Atmosphere, ocean in climate dance

Though miles apart, winds high in Earth's upper atmosphere and currents at the bottom of the North Atlantic interact to shape climate, U.S. scientists say. That's the unexpected result of a study that found periodic changes in winds 15 to 30 miles high in the stratosphere influence the seas by striking an area in the North Atlantic vulnerable to cooling or warming of the atmosphere and changing mile-deep ocean circulation patterns, which in turn affect Earth's climate, the University of Utah reported Sunday. "We found evidence that what happens in the stratosphere matters for the ocean circulation and therefore for climate," atmospheric scientist Thomas Reichler said. Events in the stratosphere, 6 miles to 30 miles above Earth, are known to affect what happens below in the troposphere, from Earth's surface up to 6 miles or about 32,800 feet, where most weather occurs, researchers said. Meanwhile, circulation patterns in the oceans -- caused mostly by variations in water temperature and saltiness -- are known to affect global climate. "It is not new that the stratosphere impacts the troposphere," Reichler said. "It also is not new that the troposphere impacts the ocean. But now we actually demonstrated an entire link between the stratosphere, the troposphere and the ocean." There is "a significant stratospheric impact on the ocean," the researchers said. "The weakening and strengthening of the stratospheric circulation seems to correspond with changes in ocean circulation in the North Atlantic," Reichler said. "This leads to the remarkable fact that signals that emanate from the stratosphere cross the entire atmosphere-ocean system," the study concluded.