High-Latitude Electrodynamics - The Earth's Ionosphere: Plasma Physics and Electrodynamics - page 408

Solar wind

Wind

Wall

(a)

3 9 4

2 9

9

1 9

1

6 9 5 9

3

6

4

5

2

(b)

Figure 8.15 (a) Schematic diagram showing how a viscous interaction could drive mag-
netospheric convection, along with a fluid analogy. (Courtesy of D. P. Stern and S. Lantz.)
(b) Time history of convecting flux tubes resulting from a viscous interaction. Here all
the flux tubes are closed and also connect into the southern hemisphere, which is not
shown.

the convection cycle in the magnetosphere for the viscous interaction mechanism
along with an analogous process in fluid dynamics. Convection paths in the mag-
netosphere and ionosphere are shown in Fig. 8.15b for the viscous interaction
driver. In this case there are no merging and reconnection regions but simply
locations at which convection on closed field lines changes direction from sun-
ward to antisunward at point 1 and from antisunward to sunward at point 3.
The sunward convection from 4 to 5 to 6 is identical to that shown in Fig. 8.14,
but the antisunward flow in the magnetosphere now exists on closed field lines
in the equatorial plane, as shown by the arrows connecting 1 to 2 to 3.