Results 211 to 220 of about 592,628 (248)

Boundary-layer turbulence spectra in stable conditions

Boundary-Layer Meteorology, 1977
Simultaneous measurements of horizontal and vertical wind speeds and temperature fluctuations at heights up to 91 m in the stable atmospheric boundary layer are described. The power and cospectral shapes show a low-frequency peak (near the Brunt-Vaisala frequency) separated by a spectral gap from a peak at high frequency due to turbulence.
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Eddy Diffusivity in the Stable Boundary Layer

1991
A model for the vertical eddy diffusivity Kzz in the stable boundary layer is developed using the statistical diffusion theory and the concept of local scaling. The functional form of Kzz for large travel time is in agreement with the relations for Km and KH given by Mizuno et al., (1983) and Sorbj an (1985).
Gervásio A. Degrazia, Osvaldo L. L. Moraes   +1 more
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Toward Parameterization of the Stable Boundary Layer

Journal of Applied Meteorology, 1982
Wangara data is used to examine the depth of the nocturnal boundary layer (NBL) and the height to which surface-linked turbulence extends. It is noted that a linearity of virtual temperature profiles has been found to extend up to a significant portion of the NBL, and then diverge where the wind shear rides over the surface-induced turbulence. A series
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Topographically induced waves within the stable boundary layer

Quarterly Journal of the Royal Meteorological Society, 2003
AbstractResults are presented from numerical simulations of stable boundary‐layer flow over low ridges. Internal gravity waves are seen within the boundary layer when a Froude number based on the wavelength of the ridges and the magnitude of the cross‐ridge velocity component becomes sufficiently small.
A. R. Brown, M. Athanassiadou, N. Wood
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Stable boundary layers

2009
The atmospheric boundary layer (ABL) is the lowest part of the atmosphere that is continuously under the influence of the underlying surfaces through mechanical (roughness and shear) and thermal effects (cooling and warming), and the overlying, more free layers.
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Turbulence, Radiation and fog in Dutch Stable Boundary Layers

Boundary-Layer Meteorology, 1999
The effect of longwave radiation on the structure the clear stable boundary layer (SBL) is examined. Special emphasis is given to radiative cooling near the surface and the top of the boundary layer and its impact on the heat flux profile. Further, the formation, growth and dissipation of fog in the SBL are studied both from observations and from a one-
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Turbulence in the Evolving Stable Boundary Layer

Journal of the Atmospheric Sciences, 1979
Abstract The turbulence structure observed in seven early evening runs of the 1973 Minnesota experiments is presented and discussed. Wind and temperature sensors mounted on a 32 m tower and on the tethering cable of a large balloon spanned the entire depth of the rapidly evolving nocturnal boundary layer.
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Stable Boundary-Layer Modelling: Established Approaches and Beyond

Boundary-Layer Meteorology, 1999
In the light of Large Eddy Simulation and other recent work, this paper discusses methods of stable boundary-layer modelling that are established in numerical weather prediction and potentially relevant to other applications, e.g., to dispersion. It is argued that classical scaling theory is best expressed in terms of the local Richardson numbers.
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SOME RECENT ADVANCES IN MODELING STABLE ATMOSPHERIC BOUNDARY LAYERS

2010
The atmospheric boundary layer (ABL) is the lowest part of the atmosphere that is continuously under the influence of the underlying surfaces through mechanical (roughness and shear) and thermal effects (cooling and warming), and the overlying, more free layers.
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A parameterization of the stable atmospheric boundary layer

Boundary-Layer Meteorology, 1988
Two formulations of the stable atmospheric boundary layer are proposed for use in weather forecasting or climate models. They feature the log-linear profile near the surface, but are free from the associated critical Richardson number. The diffusion coefficients in the Ekman layer are a natural extension of the surface layer.
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