Growth of plasma waves of scales longer than 10km by gradient-drift instability in the E-region of equatorial ionosphere

摘要

In this study, a linear analysis of the Gradient Drift Instability (GDI) applicable for horizontal wavelengths longer than 10 km in the E region is presented. By analytically solving the non-local differential equation for the polarization potential, analytical forms of the dispersion relation and growth rate, hosting new contributions from non-local effects, are obtained. The new growth rate and the amplitude of polarization potential are examined for a wide range of wavelengths that reveal the positive growth of GDI for wavelengths of similar to 25 km. These characteristics raise the possibility of the formation of unstable structures of vertical size similar to 20-30 km in the upper E region, often observed during twilight hours. Published by AIP Publishing.