Abstract

Recently, various kinds of inertial modes have been detected on the Sun. The restoring force of these inertial modes is the Coriolis force, and thus they have completely different mode properties from acoustic (p) modes. It is expected that the observations of solar inertial modes can potentially be used as an alternative tool to probe the interior of the Sun, especially to constrain some unknown parameters (such as turbulent viscosity and superadiabaticity) that p-modes are insensitive to. In this talk, we use both linear and fully-nonlinear models of the solar convection zone to study the properties of solar inertial modes. We report a discovery of mixed modes between the equatorial Rossby modes and columnar convective (thermal Rossby) modes. The observed amplitudes of the equatorial Rossby modes can be explained by stochastic excitation due to turbulent convection. We also find that the observations of the high-latitude modes can only be reproduced when the latitudinal entropy gradient exists. This result is regarded as an observational evidence of the thermal wind balance in the Sun’s convection zone. Possible effects of the magnetic field will also be discussed.