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J.A. Battjes 《Coastal Engineering》1984,8(2):141-160
A review is given of methods for the synthesis of climate statistics for breakwater design, particularly with respect to the waves. Sources considered are wind data and wave data, both visual and instrumental. The need to extract information from all potential sources is stressed. Some methods to be used for this purpose are mentioned, and an indication is given of results which have been obtained. Uncertainties inherent in estimation of climate parameters are discussed, particularly for extreme events. 相似文献
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Analyses are presented of field measurements of spectral transfer functions between surface elevation and subsurface three-dimensional particle velocity in wind-generated waves, in conditions ranging from young seas to old swells. The results are in agreement with the linear theory predictions to within the measurement error margin, which is estimated to be ± 5% for the gain functions and ± 4° in phase as far as the possible systemic errors are concerned. No correlation is found of the degree of agreement between measurements and linear theory with wave age or wave sleepness. 相似文献
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This paper revisits the derivation of the parametric surf zone model proposed by Baldock et al. [Baldock, T. E., Holmes, P., Bunker, S. & Van Weert, P. 1998 Cross-shore hydrodynamics within an unsaturated surf zone. Coast. Eng. 34, 173–196.]. We show that a consistent use of the proposed Rayleigh distribution for surf zone wave heights results in modification of the expressions for the bulk dissipation rate and enhanced dissipation levels on steep beaches and over-saturated surf zone conditions. As a consequence, the modification proposed herein renders the model robust even on steep beaches where it could otherwise develop a shoreline singularity. 相似文献
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The land cover and carbon cycle consequences of large-scale utilizations of biomass as an energy source 总被引：1，自引：0，他引：1
Rik Leemans André van Amstel Coos Battjes Eric Kreileman Sander Toet 《Global Environmental Change》1996,6(4):335-357
The use of modern biomass for energy generation has been considered in many studies as a possible measure for reducing or stabilizing global carbon dioxide (CO2) emissions. In this paper we assess the impacts of large-scale global utilization of biomass on regional and grid scale land cover, greenhouse gas emissions, and carbon cycle. We have implemented in the global environmental change model IMAGE the LESS biomass intensive scenario, which was developed for the Second Assessment Report of IPCC. This scenario illustrates the potential for reducing energy related emission by different sets of fuel mixes and a higher energy efficiency. Our analysis especially covers different consequences involved with such modern biomass scenarios. We emphasize influences of CO2 concentrations and climate change on biomass crop yield, land use, competition between food and biomass crops, and the different interregional trade patterns for modern biomass based energy. Our simulations show that the original LESS scenario is rather optimistic on the land requirements for large-scale biomass plantations. Our simulations show that 797 Mha is required while the original LESS scenario is based on 550 Mha. Such expansion of agricultural land will influence deforestation patterns and have significant consequenses for environmental issues, such as biodiversity. Altering modern biomass requirements and the locations where they are grown in the scenario shows that the outcome is sensitive for regional emissions and feedbacks in the C cycle and that competition between food and modern biomass can be significant. We conclude that the cultivation of large quantities of modern biomass is feasible, but that its effectiveness to reduce emissions of greenhouse gases has to be evaluated in combination with many other environmental land use and socio-economic factors. 相似文献
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Jurjen A. Battjes 《Coastal Engineering》1982,6(1):47-57
A case study is presented of the effects of tidal currents on the wave heights in a tidal entrance, viz. the Oosterschelde estuary in the Netherlands. Observations of the variation of wave height with tidal elevation during a tidal cycle show a hysteresis. In order to investigate this phenomenon, calculations have been made of wave height changes due to refraction by non-uniform depths and currents, including the occurrence of wave breaking on the shoals in the estuary delta. The calculated wave height variation with tide elevation is found to have a current-induced hysteresis similar to the observed one. 相似文献
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