Atmospheric electricity during sand storms

TitleAtmospheric electricity during sand storms
Publication TypeJournal Article
Year of Publication1928
AuthorsCanfield R.H.
Date PublishedMay 3, 1928
Keywordsatmospheric electricity, electrical disturbance, sandstorms
AbstractThe Jornada Range Reserve, near Las Cruces, NM, is an experiment station maintainedby the U.S. Forest Service for the purpose ofstudying range problems. Since grazing studies areparamount, the station laboratory is not equipped with instruments used to measure electrical energy. However, the article entitled “Electricity from the Air" which appeared intheNewsSupplement of Science, March 30, 1928, brings to mind some very interesting observations that were made recently at the Jornada headquarters. Numerous stories are circulating throughout the region regarding the electrical phenomena that occur during sandstorms. These accounts vary with the personal characteristics of the storyteller. Some versions are no more than drab, conservative statements. Others are displayed in a glamorous setting of colorful phrases and artistic profanity. All of them deal with a near electrocution of some luckless cowboy while placing the coffee pot on the camp stove during a sandstorm or with automobiles becalmed by static under similar climatic conditions. The first tangible proof observed by the writer that these accounts were not without foundation was obtained during a severe storm on April 4, 1928. On the afternoon of that day, the sandstorm reached its peak of violence between 3 and 4 o'clock in the afternoon. During this time the sky was cloudless. The first evidence of an electrical disturbance was observed in the vacuumtube lightning arrester on the office telephone. Between the carbons of this device, a strong electric arc would form and continue uninterrupted for a period of about 30 seconds. When the arc was broken, it was immediately followed by another arc of the same general character. The radio receiving set was the second object of concern. This instrument is equipped with a 75-ft, multi-strand copper aerial which is elevated about 20 ft above ground. Both the aerial and the telephone wires extend in anorth and south direction, which places them at right angles to the strong west wind. The receiving set was disconnected from the ground and aerial. The tip of the lead-in wire from the radio antenna was placed near the tip of the ground wire. An electric arc resulted immediately. By varying the distance between the wires, it was found that 3.5 centimeters was the maximum width of the gap over which an arc would form. With this arrangement of the wires, the arc was consistent and would continue for a period of 30 seconds without a visible break. When they did occur, the breaks were of short duration. The path of the arc varied in its course between the ground and antenna tips, much after the manner of chain lightning.