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The application of clear-air radars to operational wind profiling is considered. Several alternative techniques for determining atmospheric winds from radars are surveyed and, in light of the current interest in operational applications, the current status of the techniques is summarized and the need for more research and development knowledge before defining any final system configuration stressed. Finally, some possibilities for portable automated systems of the future are suggested.

, a total of 11 cases of human plague have been reported in residents of six states: Arizona (two), California (one), Colorado (four), Georgia (one), New Mexico (two), and Oregon (one). The two cases in Georgia and California residents have been linked to exposures at or near Yosemite National Park in the southern Sierra Nevada Mountains of California. Nine of the 11 patients were male; median age was 52 years (range = 14-79 years). Three patients aged 16, 52, and 79 years died. Plague is a rare, life-threatening, flea-borne zoonosis caused by the bacterium Yersinia pestis. During 2001-2012, the annual number of human plague cases reported in the United States ranged from one to 17 (median = three cases) (1). It is unclear Readers who have difficulty accessing this PDF file may access the HTML file at

The variability of small-scale atmospheric turbulence on time scales from a few minutes to the annual scale and at altitudes from about 4 to 20 km is studied using clear air Doppler radar data from Poker Flat, Alaska, and Platteville, Colorado. The variable used for this study is the refractivity turbulence structure constant Cn 2. The frequency distribution of Cn 2 is found to be lognormal during all seasons at all altitudes. Using data at 4-min intervals, it is found that the autocorrelation function of Cn 2 can be modeled as the sum of a first-order autoregressive process and a random process. The associated integral time scale decreases with altitude from 25 to 45 min in the troposphere to about 18 min in the stratosphere. The power spectrum of log C• • follows a power law relation with frequency; at periods greater than about 2 hours the spectral slope is near -5/3 and at periods less than 2 hours the slope is near -1. Monthly mean values of log C• 2 are largest in the winter and show a secondary maximum in summer. The winter peak is apparently related to increased jet stream and baroclinic storm activity, and the summer peak is believed to be due to convective activity. The correlation of 3-hour values of C• • with wind speed over monthlong periods ranges as high as 0.8 and has a median value near 0.3. During certain periods, C• 2 also depends on other variables such as boundary layer inversions and gravity wave activity. Monthly mean values of Cn 2 correlate more closely with an indicator of the intensity of gravity wave activity than with wind speed or the coarse-scale wind shear. The meteorological significance of these results is discussed briefly.