[Ernest_at_the_Beach]

Just something of interest in the latest Popular Science...pg 56...Jerry Goldstein ...Space Weatherman...He showed why Earth's natural plasma shield isn't as stable as we hoped....

See this:

Space Weather Bulletins

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But Jerry Goldstein of the Southwest Research Institute in San Antonio, Anthea Coster of MIT’s Haystack Observatory in Westford, Massachusetts, and Toni Mannucci of NASA’s JPL in Pasadena, California, used the receivers to measure conditions in the ionosphere--the layer of the atmosphere where the Sun’s ultraviolet light kicks electrons away from their atoms and leaves positively charged ions behind.
The ionosphere’s electric fields delay GPS radio signals as they pass from satellites to receivers. By comparing the different delays of GPS signals with different frequencies, the researchers calculated how many charged particles the signals passed on their way to the receiver. In other words: they measured the thickness of the ionosphere.
Charged particles also play the lead role in geomagnetic storms. During these storms, the Sun spews out a part of its outer layer, which may head toward Earth. This hot cloud of electrons and ions--plasma--then collides with Earth’s doughnut-shape magnetic field.
This collision deforms the cocoon and blows away part of its plasma as a long, tapering plume.
Geomagnetic storms can have noticeable consequences on Earth. On the ground, the changing magnetic field can induce damaging voltages in long power lines. In the ionosphere it can a deteriorate of the quality of radio broadcasts.
While monitoring the state of the ionosphere all over the globe during a couple of storms in 2001 and 2003, Coster and her colleagues discovered this disruption of the ionosphere is far from chaotic.
Changes in Earth’s magnetic field, which stays connected to the plume as it is pushed away, cause powerful electric fields in the outer layers of the atmosphere. An electric “footprint“ of the plume drags over the ionosphere, much like a cold front moves through a weather system.
When such a disturbance occurs over North America, it takes the form of a southeast-to-northwest corridor, a few hundred miles wide, where radio reception suffers. Along its edges, GPS readings may be off by tens of yards instead of just a few.

The PS article talks about Goldstein's use of the NASA Image satellite to that during the most severe solar storms, that the supposedly calm blanket of the inner of the earth's , the plasmasphere almost completely erodes into outer space. ***************************** My words..... Thus letting cosmic rays.,...etc free access to the earth's surface... ******************************* Well...I'll look for some more coherent references....

[Ernest_at_the_Beach]

This seems closer to the Popular Science article:

Inner Magnetospheric Shielding, Penetration Electric Field, and the Plasmasphere

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Conclusions 

The plasmasphere is the torus of cold, dense, co-rotating plasma surrounding the Earth out to 3-5 RE, and  is populated by ionospheric outflow. 

The plasmapause is the outer boundary of the plasmasphere, but does not need to coincide with the instantaneous boundary between convection and co-rotation (the “last closed equipotential” or LCE), because the time scale for plasmaspheric response is slower than the time scale of convection variations. 

Plasmaspheric tails form during periods of high activity (Kp high, or Dst low), and extend all the way down to the ionosphere.  (They can therefore affect Earth communications.) 

The inner magnetosphere tries to shield itself from the convection E-fields, but the buildup of an effective shielding layer takes time.  If the convection strength varies faster than the shielding time scale (somewhere between 15 minutes and an hour), E-fields can penetrate past the shielding layer, and into the inner magnetosphere. 

Penetration E-fields can affect both plasmaspheric populations (forming meso-scale structure such as tails, shoulders and/or bite-outs), and ring current distributions.