How mountains stir up a hot spot of turbulence. Aircraft finds atmospheric gravity waves bending toward Antarctica's polar vortex.
Hand, Eric
For about 2 decades, researchers have known that a region near 60° South, along the Drake Passage between the tip of South America and Antarctica, is the planet's hot spot for so-called gravity waves. They have long suspected that the waves (not to be confused with the gravitational waves rippling through space) are launched by the mountains of the southern Andes and the Antarctic Peninsula, which jut thousands of meters into westerly winds. But puzzlingly, the hot spot lies hundreds of kilometers away from the mountains. Now, a high-altitude aircraft has traced newborn gravity waves rising from the mountains and bending, or refracting, toward that hot spot. The phenomenon helps explain why climate models predict unrealistically cold temperatures over the South Pole. That, in turn, could improve forecasts of seasonal weather and of the ozone hole that develops over Antarctica in the southern spring. </p>
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