Equatorial Plasma Instabilities and Mesospheric Turbulence - The Earth's Ionosphere: Plasma Physics and Electrodynamics - page 134

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Magnetic east distance

from Altair ( km)

Figure 4.3a Simultaneous vertical rocket plasma density profile and backscatter map
made with the Altair radar on the island of Kwajalein. Dots show the rocket trajectory.
[After Rino et al. (1981). Reproduced with permission of the American Geophysical
Union.]

not identical, and it is not possible to declare a universal spectral form with any
certainty (unlike Kolmogorov turbulence: see Section 4.9). We can say that they
are typically of the form k − n with 2 3 and that they break to amuch steeper

form somewhere in the range of 60m. In Fig. 4.5b we contrast horizontal spectra
from AE-E, which has access to longer wavelengths with the four rocket spectra
obtained in the Kwajalein rocket campaign and the distribution of scales detected
by an HF channel probe (see Fig. 4.12). The satellite data do not extend to small
enough scales to detect the steep portion of the spectrum, which is more clearly
evident here than in Fig. 4.5a. Figure 4.5b suggests that the two dimensions in
the plane perpendicular to B are not equivalent. Larger perturbation scales exist
horizontally due to its larger extent, of course. But also at intermediate scales, the
rocket spectra are more intense and have steeper spectra. The two vertical lines

≤ n ≤