Harry Turtledove - Supervolcano - All Fall Down

More than he wanted to live with his mother ever again. That pretty much settled that.

“Yes, this was a large eruption, even by supervolcano standards-nearly six hundred cubic miles,” Kelly Ferguson told her class at Cal State Dominguez Hills. “This was just about the size of the first Yellowstone eruption, more than two million years ago, and almost as big as the Mount Toba blast in Indonesia seventy-five thousand years ago.” She paused. “Anybody remember how many times the Yellowstone supervolcano blew between that first big boom and this last one?”

Anybody remember? was a prof’s shorthand for How many of you did your reading? A couple of tentative hands went up. Kelly pointed at one of them. The owner of the hand, a big, broad brown guy she guessed was a Samoan, said, “Uh, two?”

He didn’t sound very sure, but he was right. She beamed at him. “Good!” she said.

He looked relieved. If she remembered how he’d done on the last quiz, he had reason to look that way. The State University was California’s second tier, behind the University of California. Students here came in two kinds: the ones who couldn’t get into the UC system, and the ones who couldn’t afford it. Some of the latter bunch were as good as anybody who did get into the University of California. The others. . mostly weren’t. Kelly’d done enough TAing to know the kind of work UC students did. Too many of these kids couldn’t come close to that standard.

Well, you did what you could with what you had. She went on, “Both those other eruptions were still enormous. Even the smaller one ejected about sixty-four cubic miles of rock and dust and ash. That’s four times the size of the blast from Mount Tambora, back two hundred years ago, and Mount Tambora’s the volcano that gave the United States and Europe what they called the Year Without a Summer.” She glared out at them. “And anybody who mixes up Mount Tambora and Mount Toba is in big trouble, you hear? Mount Tambora is still there. One of these days, it’ll go off again. What used to be Mount Toba is Lake Toba now-the volcano blew itself to hell and gone. One of these days, it’ll go off again, too, but I pretty much promise we won’t have to worry about it. We’ve got enough other things to worry about.”

The kids laughed nervously, for all the world as if she were kidding. They scribbled notes. Some of them just recorded what she said, so they could listen to it again before the test. She’d always thought putting the material into her own words helped make it hers. She still did, but she’d come to see not everybody worked the same way. Recording sure was easier than taking notes.

“Okay,” she said. “The smallest Yellowstone eruption was four times the size of the one from Mount Tambora-and Mount Tambora was pretty big for an ordinary volcano. How much bigger than that ‘little’ supervolcano eruption was this last one?”

She waited. She’d told them how many cubic miles of ejecta the Yellowstone supervolcano’d belched this last time. Now they had to remember that or find it in their notes and make the calculation. Calculators and cell phones came out. Doing math in your head wasn’t quite so obsolete as writing in cuneiform, but it came close.

A girl in the front row indignantly hit what had to be the CLEAR ERROR button. Either she’d made a mistake or she didn’t believe the answer she’d got. A skinny black guy tentatively raised his hand. Kelly nodded to him. “Nine times?” By the way he said it, he had trouble believing it, too.

But Kelly nodded again. “That’s right,” she said. The girl in the front row looked disgusted, so she must have thought a right answer was wrong. Well, it was pretty unbelievable, all right. “If you spread the ash and dust and rock evenly all over California, it would be about twenty feet deep.”

The ones who wrote wrote that down. Of course, the ejecta weren’t spread evenly. Lava and pyroclastic flows-the really dense stuff-stayed relatively close to the supervolcano caldera. But relatively was a relative term. Jackson, Wyoming, lay maybe sixty miles south of what had been the southern edge of Yellowstone National Park. Today, it was as one with Pompeii and Herculaneum. One of these centuries, it would probably astonish archaeologists.

There was a hell of a funny book, one whose author she couldn’t remember, called Motel of the Mysteries . It was all about the stupid conclusions excavators with no cultural context would jump to when they dug up a twentieth-century motel. It also made you wonder how much of what you thought you knew about ancient Egypt was nothing but bullshit. Well, Jackson-and a good many other towns-would give future diggers their chance at dumbness.

A girl who could have been anything and probably was an L.A. mutt-a little bit of everything-raised her hand. “Question?” Kelly asked.

“Uh-huh,” the girl said. “Somebody told me you were, like, in Yellowstone when the supervolcano went off. Is that right?”

“Um, no,” Kelly answered. “If I’d been there then, I wouldn’t be here now. Trust me on that one.” The class laughed nervously. She decided she needed to say more: “I was part of a team of geologists doing research in the park while the supervolcano was ramping up. A couple of helicopters flew us out when things started looking really scary. We’d just landed in Butte, Montana, about two hundred miles away, when it blew. I was on the runway-I mean, we’d just landed. The earthquake knocked me over, and then the wind-the blast wave, if you want to think of it like that-blew out most of the windows in the terminal, blew me down the strip, and knocked my copter over on its side.”

“From two hundred miles away?” the girl said. “Wow!”

“Wow,” Kelly agreed. “Yeah, from two hundred miles away. It’s-what? — eight hundred miles from Yellowstone to L.A., and you guys heard the blast here, right?” She knew Colin had. Hell, they’d heard it across the whole country. They’d heard it in Western Europe.

“We felt the quake, too,” the girl replied. “We felt it before we heard the boom.”

Kelly nodded. “You would have. Earthquake waves travel faster than sound.”

“I thought the world ended,” the skinny black kid said. “Way things’re at right now, maybe I wasn’t so far wrong, either. Snow in L.A.? If that ain’t the end of the world, what is it? Anybody know for sure how long the cold weather’s gonna last?”

Regretfully, Kelly shook her head. “Anywhere from a few years to a few hundred years. No one can tell you any closer than that. We’ve never had a supervolcano go off before when we were equipped to study it.”

The big Samoan guy raised his hand. When Kelly pointed to him, he asked, “While you were in that helicopter just before the big eruption, were you, like, y’know, scared?”

“No shit!” Kelly blurted.

The undergrads burst into startled laughter. They didn’t expect that kind of language from a prof, even one who wasn’t all ancient and dusty. But what else could you say when somebody sent you a really silly question? Maybe they’d decide she was a human being after all. It might be too much to hope for, but maybe.

“You’ve got to remember, the hot spot under the supervolcano has been active a lot longer than it’s been under Yellowstone-under what used to be Yellowstone.” Kelly had loved the park, loved hiking in it, loved the geological formations without a match anywhere in the world. All gone now. The ecosystem would be tens-more likely hundreds-of thousands of years healing. “It started up under northeastern Oregon seventeen or eighteen million years ago. As the North American tectonic plate slid along on top of it, it erupted every so often across Idaho till it got to where it is now. The Snake River Valley follows the path of the eruptions pretty well.”