HR: 0800h
AN: ED51D-0041    [Abstracts]
TI: A perspective on the influence that biomass burning may have on cirrus clouds: Freezing of solutions catalyzed by high molecular weight organic compounds
AU: * Robinson, C
EM: cbrobins@mtu.edu
AF: Dept. of Physics Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931
AU: Cantrell, W
EM: cantrell@mtu.edu
AF: Dept. of Physics Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931
AB: Deep convection frequently carries the products of biomass burning into the upper troposphere. A better understanding of this phenomenon would shed light on how the products of the burning are affecting the properties of cirrus clouds. Ice nucleation mechanisms are thought to be the most important property that is being affected by the burning. In biomass burning, aerosol particles are most likely a mixture of organic compounds and salts. We investigated freezing events of sodium chloride and ammonium sulfate solutions, which were catalyzed by heptadecanol or pentacosanol. Both are high molecular weight alcohols that are insoluble in water. The results of the freezing temperatures of the solutions for both organic compounds will be presented as a function of the molarity of the solution. The results will also be discussed in light of Koop et al.'s (2000) assertion that ice nucleation is a function only of the water activity. References: Koop, T., B. Luo, A. Tsias, and T. Peter, Water activity as the determinant for homogeneous ice nucleation in aqueous solutions. Nature, 406, 611-614, 2000.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0320 Cloud physics and chemistry
SC: Education and Human Resourcese [ED]
MN: 2004 AGU Fall Meeting