相关论文: On Zonal Jets in Oceans

Quasigeostrophic flows are induced by spatial variations in interior potential vorticity and boundary buoyancy. We begin by developing the geostrophic turbulence theory of boundary buoyancy anomalies in a fluid with vanishing potential…

Jets are observed in young stellar objects, X-ray sources, active galactic nuclei (AGN). The mechanisms of jet formation may be divided in regular, acting continuously for a long time, and explosive ones. Continuous mechanisms are related…

The mean zonal flow observed on Jupiter consists of an intricate pattern of jets, or bands of zonal flow moving prograde or retrograde compared to the bulk planetary rotation. The strongest flow is a superrotating (prograde) jet near the…

Context: Astrophysical jets from various sources seem to be stratified, with a fast inner jet and a slower outer jet. As it is likely that the launching mechanism for each component is different, their interface will develop differential…

Planets form in active protoplanetary disks that sustain stellar jets. Momentum loss from the jet system may excite the planets' orbital eccentricity and inclination (Namouni 2005, AJ 130, 280). Evaluating quantitatively the effects of such…

This paper looks at the two-layer ocean model from a wave turbulence perspective. A symmetric form of the two-layer kinetic equation for Rossby waves is derived using canonical variables, allowing the turbulent cascade of energy between the…

Many quasars and active galactic nuclei (AGN) appear in radio, optical, and X-ray maps, as a bright nuclear sources from which emerge single or double long, thin jets. When observed with high angular resolution these jets show structure…

Zonal jets are common in planetary atmospheres. Their character, structure, and seasonal variability depend on the planetary parameters. During solstice on Earth and Mars, there is a strong westerly jet in the winter hemisphere and weak,…

Low-mode baroclinic tides play a major role in ocean dynamics, especially for energy redistribution and deep ocean mixing. These internal waves, generated by tidal flow over submarine topography, can propagate for thousands of kilometres…

The collision of magnetic reconnection jets is studied by means of a three dimensional numerical simulation at kinetic scale, in the presence of a strong guide field. We show that turbulence develops due to the jets collision producing…

A detailed study of the Charney-Hasegawa-Mima model and its extensions is presented. These simple nonlinear partial differential equations suggested for both Rossby waves in the atmosphere and also drift waves in a magnetically-confined…

The precise mechanism that forms jets and large-scale vortices on the giant planets is unknown. An inverse cascade has been suggested. Alternatively, energy may be directly injected by small-scale convection. Our aim is to clarify whether…

Many quasars and active galactic nuclei (AGN) appear in radio, optical, and X-ray maps, as a bright nuclear sources from which emerge single or double long, thin jets (Thomson et al., 1993). When observed with high angular resolution these…

This paper presents a study on wave cancellation in forced jets. Building on recent work on real-time control of forced turbulent jets [1,2], we here assess the effect of jet upstream conditions and nonlinearity on wave-cancellation…

Observations of coronal jets increasingly suggest that local fragmentation and intermittency play an important role in the dynamics of these events. In this work we investigate this fragmentation in high-resolution simulations of jets in…

We propose a unified model for jet formation applicable to active galactic nuclei, young stellar objects, and X-ray binaries. In this model, the binding energy released from the accretion disk is primarily stored as turbulence rather than…

The interaction between planetary waves and an arbitrary zonal flow is studied from a phase-space viewpoint. Using the Wigner distribution, a planetary wave Vlasov equation is derived that includes the contribution of the mean flow to the…

Two three-dimensional magnetohydrodynamical simulations of strongly magnetized conical jets, one with a poloidal and one with a helical magnetic field, have been performed. In the poloidal simulation a significant sheath (wind) of…

Vertically banded zonal jets are frequently observed in weakly or non-rotating stratified turbulence, with the quasi-biennial oscillation in the equatorial stratosphere and the ocean's equatorial deep jets being two examples. Explaining the…

We review progress that has been made to constructa theory for the jet formation and maintenance in planetary atmospheres. The theory is built in the regime where velocityfluctuations around the base jet are very small compared to the…