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A procedure for the dynamic initialization of wind and temperature fields within the atmospheric boundary layer (ABL) is presented. The procedure uses transilient turbulence theory to assess the turbulent fluxes from observed wind and temperature data, which are used to estimate the eddy transfer coefficients, so enabling a local closure ABL model to be integrated forward in time to a new steady state. The method has been applied to initialize kytoon data taken at Kharagpur (22.3° N, 87.2° E) during the MONTBLEX field programme. Results of a case study for 17 June 1990 are discussed. 相似文献
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该文在大气边界层多尺度湍流理论和湍流穿越理论的基础上，建立了大气边界层感热通量的非局地多尺度湍流计算方法，并选用1998年5～8月份第二次青藏高原大气科学试验（TIPEX）的大气边界层综合观测基地昌都站观测资料，分别用感热通量的非局地多尺度湍流计算方法和经典相似理论计算感热通量。对计算结果的对比分析表明，用感热通量的非局地多尺度湍流计算方法能计算出感热通量的逆梯度输送，也能计算出青藏高原近中性层结条件下明显的感热通量。此外，多尺度湍流理论还有待进一步发展完善，提高感热通量的计算精度。 相似文献
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A non-local parameterisation of shear turbulence is proposed, which includes a dimensionless multiplicative constant as the
sole tunable parameter. Analytical and numerical solutions in the case of plane Couette flow exhibit sheared velocity profiles
with logarithmic behaviour near the boundaries, and the classical logarithmic flow profile is reproduced for a semi-infinite
domain. We also prove that the families of analytical solutions obtained are locally unique: if the velocity is a strictly-increasing
function of the distance from the boundary, a small perturbation of the velocity profile must be of the same functional form
as the basic flow. 相似文献
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A coupled photochemical–physical model for the upper ocean carbon monoxide concentration is presented. The coupled model uses a spectral optical model and a number of different mixing parameterizations. It is run using the meteorological forcing conditions measured during a 9-day investigation near Bermuda in the Sargasso Sea in March 1993 in the declining phase of the spring bloom. The baseline runs of the model are successful in simulating measurements made during the campaign, and form the basis of an optimization routine to find better estimates of the production and destruction constants of the photochemical tracer. The optimized values derived in this inverse procedure depend on the mixing parameterization and the assumed dark production rate of carbon monoxide. 相似文献
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Ｓｅｎｓｉｔｉｖｉｔｙ Ｓｔｕｄｙ ｏｆ Ｎｏｎｌｏｃａｌ Ｔｕｒｂｕｌｅｎｃｅ ＣｌｏｓｕｒｅＳｃｈｅｍｅ ｉｎ Ｌｏｃａｌ ＣｉｒｃｕｌａｔｉｏｎＣｈｅｎＭｉｎｇａｎｄＨｏｎｅＺｈｏｎｇｘｉａｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＡｔｍｏｓｐｈｅｒｉｃＰｈ... 相似文献
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A. James Kettle 《Ocean Modelling》2005,8(4):301-336
Seven one-dimensional oceanic boundary layer models are investigated to assess the possible nonlocal transport characteristics of mass and heat in the upper ocean. The dynamical models have been chosen from the diffusion and bulk types currently in use plus two modifications of the transilient type that have been used extensively for atmospheric work by Stull. The models are forced using wind speed and insolation conditions recorded during a 9-day oceanographic cruise near Bermuda in March 1993 during the decline of the spring bloom. The attenuation of sunlight in the upper ocean is calculated using a full spectral model for downwelling irradiance. The vertical heat transport characteristics are reported and compared. A series of spectral diagnostic tests (Green's function analysis, process spectra, and overall mixing lengths) reveal significant differences in the vertical transport characteristics of the models that are not observed in commonly used diagnostics such as sea surface temperature or mixed layer depth. Age spectra (or modal time since last surface contact) are calculated from Green's functions and reveal how a water mass can be cut off from the surface within a short time period. The large differences in the vertical mixing characteristics of the upper ocean boundary layer models have potential implications on the vertical distributions of short-lived chemical tracers and phytoplankton. 相似文献
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