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Totally Impractical 'Great Walls' Proposed for the Midwest's Tornado Problem

ByAllison EckNOVA NextNOVA Next

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The United States is tornado central. Last year, it had 811 twisters, compared to Europe’s 57. Storm experts are constantly searching for new ways to limit the presence of tornadoes in the Midwest, but for the most part their research has focused on prediction.

Now, though, a physicist claims to have engineered a solution: A series of giant walls.

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Temple University’s Rongjia Tao explains in a new paper , published in the International Journal of Modern Physics B, that we could build three east-west “great walls” reaching some 1,000 feet high and stretching 150 feet wide. These walls—one in the Dakotas, one in Louisiana and Texas, and a third in between—would prevent tornadoes from forming. They’d span the length of about a mile each, and they’d only cost approximately $160 million.

Physicist Rongjia Tao has proposed building three giant walls in the Midwest to limit the formation of tornadoes.

Here’s John Timmer, writing for ArsTechnica:

Tao’s idea is simple: interfere with the flow of air. And since it’s easier to get in the way of air flowing close to the ground, he suggests targeting the northward flow of air. All we need to do is build a giant wall that runs east-west, about 300 meters high (that’s about 1.5 times the height of the Westeros wall) and 50 meters wide. That wall would disrupt the northward flow of air enough to block the intense turnover that spawns tornadoes while still allowing air to flow north and produce rain.

Timmer acknowledged that his coverage of the proposal was meant to highlight just how outlandish it is, but atmospheric scientists have chimed in and debunked the idea for good measure. Alan McStravick— writing for RedOrbit—spoke with Jacob Wycoff, a metereologist for EarthNetworks, the company behind the popular WeatherBug app. He said that Tao’s paper lacks a basic understanding of how tornadoes form. “A one-thousand foot wall doesn’t address high altitude air masses,” he said. Instead, Tao’s research only addresses the need to decelerate converging air masses.

What’s more is that Tao is using China as evidence for why these great walls would work. China’s Eastern Plains, he writes, are bordered to the north and south by east-west running mountain ranges that supposedly aid in breaking up warm and cold air masses, as well as another east-west range smack in the middle of the plain which tapers near the Pacific coast to flatland. The plain is a “mini tornado alley,” he says, suggesting that without the middle range, the entire region would be rife with tornadoes. But what Tao doesn’t acknowledge is that China’s moisture content isn’t the same as the United States’. Plus, tornadoes do enter mountainous regions—take West Virginia, for example.

Moreover, walls this large could create farming and infrastructure problems. Here’s McStravick:

Taking the more measured approach, Wycoff stated, “You can’t just hop into something as massive as this without understanding the negatives. You will have local-scale issues with sun and wind.” Continuing, he asked, “Would the walls prevent wind from powering wind farms that have already been invested in?” Discussing the physics of natural land barriers and other obstructions, Wycoff explained how rain occurs as clouds are forced over structures. “Are you forcing the climate downwind to get rain and the side on the other side of the wall to get none,” he posited. “It could have drastic effects on people who rely on current rain models for farms or livestock.”

In sum, $160 million is probably better used on developing better prediction technology and constructing more architecturally sound buildings and homes rather than building three walls of questionable efficacy.

Watch "Deadliest Tornadoes" streaming online to learn why the 2011 tornado season in the U.S. was so extreme.