Convective instability in a compressible atmosphere

✍ Scribed by Chitre, S. M. (author);Gokhale, M. H. (author)

• Publisher: Kluwer Academic Publishers
• Year: 1973
• Tongue: English
• Weight: 524 KB
• Volume: 30
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00152662

✦ Synopsis

The degree of convective instability as expressed by the growth rate co of linear modes, is calculated for a plane parallel polytropic atmosphere in the presence of radiative damping, without using Boussinesq approximation. A comparison with the results based on the Boussinesq approximation reveals that the use of the Boussinesq approximation leads to an overestimation of the radiative damping. The computation of co as a function of the horizontal wave number yields a wavelength of maximal instability under a variety of conditions. For reasonable choices of physical parameters appropriate to the solar atmosphere, the fastest growing wavelengths turn out to be in the range 600-1200 km, and their e-folding times are in the range 200-2000 s.