PITTSBURGH, March 5 (UPI) -- U.S. scientists say particulate matter may be having a greater influence on global climate than previously thought.
Carnegie Mellon University Professors Allen Robinson and Neil Donahue report a new conceptual model for how microscopic particles behave in the atmosphere that raises new questions about current regulations.
The research found new chemical processes that occur after soot and gaseous pollutants are emitted from cars and trucks, changing the chemical and physical properties of the soot particles and creating new particulate matter.
Those new particles, say the researchers, are potentially more toxic and may have a stronger influence on cloud formation that can alter the global climate.
"For the longest time, particulate matter has been the least understood component of the climate system," said Donahue. "The more we understand particulate matter, the more we realize that complexity has been masking our ability to calculate how big a role greenhouse gases have played in inducing global warming."
The study appears in the March 2 issue of the journal Science.
