BOULDER, Colo., March 25 (UPI) -- A U.S.-led team of scientists says it has determined monsoons are lifting Asian pollutants into the stratosphere, where they encircle the Earth.
Investigators at the National Center for Atmospheric Research said their finding provides additional evidence of the global nature of air pollution.
Using satellite observations and computer models, the research team said it determined vigorous summertime circulation patterns associated with Asian monsoons rapidly transport air upward from the Earth's surface. The vertical movements provide a pathway for black carbon, sulfur dioxide, nitrogen oxides and other pollutants to ascend into the stratosphere, about 20-25 miles above the Earth's surface.
"The monsoon is one of the most powerful atmospheric circulation systems on the planet, and it happens to form right over a heavily polluted region," says NCAR scientist William Randel, the study's lead author.
Once in the stratosphere, the pollutants circulate around the globe for several years, Randel said, noting the finding also suggests the impact of Asian air pollution might increase due to growing industrial activity in China and other rapidly developing nations.
The research that included scientists from Canada and the United Kingdom appears in the online journal Science Express.
