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An Active Sun Throughout the Maunder Minimum
Measurements of 10Be concentration in the Dye 3 ice core show that magnetic cycles persisted throughout the Maunder Minimum, although the Sun's overall activity was drastically reduced and sunspots
Sensitivity of stratified turbulence to the buoyancy Reynolds number
Abstract In this article we present direct numerical simulations of stratified flow at resolutions of up to $204{8}^{2} \times 513$ , to explore scalings for the dynamics of stably stratified
Convective and absolute instabilities of fluid flows in finite geometry
Abstract Dynamics of linear and nonlinear waves in driven dissipative systems in finite domains are considered. In many cases (for example, due to rotation) the waves travel preferentially in one
On the instability of magnetohydrodynamic shear flows
We consider the linear stability of an ideal, plane–parallel magnetohydrodynamic shear flow with velocity u = (U(z),0, 0) and magnetic field B = (B(z), 0,0). We show how Howard's semicircle theorem
Direct statistical simulation of out-of-equilibrium jets.
It is shown that, for jets near equilibrium, CE2 is capable of reproducing the jet structure (although some differences remain in the second cumulant), but as the degree of departure from equilibrium is increased (as measured by the zonostrophy parameter), the jets meander more and CE2 becomes less accurate.
Dynamo properties of the turbulent velocity field of a saturated dynamo
In order better to understand how dynamo systems saturate, we study the kinematic dynamo properties of velocity fields that arise from nonlinearly saturated dynamos. The technique is implemented by
Transport and Storage of Magnetic Field by Overshooting Turbulent Compressible Convection
We present the results of a series of numerical experiments that investigate the transport of magnetic —elds by turbulent penetrative compressible convection. We —nd that magnetic —ux is
Modulation and symmetry changes in stellar dynamos
Stellar dynamos are governed by non-linear partial differential equations (PDEs) which admit solutions with dipole, quadrupole or mixed symmetry (i.e. with different parities). These PDEs possess
Pumping of Magnetic Fields by Turbulent Penetrative Convection
A plausible scenario for solar dynamo action is that the large-scale organized toroidal magnetic field is generated by the action of strong radial shear at the base of the solar convection zone,
Relating stellar cycle periods to dynamo calculations
ABSTRA C T Stellar magnetic activity in slowly rotating stars is often cyclic, with the period of the magnetic cycle depending critically on the rotation rate and the convective turnover time of the