Combining statistical analysis of solar wind data from the Advanced Composition Explorersatellite, which measures solar particles approaching Earth, with a series of magnetohydrodynamic simulations, used to model the behavior of the Earths magnetosphere, Borovsky characterizes the properties of the shear layers that travel past the Earth and the reaction of the Earth to those passing layers.
The author finds that as many as 60 of these shear zones can pass by Earth each day at velocities above 50 kilometers per second (31 miles per second). Passage of a shear layer perturbs the entire magnetosphere and ionosphere, which could produce a comet-like disconnection of the Earths magnetotail (the tail-like extension of Earths magnetic field on the side facing away from the Sun). Although the velocity shears will not cause a geomagnetic storm, they may determine how such a storm works. Hence, the author recommends several follow-up studies of the reaction of Earth to sudden wind shear.
More information: The effect of sudden wind shear on the Earth’s magnetosphere: Statistics of wind shear events and CCMC simulations of magnetotail disconnections Journal of Geophysical Research-Space Physics, doi:10.1029/2012JA017623 , 2012
American Geophysical Union
Article source: http://phys.org/news262971171.html