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arXiv · 2607.19730

Solar differential rotation driven by baroclinic forcing

L. S. Menicucci·G. Guerrero·M. Dikpati·R. Hester·J. Zhang·P. K. Smolarkiewicz
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Abstract

A combination of recent observations and numerical simulations has called into question whether Sun's interior is characterized by strong turbulent convection, a problem known as convective conundrum. In light of a possible absence of vigorous convective motions, we examine whether the Sun's differential rotation, previously assumed to be tightly coupled to Reynolds stresses, may instead be sustained by the presence of a background latitudinal entropy gradient in thermal wind balance. By performing global hydrodynamical simulations of a rotating spherical shell representing the bulk of the solar convection zone, we demonstrate that solar-like differential rotation can be generated under a variety of thermal stratifications. This work proposes an alternative scenario for the origin of solar differential rotation that accommodates the previously reported discrepancies.

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L. S. Menicucci, G. Guerrero, M. Dikpati, R. Hester, J. Zhang, P. K. Smolarkiewicz. 2026-07-22. Solar differential rotation driven by baroclinic forcing. https://arxiv.org/abs/2607.19730

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