Geoscience Reference
In-Depth Information
S3-2 REV. 2087 2 May 76
250
200
150
100
50
0
1
4
1
2
0
E-Field & Density Profiles
22
20 Apr. 1985
ALT
02:06 - 02:15 UT
300
5
309 km
L
5
3.45
2
4
D
Invariant latitude (deg.)
200
2
5.3
2
2.3
0
2.0
3.6
2
6
10
6
100
80
60
40
20
0
100
Electric
field
J
IN
amp/m
2
0
10
5
Trough
region
10
3
Electron
density
10
4
2
0.8
2
0.4
0
0.4
0.8
H
1
O
1
D
L-
Shell coordinate
10
8
Ion & Electron Temperatures
Invariant latitude (deg.)
25.3
22.3
0
2.0
3.6
2500
Trough region
2000
Electro
n
temp.
1500
1000
GMT
MLT
ILAT
ALT
LAT
03:08:40
2045
58.6
1465
43.5
00
2043
59.4
1465
44.5
20
2041
60.2
1464
45.5
40
2039
61.0
1463
46.4
00
2037
61.8
1462
47.4
03:10:20
2034
62.6
1460
48.4
No data
Ion temp.
500
2
0.8
2
0.4
0
0.4
0.8
D
L -
Shell coordinate
(b)
(a)
Figure 10.3
(a) Electric field, magnetic field, thermal electron, and energetic electron
data obtained on the S3-2 satellite near the intense poleward electric field for revolution
2087 on May 2, 1976. The transition from H
+
to O
+
(shaded region) is coincident with
the strong electric field. The calculated field-aligned current (
J
IN
) is displayed under the
magnetometer trace with arrows indicating current into (downward arrow) or out of
(upward arrow) the ionosphere. [After Rich et al. (1980). Reproduced with permission
of the American Geophysical Union.] (b) Millstone Hill radar-measured electric field
and electron density profiles at an altitude of 309 km (top) and corresponding electron
and ion temperature profiles (bottom). Both plots use a coordinate system centered at the
maximum in the electric field. [After Providakes et al. (1989). Reproducedwith permission
of the American Geophysical Union.]
(typically found in low-altitude satellite observations, e.g., Gussenhoven et al.,
1983), yielding a poleward electric field. Although these viewpoints must in some
sense be equivalent, most if not all theoretical models use the pressure gradient
approach.
Search WWH ::
Custom Search