The Center for Collaborative Adaptive Sensing of the Atmosphere (CASA) is a National Science Foundation Engineering Research Center created in fall 2003. Led by the University of Massachusetts at Amherst with several partners including the University of Oklahoma, CASA is establishing a revolutionary new paradigm in which systems of distributed, collaborative, and adaptive sensor (DCAS) networks are being developed to overcome fundamental limitations in current approaches – particularly the inability to sample the lower parts of the atmosphere.

In the first phase of its research program, CASA is emplacing test beds of small, inexpensive, low-power Doppler weather radars – sited on existing infrastructures such as cell phone towers – to test the DCAS concept. The first such network, called NETRAD and consisting of 4 dual-polarization, mechanically-scanning Doppler radars, will begin operating in central Oklahoma in summer 2005. This network will be expanded to 9 phased-array radars in late 2006. Unique to these systems is their ability to dynamically adjust their scanning strategies and other attributes, in a collaborative manner with neighboring radars, to sense multiple atmospheric phenomena while simultaneously meeting multiple end user needs – all in a theoretically optimal manner.

In this paper we assess the ability of a single CASA radar, as well as multiple radars with overlapping scans, to observe tornadoes of various sizes. Specifically, we vary the radar beam width, range, and radial resolution to create a distribution of radar pixel size across the coverage area. We then compare this distribution with a proxy for tornado size, as a function of F-scale, using the 52-year climatology of damage path widths compiled by the NCEP Storm Prediction Center (under varying assumptions about the relationship between tornado size to path width). We present the results as statistical probabilities and as cumulative distribution functions and also discuss the likelihood that a tornado will pass through the 4-node and 9-node NETRAD test beds in Oklahoma.