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steve2470

steve2470's Journal
steve2470's Journal
August 30, 2019

"Why don't we try to destroy tropical cyclones by nuking them ?"

I know we here at DU already know the answer to this (unlike our Dictator wannabe) but here's the full answer:


https://www.aoml.noaa.gov/hrd/tcfaq/C5c.html

Subject: C5c) Why don't we try to destroy tropical cyclones by nuking them ?
Contributed by Stan Goldenberg and Hugh Willoughby

During each hurricane season, there always appear suggestions that one should simply use nuclear weapons to try and destroy the storms. Apart from the fact that this might not even alter the storm, this approach neglects the problem that the released radioactive fallout would fairly quickly move with the tradewinds to affect land areas and cause devastating environmental problems. Needless to say, this is not a good idea.

Now for a more rigorous scientific explanation of why this would not be an effective hurricane modification technique. The main difficulty with using explosives to modify hurricanes is the amount of energy required. A fully developed hurricane can release heat energy at a rate of 5 to 20x1013 watts and converts less than 10% of the heat into the mechanical energy of the wind. The heat release is equivalent to a 10-megaton nuclear bomb exploding every 20 minutes. According to the 1993 World Almanac, the entire human race used energy at a rate of 1013 watts in 1990, a rate less than 20% of the power of a hurricane.

If we think about mechanical energy, the energy at humanity's disposal is closer to the storm's, but the task of focusing even half of the energy on a spot in the middle of a remote ocean would still be formidable. Brute force interference with hurricanes doesn't seem promising.

In addition, an explosive, even a nuclear explosive, produces a shock wave, or pulse of high pressure, that propagates away from the site of the explosion somewhat faster than the speed of sound. Such an event doesn't raise the barometric pressure after the shock has passed because barometric pressure in the atmosphere reflects the weight of the air above the ground. For normal atmospheric pressure, there are about ten metric tons (1000 kilograms per ton) of air bearing down on each square meter of surface. In the strongest hurricanes there are nine. To change a Category 5 hurricane into a Category 2 hurricane you would have to add about a half ton of air for each square meter inside the eye, or a total of a bit more than half a billion (500,000,000) tons for a 20 km radius eye. It's difficult to envision a practical way of moving that much air around.

Attacking weak tropical waves or depressions before they have a chance to grow into hurricanes isn't promising either. About 80 of these disturbances form every year in the Atlantic basin, but only about 5 become hurricanes in a typical year. There is no way to tell in advance which ones will develop. If the energy released in a tropical disturbance were only 10% of that released in a hurricane, it's still a lot of power, so that the hurricane police would need to dim the whole world's lights many times a year.

August 20, 2019

Robot coffee tastes great, but at what cost ? (about $5)

https://www.wired.com/story/coffee-haus-robot-coffee/

Airports have robot coffee now.

But first, consider that moment—you’ve experienced this—where your multiply delayed flight finally lands, maybe at the airport you expected and maybe not. Then you realize, taxiing across the tarmac, that it is in fact the middle of the night. So picture the terminal, the one in which you are alone. The Hermès shop is not open. The massage place is kneadless. The food court is no longer in session. Should airports also be shopping malls? I don’t know. Right now this one, which usually is, isn’t.

Let’s say you’re at San Francisco International Airport, Terminal 3, across from the Yankee Pier fish place. There’s a signpost, up ahead. A glowing beacon in the night. Since early August, a touchscreen has offered lonely travelers a mug o’ mud—exuded by the sleek, cargo-container-sized structure looming next to it. This is a “Coffee Haus,” brown, horizontal window on one side, big touchscreen on the other, and in the middle, a white-framed presentation space. As the great architect and known caffeine abuser Le Corbusier would definitely have said, “a Coffee Haus is a machine for coffee.”

A hundred times an hour, it can make a coffee drink. Kevin Nater, CEO of Briggo, the company that builds Coffee Hauses (Häussen?), says a fully staffed Starbucks can only do one coffee drink a minute. Sixty an hour—and that’s with human people! All that stuff about “third places” and interpersonal interactions, the thing where hey, you wanna get a coffee, the Coffee Haus burns all that away.
August 16, 2019

Putin: "Hey Oleg, I bet you 50 rubles I can make him think Greenland is for sale."

Putin: “Hey Oleg, I bet you 50 rubles I can make him think Greenland is for sale.”

Oleg: “C’mon, Vlad. Nobody’s that stupid.”

Putin: “Oh, but he is. Watch.”

*fifteen minutes later*

Trump: “Imma buy Greenland.”

Putin: https://twitter.com/elle_desylva/status/1162228387487727616

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