抄録
Perturbations generated by symmetric instability can be characterized, in terms of growing normal modes, by slantwise vertical motion bands similar to those observed in frontal rainbands. Nonmodal growths of symmetric perturbations, characterized also by slantwise vertical motion bands, can be produced by linear combinations of normal modes even before the basic state becomes symmetrically unstable in order to generate growing modes. In this paper, normal modes for nonhydrostatic symmetric perturbations in a vertically bounded domain are revisited and constructed by free modes obtained in unbounded domain. The constructed modes form a complete set in the full-solution space, and thus, can construct any admissible solutions to further explore nonmodal growths of symmetric perturbations in the vertically bounded domain beyond previous studies.
