Generation mechanisms of convectively induced internal gravity waves in a three-dimensional framework

Eun Ho Choi, Hye Yeong Chun

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

The generation mechanisms of convective gravity waves in the stratosphere are investigated in a three-dimensional framework by conducting numerical simulations of four ideal storms under different environmental conditions: one un-sheared and three constant low-level sheared basic-state winds with the depth of the shear layer of 6 km and the surface wind speeds (Us) of 8, 18, and 28 m s-1, using the Advanced Regional Prediction System (ARPS) model. The storms simulated under the un-sheared (Us = 0 m s-1), weakly sheared (Us = 8 and 18ms-1), and strongly sheared (Us = 28ms-1) basicstate winds are classified into single-cell, multicell, and supercell storms, respectively. For each storm, the wave perturbations in a control simulation, including nonlinearity and microphysical processes, are compared with those in quasi-linear dry simulations forced by diabatic forcing and nonlinear forcing that are obtained from the control simulation. The gravity waves generated by the two forcing terms in the quasi-linear dry simulations are out of phase with each other for all of the storms. The gravity waves in the control simulation are represented by a linear sum of the wave perturbations generated by the nonlinear forcing and diabatic forcing. This result is consistent with the results of previous studies in a two-dimensional framework. This implies that both forcing mechanisms are important for generating the convective gravity waves in the three-dimensional framework as well. The characteristics of the three-dimensional gravity waves in the stratosphere were determined by the spectral combination of the forcing terms and the wave-filtering and resonance factor that is determined from the basic-state wind and stability as well as the vertical structure of the forcing.

Original languageEnglish
Pages (from-to)163-177
Number of pages15
JournalAsia-Pacific Journal of Atmospheric Sciences
Volume50
Issue number2
DOIs
Publication statusPublished - 2014 Feb

All Science Journal Classification (ASJC) codes

  • Atmospheric Science

Fingerprint Dive into the research topics of 'Generation mechanisms of convectively induced internal gravity waves in a three-dimensional framework'. Together they form a unique fingerprint.

  • Cite this