Evidence for a Rayleigh‐Taylor type instability and upwelling of depleted density regions during equatorial spread F

Abstract

Recent rocket probe, barium cloud and radar measurements conducted during equatorial spread F conditions are interpreted in terms of a Rayleigh‐Taylor gravitational instability operating on the bottomside of the F peak. The persistent theoretical problems associated with strong radar echoes typically observed in patch‐like structures at high altitudes are explained in terms of regions of depleted plasma density which bouyantly rise against the gravitational field.