Physics
Scientific paper
Dec 2002
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002agufm.p51a0335d&link_type=abstract
American Geophysical Union, Fall Meeting 2002, abstract #P51A-0335
Physics
3304 Atmospheric Electricity, 3322 Land/Atmosphere Interactions, 3394 Instruments And Techniques, 5409 Atmospheres: Structure And Dynamics
Scientific paper
In this work we discuss observations of the electrical structure of dust devils made in the summer of 2001 and 2002 during the Mars Atmosphere and Dust in the Optical and Radio (MATADOR) field campaign outside of Tucson, Arizona. While it has long been known that Terrestrial dust devils can support large electric fields of magnitudes of up to 10 kV/m or more, the fundamental features of the charging mechanism have yet to be fully characterized from an observational perspective. If triboelectric charging is indeed responsible for the generation of significant electric potentials within the dust column, some means of large scale stratification and/or separation of charges is necessary to maintain these fields. To help address this question and elucidate the overall vertical charge distribution of dust devils, we used two field mill instruments to make simultaneous measurements of electric fields both at the surface and 1 meter above the ground. At present, our observations indicate that the dust grains become negatively charged at or very near the air-surface interface. The largest devils recorded (30 m diameter) show a region of enhanced positive electric fields persisting for minutes after the event has passed, indicating the possible presence of a large scale collection of airborne positive charges following the negatively charged dust column. Based on our observations, the key to the charging mechanism appears to reside in the bottom of the saltation layer where the bulk of collisional frictional charging is likely to occur. We discuss the implications of these observations for theories of Terrestrial dust devil electrification and for our understanding of similar processes on Mars.
Delory Gregory T.
Eatchel A.
Farrell William M.
Hillard Barry
Marshall Jonathan R.
No associations
LandOfFree
The Electrical Structure of Terrestrial Dust Devils: Implications of Multiple Vertical Measurements of the Electric Field does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Electrical Structure of Terrestrial Dust Devils: Implications of Multiple Vertical Measurements of the Electric Field, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Electrical Structure of Terrestrial Dust Devils: Implications of Multiple Vertical Measurements of the Electric Field will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1892102