Geophysical flows are commonly studied using shallow water equations under β-plane approximation, which support zonally propagating equatorially trapped waves. There is a lack of comprehensive understanding of effects of shear on these waves. Additionally, the suitability of β-plane approximation has not been systematically addressed.
In this talk, I will address the effects of mean shear on waves and limitations of β-plane by contrasting the eigenfrequency and equatorial trapping of modes between equatorial easterly and westerly profiles.
Next, I will discuss the non-normal growth of the system. In contrast to β-plane, the non-normality of the governing operator on the sphere enables the system to exhibit significant non-normal growth. I will discuss the growth and structure of optimal initial conditions responsible for growth in different configurations on the sphere. Finally, I will briefly discuss some features of the non linear evolution of these states.
Zoom link: https://icts-res-in.zoom.us/j/93662524822?pwd=OXnnJgl13w0VNlJAfyeZWxOnKGL6aQ.1
Meeting ID: 936 6252 4822
Passcode: 202030