Photo by Akuppa John Wigham.

If you like cool weather and not having to club your neighbors as you battle for scarce resources, now’s the time to move to Canada, because the story of the 21st century is almost written, reports Reuters. Global warming is close to being irreversible, and in some cases that ship has already sailed.

Scientists have been saying for a while that we have until between 2015 and 2020 to start radically reducing our carbon emissions, and what do you know: That deadline’s almost past! Crazy how these things sneak up on you while you’re squabbling about whether global warming is a religion. Also, our science got better in the meantime, so now we know that no matter what we do, we can say adios to the planet’s ice caps.

For ice sheets — huge refrigerators that slow down the warming of the planet — the tipping point has probably already been passed, Steffen said. The West Antarctic ice sheet has shrunk over the last decade and the Greenland ice sheet has lost around 200 cubic km (48 cubic miles) a year since the 1990s.

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Here’s what happens next: Natural climate feedbacks will take over and, on top of our prodigious human-caused carbon emissions, send us over an irreversible tipping point. By 2100, the planet will be hotter than it’s been since the time of the dinosaurs, and everyone who lives in red states will pretty much get the apocalypse they’ve been hoping for. The subtropics will expand northward, the bottom half of the U.S. will turn into an inhospitable desert, and everyone who lives there will be drinking recycled pee and struggling to salvage something from an economy wrecked by the destruction of agriculture, industry, and electrical power production.

Water shortages, rapidly rising seas, superstorms swamping hundreds of billions of dollars’ worth of infrastructure: It’s all a-coming, and anyone who is aware of the political realities knows that the odds are slim that our government will move in time to do anything to avert the biggest and most avoidable disaster short of all-out nuclear war.

Even if our government did act, we can’t control the emissions of the developing world. China is now the biggest emitter of greenhouse gases on the planet and its inherently unstable autocratic political system demands growth at all costs. That means coal.

Meanwhile, engineers and petroleum geologists are hoping to solve the energy crisis by harvesting and burning the nearly limitless supplies of natural gas frozen in methane hydrates at the bottom of the ocean, a source of atmospheric carbon previously considered so exotic that it didn’t even enter into existing climate models.

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So, welcome to the 21st century. Hope you packed your survival instinct.