Rossby number
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THE Hα EMISSION OF NEARBY M DWARFS AND ITS RELATION TO STELLAR ROTATION Open
The high-energy emission from low-mass stars is mediated by the magnetic dynamo. Although the mechanisms by which fully convective stars generate large-scale magnetic fields are not well understood, it is clear that, as for solar-type star…
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Defining coherent vortices objectively from the vorticity Open
ISSN:0022-1120
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Parameterization of Frontal Symmetric Instabilities. I: Theory for Resolved Fronts Open
A parameterization is proposed for the effects of symmetric instability (SI) on a resolved front. The parameterization is dependent on external forcing by surface buoyancy loss and/or down-front winds, which reduce potential vorticity (PV)…
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Seasonality of submesoscale flows in the ocean surface boundary layer Open
A signature of submesoscale flows in the upper ocean is skewness in the distribution of relative vorticity. Expected to result for high Rossby number flows, such skewness has implications for mixing, dissipation, and stratification within …
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On Differential Rotation and Overshooting in Solar-like Stars Open
We seek to characterize how the change of global rotation rate influences the overall dynamics and large-scale flows arising in the convective envelopes of stars covering stellar spectral types from early G to late K. We do so through nume…
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Demarcating Circulation Regimes of Synchronously Rotating Terrestrial Planets within the Habitable Zone Open
We investigate the atmospheric dynamics of terrestrial planets in synchronous rotation within the habitable zone of low-mass stars using the Community Atmosphere Model. The surface temperature contrast between the day and night hemispheres…
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The evolution of surface magnetic fields in young solar-type stars II: the early main sequence (250–650 Myr)★ Open
35 pages
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Strong-field spherical dynamos Open
Numerical models of the geodynamo are usually classified into two categories: dipolar modes, observed when the inertial term is small enough; and multipolar fluctuating dynamos, for stronger forcing. We show that a third dynamo branch corr…
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Approaching a realistic force balance in geodynamo simulations Open
Significance Flow in Earth’s liquid core is expected to be primarily governed by the Coriolis force due to Earth’s rotation, the buoyancy force driving the convection, and the Lorentz force due to the geomagnetic field. A relevant geodynam…
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Turbulent Rotating Rayleigh–Bénard Convection Open
Rotation with thermally induced buoyancy governs many astrophysical and geophysical processes in the atmosphere, ocean, sun, and Earth's liquid-metal outer core. Rotating Rayleigh–Bénard convection (RRBC) is an experimental system that has…
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Reconciling solar and stellar magnetic cycles with nonlinear dynamo simulations Open
Is the Sun a solar-type star? The Sun's activity, including sun-spot activity, varies on an 11-year cycle driven by changes in its magnetic field. Other nearby solar-type stars have their own cycles, but the Sun does not seem to match thei…
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Resolving the Paradox of Oceanic Large-Scale Balance and Small-Scale Mixing Open
A puzzle of oceanic dynamics is the contrast between the observed geostrophic balance, involving gravity, pressure gradient, and Coriolis forces, and the necessary turbulent transport: in the former case, energy flows to large scales, lead…
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The connection between stellar activity cycles and magnetic field topology Open
Zeeman–Doppler imaging (ZDI) has successfully mapped the large-scale magnetic fields of stars over a large range of spectral types, rotation periods and ages. When observed over multiple epochs, some stars show polarity reversals in their …
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The Role of Horizontal Divergence in Submesoscale Frontogenesis Open
Oceanic surface submesoscale currents are characterized by anisotropic fronts and filaments with widths from 100 m to a few kilometers; an O (1) Rossby number; and large magnitudes of lateral buoyancy and velocity gradients, cyclonic vorti…
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The surface processes of the Rossby Centre regional atmospheric climate model (RCA4) Open
This report describes the physical processes as part of the surface scheme in the Rossby Centre Regional Atmospheric Climate Model (RCA4). Or more strictly for the version used for the CORDEX downscalings with RCA4. The most important aspe…
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Scales and dynamics of <span>S</span>ubmesoscale <span>C</span>oherent <span>V</span>ortices formed by deep convection in the northwestern <span>M</span>editerranean <span>S</span>ea Open
Since 2010, an intense effort in the collection of in situ observations has been carried out in the northwestern Mediterranean Sea thanks to gliders, profiling floats, regular cruises, and mooring lines. This integrated observing system en…
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Submesoscale Currents in the Subtropical Upper Ocean Observed by Long-Term High-Resolution Mooring Arrays Open
Although observational efforts have been made to detect submesoscale currents (submesoscales) in regions with deep mixed layers and/or strong mesoscale kinetic energy (KE), there have been no long-term submesoscale observations in subtropi…
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Ocean Modeling on a Mesh With Resolution Following the Local Rossby Radius Open
We discuss the performance of the Finite Element Ocean Model (FESOM) on locally eddy‐resolving global unstructured meshes. In particular, the utility of the mesh design approach whereby mesh horizontal resolution is varied as half the Ross…
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A tale of two eddies: The biophysical characteristics of two contrasting cyclonic eddies in the <span>E</span>ast <span>A</span>ustralian <span>C</span>urrent <span>S</span>ystem Open
Mesoscale cyclonic eddies are known to be highly productive. Less well‐known are the dynamics and productivity of smaller cyclonic eddies, known as frontal eddies, that form on the landward side of western boundary currents. In this study,…
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Subcritical Thermal Convection of Liquid Metals in a Rapidly Rotating Sphere Open
7 pages, 8 figures
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PARAMETRIC STUDY OF THE ROSSBY WAVE INSTABILITY IN A TWO-DIMENSIONAL BAROTROPIC DISK Open
Protoplanetary disks with non-axisymmetric structures have been observed. The Rossby wave instability (RWI) is considered as one of the origins of the non-axisymmetric structures. We perform linear stability analyses of the RWI in barotrop…
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Period spacings of γ Doradus pulsators in the Kepler field: Rossby and gravity modes in 82 stars Open
Rossby modes are the oscillations in a rotating fluid, whose restoring force\nis the Coriolis force. They provide an additional diagnostic to understand the\nrotation of stars, which complicates asteroseismic modelling. We report 82\n$\\ga…
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Isotropization at small scales of rotating helically driven turbulence Open
We present numerical evidence of how three-dimensionalization occurs at small scale in rotating turbulence with Beltrami (ABC) forcing, creating helical flow. The Zeman scale ℓ Ω at which the inertial and eddy turn-over times are equal is …
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Effect of weak fluid inertia upon Jeffery orbits Open
We consider the rotation of small neutrally buoyant axisymmetric particles in a viscous steady shear flow. When inertial effects are negligible the problem exhibits infinitely many periodic solutions, the "Jeffery orbits." We compute how i…
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Stellar activity with LAMOST – II. Chromospheric activity in open clusters Open
We use the LAMOST spectra of member stars in Pleiades, M34, Praesepe, and\nHyades to study how chromospheric activity vary as a function of mass and\nrotation at different age. We measured excess equivalent widths of H$\\alpha$,\nH$\\beta$…
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Modeling Postconvective Submesoscale Coherent Vortices in the Northwestern <span>M</span>editerranean <span>S</span>ea Open
For the first time, the formation of submesoscale coherent vortices (SCVs) during intermediate and deep convection events is documented in a realistic high‐resolution (1 km) numerical simulation of the oceanic circulation in the northweste…
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ZK-Burgers equation for three-dimensional Rossby solitary waves and its solutions as well as chirp effect Open
Two-dimensional Rossby solitary waves propagating in a line have attracted much attention in the past decade, whereas there is few research on three-dimensional Rossby solitary waves. But as is well known, three-dimensional Rossby solitary…
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Domains of pulsational instability of low-frequency modes in rotating upper main sequence stars Open
We determine instability domains on the Hertzsprung-Russel diagram for rotating main sequence stars with masses 2-20 $\mathrm M_\odot$. The effects of the Coriolis force are treated in the framework of the traditional approximation. High-o…
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Surface Chlorophyll Enhancement in Mesoscale Eddies by Submesoscale Spiral Bands Open
Oceanic submesoscale processes (with scales ~1–10 km and approximately days) have been progressively recognized as an important upwelling mechanism to close the upper ocean nutrient budget and sustain the primary production in euphotic lay…
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Submesoscale and Mesoscale Eddies in the Florida Straits: Observations from Satellite Ocean Color Measurements Open
Despite their well‐recognized importance in driving ocean physics and biology, submesoscale (diameter < Rossby radius of deformation) eddies have been extremely difficult to observe due to technical difficulties from both field and remote …