty is chaos theory.

Speaking in July at an invitation only conference in New Mexico, Schellnhuber divulged the findings of a study so new he had not yet briefed Chancellor Angela Merkel about it.

Schellnhuber and his WBGU colleagues’ study states that the United States must cut emissions 100 percent by 2020. Yep, that means quit carbon completely within ten years. Germany, Italy and other industrial nations must do the same by 2025 to 2030. China only has until 2035.

The world as a whole must be carbon-free by 2050.

This kind of timetable is lightyears from what the IPCC is proposing, and failing to get agreement on.

But even this “brutal” timeline of the WBGU study, Schellnhuber admitted, wouldn’t guarantee staying within the 2C target. It would merely give humanity a two-out-of-three chance of doing so–“worse odds than Russian roulette …But it is the best we can do.”

To have a three-out-of-four chance, countries would have to quit carbon even sooner.

“I myself was terrified when I saw these numbers,” Schellnhuber said. Hans’ suggestion to push past that rising “Oh Shit” feeling and avert paralysis? “War-time mobilisation.”

So, time to share: what’s produced your latest “Oh Shit” moment? Or have you, like many of the Australians polled in the latest Lowy Institute survey, managed to ignore the bad news and pushed climate change down the list of your concerns, to, oh, seventh — just behind job security, the economy, terrorism and the threat of nuclear weapons?

Oh, shit.