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The average wind speed at 30 ft height was measured at 19 sites in the Western Kansas region during June 1980–July 1982. Two things were noted from the measurements. First, NWS measured average wind speeds in the region for the same period were about 1.1 mph higher than those measured at the 19 sites. A NWS model anemometer was calibrated, and when the calibration results were applied to the NWS data, the difference was largely removed. Second, there was considerable variation between the measured average wind speeds at the 19 sites, even though the sites were fairly close together, had similar surface cover near each site, and had only very small elevation changes around the towers. An attempt was made to reduce the difference between the measured average wind speeds by a correction based on the small elevation features in the 10-mile radius area surrounding each measurement tower. This measurement correction significantly reduced the differences in the measured wind speeds.

Properties of a side-looking airborne radar (SLAR) designed for geoscience rather than military use are presented. The speckled nature of usual single-frequency radar images may be reduced by averaging in azimuth and by averaging in range or transmitting excess range bandwidth. With synthetic aperture systems, averaging is possible in both range and azimuth, but only range averaging (excess bandwidth) is reasonable with most real-aperture systems. Multispectral sensing appears to offer advantages for radar comparable with those for photography, on the basis of experimental spectral response curves. Matching the transfer characteristics of receiver, recorder, and film is necessary to achieve quality images. Special techniques may be necessary to permit discriminating targets of similar radar return while at the same time allowing for the very wide total range of returns. The calibration necessary to achieve repeatable results and permit use of automatic data processing may be obtained by inserting a stepped sample of transmitter signal into the receiver to place calibration blocks on the image. Both multiple look-angle coverage with a single flight line and stereo can be achieved by use of fore-and-aft squinted antennas for alternate transmissions.