Speaker
Description
Analytical and numerical models of the linear and nonlinear stages of evolution of different types of short scale low frequency waves in the mid-latitude ionosphere will be presented. Density gradients and velocity shears observed in the Earth’s ionosphere are likely to undergo Raleigh-Taylor (RT) or Kelvin-Helmholtz (KH) type instabilities, but typically live longer than expected. Possibility of enhanced ionization due to appearance of supra thermal electrons accelerated by excited wave turbulence will be also presented. Obtained density perturbations in the form of nonlinear vortex structures accompanied by short scale turbulent pulsations can strongly affect propagating high frequency electromagnetic waves used for example for GPS applications or satellite communications. These models will be used to estimate the impact on the propagation characteristics of waves ranging from HF to L band diapason. Related experiments on excitation of low frequency waves during the experimental campaigns at the HAARP and the Arecibo Observatory facilities will be also discussed.
This work was supported by the NRL Base Program DISTRIBUTION STATEMENT A. Approved for public release. Distribution is unlimited.
