Radar Observations of the Free Atmosphere: Panel Report

Few radar developments promise to have greater impact on the atmospheric sciences than VHF/UHF radar. Able to monitor motions in the clear air, these instruments provide an unprecedented look at the small-scale structures (in both space and time) of atmospheric winds and the temperature/humidity fluctuations that scatter the electromagnetic radiation. These structures reveal important processes, including instability; atmospheric wave generation, propagation, interaction, and decay; severe weather development and associated mesoscale wind features such as outflow boundaries and midlevel inflows; coupling of the lower and middle atmosphere; and atmospheric turbulence. In addition to their intrinsic kinematic interest, these processes often dominate atmospheric transports and budgets of dynamic and thermodynamic variables such as momentum and energy, water vapor and other trace gases, liquid water, ice, and other aerosols. In the atmosphere, such processes are often event-driven, placing a premium on our ability to observe them with fine spatial and temporal resolution. Already, exploratory use of VHF/UHF radars has provided important new insights to our understanding of atmospheric structure and dynamics. Harnessing such observing systems in the future will significantly improve weather services and expand the possibilities for atmospheric research.