Surface inhomogeneities, including boundaries between different types of vegetations and land use patterns, have important effects on the structure of the atmospheric boundary layer. Changes in the surface roughness, temperature and wetness make the planetary boundary layer (PBL) nonhomogeneous and produce substantial horizontal gradients of boundary layer properties. Significant differences in...

Cross correlations of the fluctuating wall-shear stress and the streamwise velocity in the logarithmic region of turbulent boundary layers are reported over 3 orders of magnitude change in Reynolds number. These results are obtained using hot-film and hot-wire anemometry in a wind tunnel facility, and sonic anemometers and a purpose-built wall-shear stress sensor in the near-neutral atmospheric...

A collaborative experimental effort in the western Utah salt flats [7] has enabled us to map coherence in turbulent boundary layers at very high Reynolds numbers [Reτ ≈ O(106)]. It is found that the large-scale coherence recently noted in the logarithmic region of laboratory-scale boundary layers [4] is also present in the very high Reynolds number atmospheric surface layer [5]. Two-point corre...

(ABSTRACT) Wind speed data of multi-heights have been examined to investigate the spatial and temporal characteristics of coherent structures in the near neutral marine atmospheric surface layer. With Taylor's hypothesis, the temporal velocity signals have been transformed to spatial fluctuations and then visualize these spatial velocity fluctuations to identify the coherent structures. It has ...

Lead and its stable isotopes have been analyzed in surface water samples (0-600 m) and trapped pro'fides collected at the Bermuda Atlantic Time Series Station (U.S. Joint Global Ocean Flux Study) in April and November 1989. These results are compared with wet atmospheric lead deposition as determined from precipitation continuously collected in Bermuda since August 1988 as part of the Atmospher...