HR: 14:35h
AN: A13F-04    [Abstracts]
TI: Optical Remote Sensing of CCN
AU: * Harrison, L
EM: lee@asrc.cestm.albany.edu
AF: Atmospheric Sciences Research Center, State University of New York, Albany, NY 12203, United States
AU: Min, Q
EM: min@asrc.cestm.albany.edu
AF: Atmospheric Sciences Research Center, State University of New York, Albany, NY 12203, United States
AB: We show a new retrieval algorithm to obtain either CCN concentrations from optical extinction at multiple wavelengths. This is known to be a difficult retrieval problem. We show that it is possible to partially orthogonalize the retrieval against large-particle contributions, which helps substantially. Nonetheless further constraint is necessary. We show the statistics of many dry-aerosol size distributions observed at a rual ridgeline site in eastern New York (Pinnacle Peak). These data are analyzed by fitting them with a distribution dN/dr = C rⁿ/(R + r)^k . The results show that this distribution can fit the observed distributions well, and that we see statistical correlations of the coefficients in these data which we can use to provide climatological constraints for the CCN retrieval. We apply the retrieval with this climatological constraint to four years of extinction data taken at the Atmospheric Radiation Measurement (ARM) program central facility. This retrieval generates plausible CCN numbers most of the time. This argues that the parameterization developed from the aerosol distributions seen at Pinnacle Peak, and thus the climatological constraints fed into the retrieval, are useful at the ARM SGP site, and perhaps more generally to mid continental sites.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0320 Cloud physics and chemistry
DE: 0321 Cloud/radiation interaction
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting