Instabilities and nonlinear processes in geophysics and astrophysics

A review of some nonlinear effects related to plasma instabilities is presented. Discussions are included on (1) quasilinear diffusion, in which a comparison between the effects of electromagnetic and electrostatic turbulence is given; (2) anomalous resistivity, in which a general derivation of the anomalous resistivity is presented and compared with some concrete examples; (3) wave‐wave and wave‐particle interactions, in which a general theory of parametric instabilities and quenching is presented together with the effects of the nonlinear Landau damping on stabilization of linear instabilities; and (4) modulational instability, in which a general derivation of the instability conditions and the consequence of the instability are discussed.