Geoscience Reference
In-Depth Information
activities, measurements of absorption in D region of the ionosphere and polar cap,
and other ground-based observations provide us with additional information (Burov
et al.
2013
).
For monitoring and study of the space weather the modern geophysics has a
powerful tool such as space stations between the Sun and the Earth, flotilla of
satellites in near-earth orbits, solar radio-telescopes, a network of ground-based
radars and magnetometers. One of the challenges of magnetospheric research is
to know enough about the solar activity and geomagnetic storms to make it possible
for us to forecast the space weather. Much emphasis has been put on studies of
this problem during the last few decades due to the increasing deployment of
radiation- current- and field-sensitive systems in space and complex technological
systems on the Earth. Despite much success in the study of this problem, the space
weather forecasting has not become purely an engineering problem and it remains a
formidable task to be accomplished.
Appendix F: FLR Structure
In Sect.
6.2
we study the FLR theory on the basis of the “MHD box” model.
The plasma dynamics is described by Eqs. (
6.25
)-(
6.30
) where all the perturbed
quantities are assumed to vary as exp
i!t
C
ik
y
y
. Eliminating the plasma
velocity from this set of equations we are thus left with the set
i!E
x
=V
A
D
@
z
ıB
y
ik
y
ıB
z
C
0
J
x
;
(6.112)
i!E
y
=V
A
D
@
z
ıB
x
@
x
ıB
z
0
J
y
;
(6.113)
@
z
E
y
D
i!ıB
x
;
(6.114)
@
z
E
x
D
i!ıB
y
;
(6.115)
@
x
E
y
ik
y
E
x
D
i!ıB
z
:
(6.116)
Eliminating the variations of magnetic fields ıB
x
, ıB
y
, and ıB
z
from Eqs. (
6.112
)-
(
6.116
) we come to the set
@
z
C
k
A
E
x
D
ik
y
@
x
E
y
ik
y
E
x
i
0
!J
x
;
(6.117)
@
x
C
@
z
C
k
A
E
y
D
ik
y
@
x
E
x
i
0
!J
y
;
(6.118)
where k
A
D
!
2
=V
A
. Notice that if k
y
D
0,Eqs.(
6.117
) and (
6.118
) are similar
to Eqs. (
6.31
) and (
6.32
). The boundary conditions at the “MHD box” sides, which
correspond to the northern .
z
D
l
1
/ and the southern ionospheres .
z
D
0/,aregiven
by Eq. (
6.35
)
Using a variable separation method, we seek for the solution of Eqs. (
6.117
)
and (
6.118
) in terms of the series
Search WWH ::
Custom Search