Aerosol profiles at SGP - How much do we miss?

Aerosol profiles at SGP - How much do we miss?

Lidar profiles at SGP

We can use remote sensing data (i.e., lidar) to estimate how much aerosol we miss by only doing profiles up to an altitude of 3.5 km. Raman lidar profiles of aerosol extinction are used to compute the aerosol optical thickness (AOT) at the Raman lidar wavelength of 355 nm between the surface and 7 km (or cloud base, whichever is lower). These profiles represent the AOT below a given altitude and have been normalized to unity at 7 km. These profiles were computed as a function of AOT; the histograms represent the frequency of occurrence of a particular range of AOT. Raman lidar data collected during 1998 and 1999 were used for these analyses. The Raman lidar methods to derive aerosol extinction are explained in the article "Automated retrievals of aerosol extinction and backscatter coefficient profiles from a Raman lidar" by Turner, Ferrare, Heilman, Feltz, and Tooman, which has been submitted to J. Appl. Meteor. Additional details may also be found from the ARM 10th Science Team extended abstract "Characterization of the Atmospheric State above the SGP Using Raman Lidar and AERI/GOES Measurements".

AOT_HIST1.GIF

Larger version of figure

This figure is from David Turner's presentation "A Two-Year Climatology of Water Vapor and Aerosols in the Lower Troposphere Measured by a Raman Lidar" by David Turner, Richard Ferrare, Lorraine Heilman, Tim Tooman, Oleg Dubovik presented at 20th International Laser Radar Conference in Vichy, France, July 10-14, 2000.