Examine the local linear growth rate of collisional Rayleigh-Taylor instability during solar maximum

Abstract

This study is the first attempt to examine the effects of terms in the growth rate formula on the magnitude of growth rate during April 1999 to March 2000 (solar maximum). The estimation of linear growth rate is based on the local linear growth rate of collisional Rayleigh‐Taylor instability (Ossakow et al., 1979). The monthly average values of linear growth rate (γ) and associated terms are calculated from the electron profile of Jicamarca digisonde and the atmospheric quantities of MSISE‐90 model under geomagnetic quiet condition. The result shows that the linear growth rate is an essential factor for the development of equatorial spread F (ESF). Furthermore, during this period, the monthly variation in gradient density scale length is neither correlated nor anticorrelated to that in growth rate. In contrast, the monthly variations in the collision frequency and recombination rate are anticorrelated with that in growth rate during this period. Additionally, the altitude range of γ profile is another important factor for the ESF generation.