Can short-wavelength radars improve blind spots in the current operational radar network?

The lowest mile of the atmosphere is a blind spot for the current NWS operational radar network because the effective height of the radar beam increases due to the curvature of the Earth. Unfortunately, it is in the lowest mile where we think tornadoes form. NSSL is participating in an NSF-sponsored Engineering Research Center called the Center for Collaborative Adaptive Sensing of the Atmosphere (CASA) to explore sensing the lower atmosphere with a network of many short-wavelength (3cm) radars. These smaller and less expensive radars will be spaced much closer together than those in the current operational radar network to provide data in these blind spots. CASA will initiate a new observation methodology termed DCAS (Distributed Collaborative Adaptive Sensing). DCAS samples the atmosphere in a focused manner, where and when the need is greatest for end users.

The system of radars that are part of the Oklahoma testbed (called Network Radars or NetRAD) are spaced 30km from each other and are one-fifth the size of a NEXRAD radar. Assembly and integration of the radar transceivers, pedestals, radomes, nodelevel computation and communication electronics of the radars took place at NSSL. In March, 2006, the four NetRAD radars were installed in Rush Springs, Lawton, Cyril, and Chickasha, OK. NSSL's WDSS-II will ingest and process NetRAD data for detection algorithms. The goal of the Oklahoma testbed is to demonstrate DCAS concepts for high temporal and spatial resolution sensing of winds in the lower atmosphere and detecting, tracking, and predicting severe storms, especially tornadoes.