“Oh, that’s space weather,” Johnny Greene said. “Ngaen Xong Hoa’s work is on planetary weather systems, and he’s the prime researcher in the field. Although last I heard, even he hadn’t solved the chaos aspects.”
“Who cares about planetary weather?” Markel demanded. If dirtsiders didn’t like being rained on, why didn’t they live in space like all sensible folk?
“Markel,” Johnny said sharply, “stop pouting and use your brains! I know you’ve got some, heard ‘em rattling round in there just the other day. Turn on a couple of processing bits, will you? Okay, so space colony ships like Haven don’t care about dirtside weather, neither do lunar colonies or high-tech cities in domes. But there are still plenty of people out there who live by growing food or raising animals on planetary surfaces, who have to guess right about the upcoming weather if they and their children are going to eat next year. Ninety percent of Khang Khieaan’s habitable surface is good agricultural land; naturally they care about knowing whether it’s going to rain enough to raise their crops … or enough to drown them.”
“Sounds like a simple enough question to me,” said Market. “Just model the atmosphere and the ground surface and plug in your numbers. Nothing like as complicated as plotting a course through four-space to shortcut from one quadrant to another without meeting a neutron star.”
“You think so, do you?” said Johnny. “Well, here. I’ll give you references to the latest weather-modeling theories, and you can download a complete data set on Khang Kieaan’s current weather. We’ll likely be here another two-three shifts to collect Hoa, so you’ll have plenty of time to predict … oh, the rainfall over the Green Sea, and the expected high temperature in the central plains area, that’ll do for starters. Just take a look at the models, decide which one works best, and … what was it you said? … plug in the numbers. Then we’ll see how close you came.”
Markel hadn’t come to Johnny for extra homework, but he’d learned that if he did what Johnny Greene suggested, it usually worked out to his benefit in the long run. Besides which, once Johnny had given him a learning assignment like that he wouldn’t talk to Market at all, not even to tell tales of mining adventure among the asteroids, until Markel could show that he’d done the work. So he copied the references over to his private storage files, set the system to download Khang Kieaan’s current weather data, and skimmed papers on weather modeling while he waited for the data to come in.
He was waiting when Johnny came off duty two shifts later. “This stuff is crazy,” he complained. “Look, I programmed three different models-well, okay, I didn’t have to do them from scratch, most of the code was in files attached to the papers -and fed in the same numbers, and look at the results! This one says the Green Sea is going to get two inches of rain between dawn and noon tomorrow, this one says thirty percent chance of typhoons and doesn’t tell me anything about rain, and this one”-he waved the printout for emphasis-“this one only says, ‘If a butterfly flutters its wings in the rain forest, what is the probability of snow in Alaska?’”
Johnny laughed. “Okay. Welcome to chaos theory. That last one is telling you it doesn’t have enough data.”
“I gave it the same data set the others had.”
“It’s more persnickety. The other two models are designed to give you their best guesses regardless of how close on they are – sort of the way traditional weathermen operate. This third one”-Johnny tapped the printout-“won’t give a prediction that can’t be relied upon. And it just happens that planetary weather is what we call a chaotic system-meaning that its adjacent solutions diverge exponentially in time. Such a system is very sensitive to the initial conditions, which means that a very slight change in the starting point-like the fluttering of a butterfly’s wing-can lead to enormously different outcomes.”
“Then this last model is a joke,” Markel muttered.
“Nope. It’s making a point: that none of the existing models is accurate. Did you look at the author’s name?”