SAN FRANCISCO Scientists from the Department of Energy's Pacific Northwest National Laboratory will present their research at the 2010 American Geophysical Union Fall Meeting, which runs Monday, Dec. 13 through Friday, Dec. 17 at the Moscone Convention Center in San Francisco.
SPLAT unearths complex view of airborne particles
Measuring individual particles instead of the average reveals a complex landscape
Climate researchers trying to characterize aerosol particles tiny bits of organic molecules, sulfate, dust, soot and more are limited to measuring averages, missing the fact that particles come in many different colors and shapes. SPLAT, an instrument partly developed in EMSL, DOE's Environmental Molecular Sciences Lab at PNNL, can determine the size and composition of individual particles ranging from 50 nanometers (about the size of a small virus) to 3 microns (at least 10 times thinner than the thinnest hair). In Sacramento, Calif., PNNL's Josef Beranek and colleagues used SPLAT for a month to measure the sizes of 195 million particles and the chemical composition of a 10-million-particle subset. They found that particles in Sacramento, though very small, change in size and composition throughout the day in a nearly reproducible pattern. Also, at any point in time, the atmosphere holds a complex mixture of them. The researchers saw particles with organic chemicals mixed with sulfate, from wood-burning, with soot and sea-salt both fresh and aged, and different types of dust. Because particles with different chemistries affect the climate differently, the more intricate view should improve computer models of the atmosphere. (Contact: Mary Beckman, firstname.lastname@example.org, 509-375-3688.)
A131-03: The Diurnal Cycle of Particle Sizes, Compositions, and Densities observed in Sacramento, CA during CARES Field Campaign, Monday, Dec. 13, 2:10 p.m., Moscone West, Room 3002. NO
|Contact: Franny White|
DOE/Pacific Northwest National Laboratory