 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
Tibet Provides Passage For Chemicals To Reach The Stratosphere
Pasadena CA (SPX) May 10, 2006 ASA and university researchers have found that thunderstorms over Tibet provide a main pathway for water vapor and chemicals to travel from Earth's lower atmosphere - where human activity directly affects atmospheric composition - to the stratosphere, where the protective ozone layer resides. Researchers at NASA's Jet Propulsion Laboratory, as well as the Georgia Institute of Technology in Atlanta, and the University of Edinburgh, Scotland, used data from the Microwave Limb Sounder instrument aboard NASA's Aura spacecraft, combined with data from NASA's Aqua and Tropical Rainfall Measuring Mission. The team collected more than 1,000 measurements of high concentrations of water vapor in the stratosphere over the Tibetan Plateau and the Asian monsoon region. They collected the measurements during August 2004 and August 2005, during the height of each year's monsoon season. They used wind data and atmospheric models, and found the water vapor originated over Tibet, just north of the Himalayan mountain range. They also found more thunderstorms occurred over India, but the storms over Tibet transported nearly three times more water vapor into the lower stratosphere. "This study shows that thunderstorms over Tibet are mainly responsible for the large amount of water vapor entering the stratosphere," said lead researcher Rong Fu of Georgia Tech's School of Earth and Atmospheric Sciences. "The rainfall may not be as frequent over Tibet as over the Indian monsoon area, but because Tibet is at a much higher elevation than India, the storms over Tibet are strong and penetrate very high, and send water vapor right into the stratosphere." Learning how water vapor reaches the stratosphere can help improve climate prediction models. Likewise, understanding the pathways that ozone-depleting chemicals can take to reach the stratosphere is essential for understanding future threats to the ozone layer, which shields Earth from the Sun's harmful ultraviolet rays. The researchers also found the same pathway is responsible for transporting carbon monoxide, an indicator of air pollution, into the upper atmosphere. "There's almost no carbon monoxide production in Tibet, so it's widely believed that carbon monoxide is transported to the tropopause over Southeast Asia and the Indian subcontinent," Fu said. The tropopause divides the lower atmosphere from the stratosphere, and is located at an altitude of about 18 kilometers (11 miles) above Earth over the tropics and Tibet. Fu said the data show thunderstorms over Tibet transport as much carbon monoxide to the lower stratosphere as do those over India. "When long-lived pollutants are transported out of the lower atmosphere, they can move rapidly," Fu said. "Pollutants from Asia, for example, can wind up on the other side of the world." Community Email This Article Comment On This Article Related Links Aqua Tropical Rainfall Measuring Mission Microwave Limb Sounder Earth Observation News - Suppiliers, Technology and Application
Raytheon Tests Advanced Space-Based Weather Sensor
El Segundo CA (SPX) May 10, 2006Raytheon announced Tuesday it is performing space-qualified vacuum testing on a prototype of the Visible Infrared Imaging Radiometer Suite, a key instrument in NOAA's National Polar-orbiting Operational Environmental Satellite System. |
|
|
| The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement |
