INTERCOMPARISON OF PULSED LIDAR DATA WITH FLIGHT LEVEL CW LIDAR DATA AND MODELED BACKSCATTER FROM MEASURED AEROSOL MICROPHYSICS NEAR JAPAN AND HAWAII

Aerosol backscatter coefficient data were examined from two nights nea r Japan and Hawaii undertaken during NASA's Global Backscatter Experim ent (GLOBE:) in May-June 1990. During each of these two nights the air craft traversed different altitudes within a legion of the atmosphere defined by the same set of latitude and longitude coordinates. This pr ovided an ideal opportunity to allow flight level focused continuous w ave (CW) lidar backscatter measured at 9.11-mu m wavelength and modele d aerosol backscatter from two aerosol optical counters to be compared with pulsed lidar aerosol backscatter data at 1.06- and 9.25-mu m wav elengths. The best agreement between all sensors was found in the alti tude region below 7 km, where backscatter values were moderately high at all three wavelengths. Above this altitude the pulsed lidar backsca tter data at 1.06- and 9.25-mu m wavelengths were higher than the flig ht level data obtained from the CW lidar or derived from the optical c ounters, suggesting sample volume effects were responsible for this. A erosol microphysics analysis of data near Japan revealed a strong sea- salt aerosol plume extending upward from the marine boundary layer. On the basis of sample volume differences, it was found that large parti cles were of different composition compared with the small particles f or low backscatter conditions.