So the world is going to end today — or so say some interpretations of an ancient Mayan calendar. But how?
Well, if you’re still here, look to the sky. The most plausible scenario for instant apocalypse is from outer space.
That’s what likely did in the dinosaurs. A meteorite crashed into Mexico’s Yucatan peninsula about 65 million years ago, spewing dust, ash and steam into the sky, triggering massive tsunamis as well as earthquakes and volcanic eruptions.
Debris filled the atmosphere, the theory goes, blocking the sun’s rays and dramatically altering the ecology.
But don’t worry. Nothing that big is going to sneak up on us.
“We would have seen it by now,” said Bob Allen, a retired astronomy professor at the University of Wisconsin-La Crosse who runs the school’s planetarium.
What about the theory that it’s simply hiding behind the sun?
Maybe plausible before the space age, Allen said, but orbiting satellites have eliminated blind spots.
Eventually the sun itself will expand as it ages, incinerating the earth. But that’s another 5 billion years off.
Allen points out that the sun throws off solar flares from time to time and reverses its magnetic polarity roughly every 11 years.
OK, but what about:
A home-grown catastrophe is more likely, said Jeff Bryan, a professor of chemistry who teaches nuclear science at UW-L.
The United States and Russia have big enough stockpiles of nuclear weapons to do considerable damage, Bryan said, but probably not total global destruction.
“I think we could do a pretty good job on the northern hemisphere,” he said. “There might be some post-apocalyptic future for the southern hemisphere.”
Even so, it would take people on both sides to push the button as there have been dozens of accidents but no explosions, Bryan said. “We’ve been pretty sloppy with them and we haven’t been able to get one to detonate.”
And as for the world’s roughly 450 nuclear power plants, Bryan points out that even the 9.0 magnitude Fukushima earthquake didn’t trigger meltdowns; it was the subsequent tsunami.
Even in a worst-case scenario, in which multiple plants melt down, Bryan said, the result would be localized contamination.
Truly apocalyptic damage would require an unimaginable earthquake.
“That’s going to kill everybody anyway,” Bryan said. “We wouldn’t be around to notice.”
Earth, wind and fire
Just how likely is such an earthquake? Not very, said Mike Blanpied, associate coordinator for the U.S. Geological Survey’s earthquake hazard program.
“We really don’t know of any geologic process that could cause disruption on that scale,” he said.
Earthquakes can cause big upheaval, but the vicinity is limited. The largest known quake was a 9.5 magnitude temblor that struck off the coast of Chile in 1965, killing 1,655 people there and dozens more in Pacific islands hit by the tsunami.
The rupture zone of that quake was about only 600 miles long.
The greater concern for USGS scientists are earthquakes that hit vulnerable cities in developing nations with dense populations and lax building standards or a massive quake centered near one of the world’s biggest cities.
“Tokyo is our biggest fear,” Blanpied said. “A direct hit of 8.0 on Tokyo is a trillion dollar impact on the global economy.”
Unfortunately, there’s no reliable way to predict earthquakes, although scientists can calculate probabilities and craft building codes to meet realistic scenarios.
Blanpied’s associates at the USGS Volcano Hazard Program have a little better forecast capabilities.
Much like the weather, they can’t predict what will happen years from now, but volcanoes — there are 169 active ones in the United States — usually give off signals hours if not weeks before they erupt.
“It’s rare for us to be caught by surprise by eruptions if we have the equipment (in place),” said Peter Cervelli, a USGS vulcanologist.
There haven’t been any earth-changing eruptions in recent times, though a supervolcano 75,000 years ago on the island of Sumatra spewed debris 30 miles into the sky, dropping ash over much of the Indian Ocean and even onto the Tibetan plateau.
That eruption — about 2,500 times larger than the 1980 Mount St. Helen’s explosion — put a big hurt on the human race, changing landscapes and horticulture, said Charles Mandeville, program coordinator for volcano hazards at USGS.
Still, “It didn’t wipe us out,” he said. “We’ve moved on.”
Mother Nature may have the best chance of doing us in, but not today.
Climate models suggest stronger and more frequent storms are the new norm — along with a tendency to more droughts, said Stephen Vavrus, a senior scientist at the Center for Climatic Research at the University of Wisconsin-Madison.
He’s been researching the potential for heavy rainfalls to trigger outbreaks of water-borne illness, a likelier scenario than a biblical flood.
Even under new climate models, Varvus said, “a single storm wouldn’t devastate half the U.S. all at once.”
The real cause for concern is rising sea levels. Oceans are expected to swell by about a meter as global temperatures rise.
While virtually certain, that change may take 100 years; unfortunately it could take hundreds if not thousands more years to reverse.
“There’s really no end in sight for something like that,” Vavrus said.
So what’s with the end-of-the-world predictions?
Likely a misunderstanding of Mayan calendar, which runs out today, said Robert Glenn Howard, an associate professor of communications at UW-Madison and associate director of the Folklore Program there.
Howard, who has been studying end-of-times movements since the 1990s, said there’s no evidence the ancient Mayans believed anything bad would happen at the end of the cycle.
“Most scholars today think they would have seen it as a good thing,” Howard said. “It would be like 1999. It’d be a very celebratory thing.”
Howard said the majority of believers are hoping for a spiritual transformation, and for them the day will likely be a positive experience. The “preppers” hunkered down expecting a cataclysmic event will be most disappointed.
As for Howard, he received a grant to travel to Chichen Itza, the sacred Mayan site where thousands of believers are expected to gather. Instead he’ll be at home with his wife, who’s expecting their first child today.
Howard said, “I’m kind of hoping he’s born so he can say his birthday is on the great 2012 solstice.”