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1 comment

Interesting, but.. (1)

JWSmythe (446288) | more than 2 years ago | (#37402628)

Interesting story, but it fails to observe some obvious facts.

1km = 3,281 feet. They claim to use a water pump available at any hardware store. With a pump at ground level, and a balloon at 1km, it would require 1,420psi or about 9790 kPa. At your average hardware store (i.e., the ones I've been in, and looked at pumps), I don't recall anything near that.

The largest pump I could find on Lowes or Home Depot web sites was for up to 125 feet of lift. You might be saying "But my pressure washer does better than that!" Of course it does. It reduces the volume of water, and increases the velocity. So you're getting 3,000 psi from something the size of a pinhole. That sounds perfect, except for the fact that if they hope to make something with the surface area resembling the cloud from a volcano, they need ... well ... something the size of a cloud from a volcano. Something say the size of the Mount St. Helens eruption. A 1 mile wide, 12 miles tall spray, that spreads out for hundreds of miles. A little something like this []

The 1km altitude isn't going to do it either, so that 1420psi number is way too low. They're trying to reproduce light being reflected by the higher altitudes. That's not going to happen quite as well as they'd like from 1km. Try at least 40x that.

Even though it doesn't have to reproduce the volume, it does have to reproduce the reflectivity. For what they're demonstrating, they'd make a better reflection by covering your roof with aluminum foil. :)

If they're hoping to do it from a municipal water supply, they'd better think again, unless none of the people there really wanted drinking water (or showers, or toilets that flush).

If they use water from the Atlantic, they'd have to desalinate it first. Otherwise, they'd do a wonderful job of spreading salt over a vast area. (hint: salt and most land plants don't get along well). Farmers and even regular citizens who like having a lawn, won't be very happy.

They'd be better off doing something to increase the evaporation of water from the ocean.

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