ATLANTA, Nov. 7 (UPI) -- U.S. scientists have found a potentially important mechanism by which chemical emissions from ocean phytoplankton influence cloud formations.
Discovery of the new link between clouds and the biosphere grew from efforts to explain the increased cloud cover observed over an area of the Southern Ocean, where a large bloom of phytoplankton was occurring.
After studying satellite data the researchers hypothesized airborne particles produced by oxidation of the chemical isoprene, which is emitted by the phytoplankton, might have contributed to a doubling of cloud droplet concentrations seen over a large area of ocean off the eastern coast of South America.
The scientists estimate the resulting increase in cloudiness reduced the absorption of sunlight by an amount comparable to what has been measured in Earth's highly polluted areas.
If confirmed by field studies, the connection between clouds and biological activity could add a critical new component to global climate models.
The study by Athanasios Nenes of the Georgia Institute of Technology and Nicholas Meskhidze, formerly at Georgia Tech but now at North Carolina State University, appears in the Nov. 2 edition of Science Express, the online advance publication of the journal Science.
