A proper set of models are carefully selected from the literatures to form a wholistic perspective in simulating the wave propagation in evaporation ducts, under a close-to-realistic environment. The split-step Fourier (SSF) propagation algorithm is applied to analyze the propagation properties in evaporation ducts above a rough sea surface, with turbulence in the ducts. The scattering effect o...

It was a huge honour to be asked to give the Marshall Rosenbluth Memorial Lecture. Having never worked on plasma physics, though, I also feel some diffidence! The closest I’ve ever come has been involvement in some peculiar MHD problems that promise an improved understanding of the solar tachocline — more about confining a magnetic field within a plasma than a plasma within a magnetic field. Be...

A weather balloon and its suspended instrument package behave like a pendulum with a moving pivot. This dynamical system is exploited here for the detection of atmospheric turbulence. By adding an accelerometer to the instrument package, the size of the swings induced by atmospheric turbulence can be measured. In test flights, strong turbulence has induced accelerations greater than 5g, where g...

Turbulence in the Earth’s atmosphere is a major obstacle to the detection of planets with coronographic and interferometric methods from the ground. It limits the contrast achievable with high-resolution imaging and the precision of astrometric measurements. Atmospheric turbulence also determines many of the key design parameters of adaptive optics systems and interferometers: site selection, o...

Pilot reports from special turbulence-reporting periods were used t o investigate methods of analyzing and forecasting clear-air turbulence over the United States. Meteorological analyses for the special reporting periods were made objectively by computer using only standard upper air rawinsonde measurements. The wind analyses were built upward from the 400-mb level to the 200-mb level using th...

The temporal covariance function of irradiance-flux fluctua-tions for Gaussian Schell-model (GSM) beams propagating in atmospheric turbulence is theoretically formulated by making use of the method of effective beam parameters. Based on this formulation, new expressions for the root-mean-square (RMS) bandwidth of the irradiance-flux temporal spectrum due to GSM beams passing through atmospheric...

A weather balloon and its suspended instrument package behave like a pendulum with a moving pivot. This dynamical system is exploited here for the detection of atmospheric turbulence. By adding an accelerometer to the instrument package, the size of the swings induced by atmospheric turbulence can be measured. In test flights, strong turbulence has induced accelerations greater than 5g, where g...

Our recent work in which we study the propagation of the general Hermite-sinusoidal-Gaussian laser beams in wireless broadband access telecommunication systems is elaborated in this paper to cover the special case of an off-axis Gaussian beam. We mainly investigate the propagation characteristics in atmospheric turbulence of an off-axis Gaussian beam possessing Gaussian distributed random displ...

Atmospheric convective boundary layer (CBL) entrainment is the downward mixing of free atmospheric air into the CBL as the CBL grows. Primarily, the CBL entrainment is driven by the buoyancy production of turbulence kinetic energy (TKE) due to heating of the lower surface or cooling at the CBL top. The effects of shear-generated turbulence in the CBL are secondary. However, cases of a purely bu...