Research Infrastructure: Mid-scale RI-1 (MI:IP): Dual-Doppler 3D Mobile Ka-band Rapid-Scanning Volume Imaging Radar for Earth System Science

This NSF Mid-scale Research Infrastruture-1 project is for the development of two mobile cloud and weather radars, known as the Ka-band Rapid-scan Volumetric Imaging Radars (KaRVIR). Ka-band refers to the short, millimeter-scale wavelength of the radar transmissions, which are ideal for observing small particles in the atmosphere. A primary use case for the radars will be for the remote sensing of cloud processes including the development of precipitation. Existing cloud radars only point vertically or have a slow scan rate for a full volume scan. KaRVIR will use phased array radar technology to provide a generational leap in measurement capability, completing a volume scan in less than 20 seconds. This will allow for the capture of quickly developing cloud processes which cannot be observed by any other means. The development will enable first-of-its-kind studies of cumulus cloud evolution, cloud and precipitation processes, atmospheric boundary layer structure, and wildfire studies, among many other topics. The development takes advantage of prior public and private sector investments in advanced wireless technology and addresses key NSF priorities regarding national defense, disaster response, and the Established Program to Stimulate Competitive Research (EPSCoR). Student training will take place at the intersection of atmospheric sciences and engineering. KaRVIR is a next generation phased array radar system for atmospheric and related sciences. The antenna arrays will employ a conventional design based on mature and commercially available technology using slotted waveguide array architecture. Individual elements on the antenna will be used to transmit a fan beam with 17° elevation fixed beamwidth, which can be mechanically steered to obtain a full 0-90° field of view. Digital beamforming will provide excellent temporal resolution (<20 s), spatial resolution (24 m at 5 km), and radar sensitivity (-26 dBz at 5 km). The two radars can be used in dual-Doppler configurations to provide measurements of vertical air motion. The radar will help to answer critical questions about the different theories of atmospheric convection (a plume vs a succession of thermal “bubbles”), explaining the formation of drizzle through the warm rain process, secondary ice production, and fire-atmosphere interactions. As an advanced use of the technology, the research team will attempt first-of-its-kind turbulence measurement in three dimensions over a larger scale of view than is currently possible. This project is jointly funded by NSF’s Mid-scale Research Infrastructure-1 program and the Established Program to Stimulate Competitive Research (EPSCoR). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.