A theoretical estimate of the pole-equator temperature difference and a possible origin of the near-surface shear layer

TL;DR

This paper provides a theoretical estimate of the pole-equator temperature difference in the Sun and explores its implications for the origin of the near-surface shear layer, linking thermal wind balance to observed solar rotation features.

Contribution

It introduces a method to estimate the pole-equator temperature difference using thermal wind balance and relates it to the near-surface shear layer in the Sun.

Findings

Estimated pole-equator temperature difference using thermal wind balance.

Identified a layer of strong differential rotation consistent with observations.

Broad agreement between derived characteristics and observational data.

Abstract

Convective motions in the deep layers of the solar convection zone are affected by rotation, making the convective heat transport latitude-dependent, but this is not the case in the top layers near the surface. We use the thermal wind balance condition in the deeper layers to estimate the pole-equator temperature difference. Surface observations of this temperature difference can be used for estimating the depth of the near-surface layer within which convection is not affected by rotation. If we require that the thermal wind balance holds in this layer also, then we have to conclude that this must be a layer of strong differential rotation and its characteristics which we derive are in broad agreement with the observational data of the near-surface shear layer.