References

NHESS

Natural Hazards and Earth System Sciences

NHESS

Nat. Hazards Earth Syst. Sci.

1684-9981

Copernicus Publications

Göttingen, Germany

10.5194/nhess-10-295-2010

<i>Brief communication</i> "Modeling tornado dynamics and the generation of infrasound, electric and magnetic fields"

Schmitter

E. D.

Faculty of Engineering and Computer Science, University of Applied Sciences Osnabrueck, Albrechtstr. 30, 49076 Osnabrueck, Germany

16 02 2010

10 2 295 298

2010

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://nhess.copernicus.org/articles/10/295/2010/nhess-10-295-2010.html

The full text article is available as a PDF file from https://nhess.copernicus.org/articles/10/295/2010/nhess-10-295-2010.pdf

Recent observations endorse earlier measurements of time varying electric and magnetic fields generated by tornadoes and dust devils. These signals may provide a means for early warning but together with a proper modeling approach can also provide insight into geometry and dynamics of the vortices. Our model calculations show the existence of pressure resonances characterized as acoustic duct modes with well defined frequencies. These resonances not only generate infrasound but also modulate the charge density and the velocity field and in this way lead to electric and magnetic field oscillations in the 0.5–20-Hz range that can be monitored from a distance of several kilometers.

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