NOAA / CC BY 2.0

The threat of tornadoes in America's midwest could be eliminated by building three huge walls, according to physicist Rongjia Tao.

Tao, from Temple University in Philadelphia, unveiled his proposal at the American Physical Society meeting in Denver. According to his analysis, the walls would slow the movements of air in the region enough to prevent tornadogenesis. "If we build three east-west great walls, one in North Dakota, one along the border between Kansas and Oklahoma, and the third in the south in Texas and Louisiana, we will diminish the threats in Tornado Alley forever," he said. The walls in question would be 300 metres high and as long as 160 kilometres.


The idea is not to shelter towns directly -- the walls would not be strong enough to stand up to a tornado -- but to stop them from forming in the first place. "We may not have east-west mountain ranges - like the Alps in Europe - we can build walls," he said.

Tao proposes that the walls be decorated attractively so as not to be an eyesore. "Our tornado wall could even be built of glass.

It could be a beautiful landmark," he said. "I spoke to some architects and they said it's possible. It would take a few years to finish the walls but we could build them in stages."

However, meteorologists have poured scorn on the idea. "Everybody I know is of 100 percent agreement - this is a poorly conceived idea," said Joshua Wurman from the US Centre for Severe Weather Research. He added that the walls, if built, would significantly change the climates of the areas. "The cure could be worse than the disease," he told BBC News.