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Modeling microclimate environments: A verification study   总被引:3,自引:0,他引:3  
A numerical model is developed for simulating microclimate of plants and bare soil. The model evaluates heat, mass, momentum, and radiative fluxes in the soil-plant-atmosphere system. Its vertical domain may extend throughout the whole Planetary Boundary Layer (PBL). The model requires, either, temporal meteorological data of solar radiation, wind speed, air temperature and humidity measured over the field, or, when applied to the whole PBL, initial values of the latter three at its top. Vegetation parameters (leaf area index, photometric properties, root distribution and density) as well as soil texture, hydraulic and photometric properties are considered. The model was verified with meteorological data taken from two different climatological regions, above a bare soil and two cotton fields.For all case studies, observed and calculated values of air (except for within-canopy) and soil temperatures, wind speed, net radiation, and soil-, latent-, and sensible heat fluxes, agreed well with measurements.  相似文献   
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A numerical mesoscale meteorological model has been applied over the heterogeneous terrain of central Israel in order to study wind energy characteristics of three typical synoptic situations. The supportive nature of this method for observationally oriented wind energy studies has been emphasized. Mesoscale forcing effects on the availability of wind energy and on the exponent, p, in the vertical wind power law are evaluated.  相似文献   
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The use of numerical mesoscale models for the evaluation of wind energy potential over non-homogeneous terrain is outlined, focusing on the following: (i) an overview of modelling investigations of relevance to wind energy; and (ii) a discussion of the optimal implementation of mesoscale models in wind energy studies.  相似文献   
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A numerical mesoscale model has been applied to make a preliminary evaluation of the mesoscale climatic changes due to a deliberate flooding of the Qattara depression in Egypt. Simulation of a typical summer synoptic situation has indicated noticeable effects on the horizontal and vertical wind fields, and for the temperature and moisture patterns.  相似文献   
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A numerical two-dimensional model based on higher-order closure assumptions is developed to simulate the horizontal microclimate distribution over an irrigated field in arid surroundings. The model considers heat, mass, momentum, and radiative fluxes in the soil-plant-atmosphere system. Its vertical domain extends through the whole planetary boundary layer. The model requires temporal solar and atmospheric radiation data, as well as temporal boundary conditions for wind-speed, air temperature, and humidity. These boundary conditions are specified by an auxiliary mesoscale model and are incorporated in the microscale model by a nudging method. Vegetation parameters (canopy height, leaf-angle orientation distribution, leaf-area index, photometric properties, root-density distribution), soil texture, and soil-hydraulic and photometric properties are considered.The model is tested using meteorological data obtained in a drip-irrigated cotton field located in an extremely arid area, where strong fetch effects are expected. Four masts located 50 m before the leading edge of the field and 10, 30, and 100 m inward from the leading edge are used to measure various meteorological parameters and their horizontal and vertical gradients.Calculated values of air and soil temperatures, wind-speed, net radiation and soil, latent, and sensible heat fluxes agreed well with measurements. Large horizontal gradients of air temperature are both observed and measured within the canopy in the first 40 m of the leading edge. Rate of evapotranspiration at both the upwind and the downwind edges of the field are higher by more than 15% of the midfield value. Model calculations show that a stable thermal stratification is maintained above the whole field for 24 h. The aerodynamic and thermal internal boundary layer (IBL) growth is proportional to the square root of the fetch. This is also the observed rate of growth of the thermal IBL over a cool sea surface.  相似文献   
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