Boundary layer dynamics and associated entrainment rates of heat and water vapor over a pasture site in amazonia

As part of the NASA Tropical Rainfall Measuring Mission (TRMM) in Rondonia, Brazil during the wet season months of January and February 1999, we investigated the dynamics of the convective boundary layer. The gathered observations are unique because of the completeness of surface and balloon-borne instrumentation, the high vertical resolution of sounding measurements, the collocation of tower, radiation, and tether-sonde measurement systems, and the presence of a ground-based radar. The data sets allow for detailed studies of mixed layer moisture budgets and interactions between the surface and overlying atmosphere. In this presentation we will report the principal features controlling the dynamics of the convective boundary layer over continental tropics of Brazil. We will also report the results of modeling studies in describing both dynamics of the mixed layer and entrainment rates of heat and water vapor. Finally, we will outline newly develop algorithms of mixed layer processes to more accurately describe entrainment rates of heat and moisture.