Earth's Atmosphere "Breathes" More Rapidly Than Thought
Earth’s atmosphere was known to "breathe" in a cycle lasting nearly a month. Now scientists say the planet takes a quick breath every few days.
The breathing-like activity is the result of high-speed solar wind disturbances that cause a recurrent expansion and contraction of Earth’s atmosphere every few days, satellite observations show. This atmospheric mode could affect radio communication, orbiting satellites and possibly the Earth's climate, researchers say.
The expansion and contraction happens way up in the Earth's thermosphere, the layer of the atmosphere that extends from about 60 to 300 miles (96.5 to 483 kilometers) above the planet's surface. The thermosphere is constantly interacting with the sun's upper atmosphere as it expands out into the solar system, said one of the researchers who made the discovery, Jeff Thayer of the University of Colorado in Boulder, during a press conference at the annual meeting of the American Geophysical Union in San Francisco yesterday.
This interaction causes an energy exchange that can change the density of the thermosphere (how closely the gas molecules within it are packed together). As its density changes, the thermosphere expands and contracts.
(cont'd on site)