The investigators propose continued operation and development of the Flatland Radar Observatory, near Champaign- Urbana, Illinois. The principle instrument at the Flatland Observatory is the 50 MHz ST radar; it is presently supported by a surface meteorological station, a radiosonde, and an array of eight microbarographs. This instrumentation will be supplemented with a 915 MHz lower tropospheric radar and an accompanying Radio Acoustic Sounding System (RASS) to measure wind and temperature profiles in the lower troposphere. The scientific objectives are: (1) to investigate mesoscale dynamical processes in the troposphere and lower stratosphere and their effects on larger scale dynamics; (2) to study microscale processes, including turbulence and stratified irregularities of refractive index, and to assess their effects on the accuracy and precision of ST radar measurements; and (3) to assess the capabilities of the ST radar technique, particularly its potential for measuring vertical velocities over extended times.
