| Aerosols have been receiving increasing attention for two main reasons. First, their effects on the global radiation budget, both direct and indirect, are now understood to be substantial, and the difficulty in measuring their properties and distribution is the single largest source of uncertainty in calculations of global warming and climate change. Second, the interference of the atmosphere in satellite-based measurements of Earth surface properties is large and the variability is dominated by aerosols. In order to better understand the present and future states of the environment it is important to be able to measure the spatial and temporal distribution and optical properties of aerosols. My work has focused upon measuring the vertical distribution of aerosols over the oceans. In this dissertation I describe several new techniques for the analysis of lidar data and their application to data collected during ACE-Asia (Asian Pacific Regional Aerosol Characterization Experiment). The intensive field phase of this experiment was conducted in the spring of 2001 in and around the Sea of Japan. The field phase included a variety of instruments on land, sea and air measuring physical, optical and chemical properties of aerosols during a period of especially high dust levels in the atmosphere. The lidar system described in this dissertation was located aboard the NOAA Research Vessel Ronald H. Brown between March 14 and April 20, 2001. The lidar ACE-Asia data products include aerosol layer heights and thicknesses, aerosol optical depths, aerosol volume extinction and backscatter coefficients at 523 nm wavelength vs. altitude and corresponding extinction-to-backscatter ratios (“lidar ratios”). Improvements in the reliability (reduced uncertainty) of these data products is demonstrated based on improved inversion techniques. These data are also correlated with other data products collected on the cruise. |
