Greenhouse gas more common than thought

LA JOLLA, Calif., Oct. 23 (UPI) -- The U.S. space agency says new research indicates a powerful greenhouse gas might be at least four times more prevalent than has been thought.

The research, based on data from a National Aeronautics and Space Administration-funded study, focused on nitrogen trifluoride. That greenhouse gas is thousands of times more effective at warming the Earth's atmosphere than an equal mass of carbon dioxide, NASA said.

Researchers led by Ray Weiss of the Scripps Institution of Oceanography, made the first atmospheric measurements of nitrogen trifluoride, which was estimated in 2006 at less than 1,200 metric tons. The new research showed about 5,400 metric tons of the gas are in the atmosphere and it is increasing at a rate of about 11 percent per year.

"Accurately measuring small amounts of nitrogen trifluoride in air has proven to be a very difficult experimental problem, and we are very pleased to have succeeded in this effort," Weiss said.

Emissions of nitrogen trifluoride were thought to be so low the gas has not been considered a significant potential contributor to global warming.

The findings are to appear in the Oct. 31 issue of the journal Geophysical Research Letters.