The researchers, professor of atmospheric physics Giles Harrison and applied meteorologist Kieran Walesby, describe their device in the AIP's Review of Scientific Instruments. The instrument consists of a 2-meter-long and 1-meter-wide Rokkaku-type kite -- a simple-to-construct Japanese kite design with "good stability, reasonable load-carrying capacity, and a low sink rate when the wind speed drops," Harrison says -- attached to a ground-based strain gauge that monitors the tension in the kite's tether line. That line tension, Harrison and Walesby found, is linearly related to wind speed.
"The kite method is portable and cheap, and removes the need for a mast to support an anemometer," Harrison says. "A particular use is to provide measurements above those reached by masts" -- although, he adds, "it will work less well at low levels, or in very turbulent conditions. We expect to refine the kite design to allow operation in a wider range of conditions, and to encourage wider adoption of our approach."