Dredging for edible cockles (Cerastoderma edule) on intertidal flats: short-term consequences of fisher patch-choice decisions for target and non-target benthic fauna     

Kraan  Casper; Piersma  Theunis; Dekinga  Anne; Koolhaas  Anita; van der Meer  Jaap 《ICES Journal of Marine Science》2007,64(9):1735-1742

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The roughness of wind waves   总被引：12，自引：0，他引：12  

N. Maat  C. Kraan  W. A. Oost 《Boundary-Layer Meteorology》1991,54(1-2):89-103

In this paper, a new dynamic roughness equation for airflow over wind waves is proposed, based on relationships of dimensionless parameters and the 1986 HEXMAX field data. The equation can be considered as a modification of the Charnock formula. The data are also compared with the parameterizations of Toba and Koga, and of Hsu, and the consequences of the new equation for aerodynamic drag are discussed. In the new equation, the drag coefficient is expressed as a function of both wind speed and wave age c _p/u_*. This testifies to the strong wave-age dependence of the drag, found in several experimental studies. It is also in good agreement with results of a theoretical model of the airflow-seawave interaction, proposed by Janssen (1989).Also: Dept. of Applied Physics, Techn. Univ. Delft, the Netherlands.  相似文献   

Sea surface wind stress and drag coefficients: The hexos results   总被引：17，自引：1，他引：17  

Stuart D. Smith  Robert J. Anderson  Wiebe A. Oost  C. Kraan  Nico Maat  Janice De Cosmo  Kristina B. Katsaros  Kenneth L. Davidson  Karl Bumke  Lutz Hasse  Helen M. Chadwick 《Boundary-Layer Meteorology》1992,60(1-2):109-142

Turbulent fluxes have been measured in the atmospheric surface layer from a boom extending upwind from the Dutch offshore research platform Meetpost Noordwijk (MPN) during HEXMAX (Humidity Exchange over the Sea Main Experiment) in October–November, 1986. We started out to study eddy flux of water vapour, but discrepancies among simultaneous measurements made with three different anemometers led us to develop methods to correct eddy correlation measurements of wind stress for flow distortion by nearby objects. We then found excellent agreement among the corrected wind stress data sets from the three anemometers on the MPN boom and with eddy correlation measurements from a mast on a tripod. Inertial-dissipation techniques gave reliable estimates of wind stress from turbulence spectra, both at MPN and at a nearby ship. The data cover a range of wave ages and the results yield new insights into the variation of sea surface wind stress with sea state; two alternative formulas are given for the nondimensional surface roughness as a function of wave age.  相似文献