HR: 09:25h
AN: A31C-06    [Abstracts]
TI: Smoke Plumes Deep in the Stratosphere: Direct Injection or Self Lofting?
AU: * Jensen, E J
EM: Eric.J.Jensen@nasa.gov
AF: NASA Ames Research Center, Mail Stop 245-4, Moffett Field, CA 94035 United States
AU: Ackerman, A S
EM: andrew.ackerman@nasa.gov
AF: NASA Ames Research Center, Mail Stop 245-4, Moffett Field, CA 94035 United States
AB: POAM solar occultation measurements have identified aerosol layers deep in the extra-tropical stratosphere. These plumes can be as high as 18 km (458 K potential temperature) and have been attributed to injection by intense pyrocumulus cloud systems associated with forest fires in Canada and Asia. However, it is not clear whether the pyrocumulus are energetic enough to reach such high altitudes. It has been hypothesized that the smoke plumes might be injected into the lowermost stratosphere, followed by radiative heating and self-lofting to the observed higher altitudes. The fresh smoke particles will efficiently absorb solar radiation, and the potential for lofting will depend on factors such as the heating rates, particle sedimentation rates, and plume dimensions. We will quantitatively evaluate the lofting mechanism and use a three-dimensional model with interactive dynamics, microphysics, and radiative transfer to simulate the lofting for observed plume dimensions and reasonable microphysical properties.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0320 Cloud physics and chemistry
DE: 0321 Cloud/radiation interaction
DE: 0322 Constituent sources and sinks
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005