The electric field of a New Mexico dust devil


  • W. D. Crozier


On August 21, 1962, a continuously recording inverted field mill, installed on an open semidesert area near the NMIMT campus, recorded the passage of a fairly large dust devil at a time when I was present to make visual observations. Its closest approach to the field mill was about 450 m, established by reference to power line poles and roads. The bulk of the visible dust cloud was contained roughly in a vertical cylinder estimated to have a diameter of 20 m and a height of 120 m. Experience acquired in observation of many other dust devils suggests that the vortex must have extended far above the height of 120 m; in this case the part above this height was not visible against the mountain background and the dust density in it was probably relatively low.