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1.
本文基于海洋大气近地层相似理论和一维Kolmogorov 谱函数, 建立考虑各向同性和各向异性湍流效应的蒸发波导模型, 并基于相对误差理论, 将数值模拟的大气修正折射率与根据试验采集数据计算得到的修正折射率进行对比分析。研究结果表明: 湍流效应对蒸发波导模型的预测结果有影响, 且考虑各向异性湍流效应的蒸发波导模型预测精度更高。因此在构建蒸发波导模型时, 需要考虑各向异性湍流对大气折射率的扰动影响, 才能得到更准确的大气修正折射率廓线。通过引入各向异性大气湍流理论, 能够有效提升蒸发波导模型的适用性, 为后续反演大气波导提供较好的模型基础。  相似文献   

2.
海洋飞沫方案改进对台风“威马逊”强度预报的影响   总被引:1,自引:0,他引:1  
本文采用分粒径段组合方式改进海气耦合模式海洋飞沫方案,并利用耦合模式对1409号台风"威马逊"进行数值模拟,分析了海洋飞沫方案改进对台风结构、强度以及海气动量通量、热量通量模拟结果的影响。结果显示,耦合模式中海洋飞沫方案可通过改变海表面粗糙度影响海气动量与热量通量;海洋飞沫还可以通过沫滴向大气输送感热和水汽而直接影响海气热通量,进一步影响台风的强度。模拟结果显示改进后海洋飞沫方案的台风强度更接近观测。改进海洋飞沫方案后粗糙度的计算结果小于原始方案,相应地海气热通量以及下垫面耗散作用也弱于后者,海表面风场是海气热交换与下垫面耗散共同作用的结果。  相似文献   

3.
The influence that cool skin has on the energy exchange between the atmosphere and the ocean is investigated in this work. For this purpose, a series of numerical experiments with the use of the one-dimensional LAKE model of a water body were performed. Three types of cold-skin parameterization were used in this model. The data of in situ measurements in the coastal zone of the Black Sea, in the Arctic Ocean, and over Lake Sparkling served as the boundary and initial conditions. It has been established from the results of experiments that the LAKE model with the incorporated parameterization of the cool skin successfully reproduces cold-skin characteristics, namely, the difference between the temperature of the cool skin surface and the water temperature below the skin. The results of numerical experiments are within the variability of the results of in situ measurements. It has been shown that the presence of a cool skin reduces the heat losses of a body of water. The numerical experiments showed that the presence of a cool skin can change the thermal regime of a water body and its stratification by changing the heat balance at the surface. This result can be important for the modeling of many processes inside a body of water and at its surface, for example, gas and heat exchange.  相似文献   

4.
A physical and mathematical model of the vertical heat and moisture transfer and the carbon exchange in the soil-vegetation-atmosphere system is proposed that includes the interaction between these processes. The model describes the interception of precipitation by plants and its further evaporation, transpiration, evaporation from a soil surface as well as vertical moisture transfer, photosynthesis, and plant and soil respiration. The model has been verified against data from observations of heat, moisture, and carbon dioxide fluxes at a grassland site (international FIFE experiment, Kansas, United States), in a pine forest (BOREAS, Saskatoon, Canada), and in a broad-leaved mixed forest (FLUXNET measurements in the southeastern United States). Numerical experiments with the models have been conducted to estimate the influence of soil moisture and atmospheric CO2 concentration on transpiration and carbon exchange of the vegetation cover.  相似文献   

5.
On the basis of the contemporary array of oceanographic and hydrometeorological data, we compute the characteristics of variations of the Gulf-Stream transport in 1950–2004. The role played by the low-frequency oscillations of vorticity of the wind field and turbulent heat fluxes in the North Atlantic in the formation of the analyzed variations is estimated. We reveal a significant (on a 5% confidence level) positive linear trend of the monthly average Gulf-Stream transport manifested in the increase in the Gulf-Stream transport by 13 Sv for the investigated period. On the basis of the established estimates, we make a conclusion that about a quarter of the interannual variations of the Gulf-Stream transport is caused by the low-frequency oscillations of vorticity of the wind field in the Subtropical Atlantic. Moreover, the Gulf-Stream transport is delayed relative to the wind oscillations by about 2 yr. An important role in the changes in the Gulf-Stream transport is played by the response of the system of west boundary currents to the quasiperiodic action of turbulent heat fluxes on the surface of the ocean connected with the North-Atlantic Oscillation. The intensification of turbulent heat fluxes in the Northern Subpolar Cyclonic Gyre and their weakening in the north part of the Subtropical Anticyclonic Gyre are accompanied by the intensification of the Gulf Stream observed after 3–5 yr. The anomalies of turbulent heat fluxes of the opposite sign are followed by weakening of the Gulf Stream also after a period of 3–5 yr. We also mention a potentially important role played the Pacific decadal oscillation in maintaining the decadal variations of the intensity of Gulf Stream. The influence of this oscillation on the Gulf-Stream transport is realized both via the changes in the wind field in different phases of oscillations and due to its influence on the heat exchange of the ocean with the atmosphere.  相似文献   

6.
海洋表层气泡运动规律的研究   总被引:2,自引:0,他引:2  
建立了海洋表层气泡运动和半径变化的数学模型,通过计算发现一定深度的气泡存在一个临界半径;在一定初始深度气泡的半径小于临界半径时不能到达水面,随着时间的增长,气泡半径逐渐变小,直至最终溶解;气泡的半径大于临界半径时,气泡随着时间的增长,半径逐渐增大,直至达到水面破碎;气泡的初始深度不同,其临界半径也不同;半径在临界点附近的气泡的存活时间最长.对海洋表层气泡运动规律的研究对了解海洋表层气泡的分布规律有重要意义.  相似文献   

7.
杭州湾内水温在不同时间尺度下均存在变化,这对河口生态等会产生影响。由于昼夜气温变化大,空气和海水的热量交换较为频繁。另外,随着气温的逐日下降,水温也随之降低。为研究日气温变化下杭州湾内的水温变化,建立了三维数学模型,通过考虑水面和空气的热交换通量,复演了日气温变化下湾内水温特征。经过和实测潮流数据比较,本文模型很好地模拟出了杭州湾内大、中和小潮期间水流的变化。在综合考虑太阳辐射、长波辐射和水气感热交换下,模型成功再现了日气温变化下水温的变化过程。研究结果一方面有助于认识强潮河口湾内水温变化特征,另一方面将为研究温度对泥沙运动的影响提供前期基础。  相似文献   

8.
A combined mathematical model has been developed to reproduce space and time variations in the concentrations of multicomponent gas constituents and aerosols in the atmosphere on both regional and urban scales. This model contains blocks of transport of gas constituents and aerosols in the atmosphere with consideration for homogeneous binary nucleation, the kinetic processes of condensation/evaporation and coagulation, chemical processes occurring in both gas and liquid phases, and the processes of mass exchange during the gas-droplet (particle) interaction. A nonhydrostatic model of atmospheric mesoscale processes is used to calculate the fields of meteorological elements and turbulent characteristics. The generation of new-phase particles from precursor gases by the mechanism of homogeneous binary nucleation and their interaction with background aerosol are considered. The results of numerical experiments are compared with the data obtained from field observations of both space and time variations in the concentrations of gas constituents and aerosols and in the ionic content of aerosol particles over the Baikal region under the influence of emissions from powerful industrial sources.  相似文献   

9.
On the basis of well-known solutions, we analyse an internal surge, i.e. a sharp step-like variation of the pycnocline depth in a shallow basin. According to results obtained, in those cases where the pycnocline is situated approximately at mid-depth of the basin, the surge may have the form of a steadily moving non-linear wave (kink) governed by the combined Korteweg-de Vries equation with quadratic and cubic non-linearities. The vertical velocity component in such a wave has the form of a pulse and represents a soliton. Estimates of surge parameters obtained from real hydrologic data are in good agreement with the experimentally measured data.Translated by Vladimir A. Puchkin.  相似文献   

10.
A modelling approach is proposed to evaluate the environmental dynamics of coastal lagoons. The water, heat and salt balances are addressed simultaneously, providing a better estimation of evaporation and water exchanges. Compared to traditional approaches, the model presented accounts for the effects of water salinity, heat storage and net energy advected in the water body. The model was applied daily to the Mar Menor coastal lagoon (SE Spain) from 2003 through 2006. Water exchanges with the Mediterranean Sea were estimated based on the monthly trend of the lagoon salinity and were correlated with monthly averages of wind speed. The mean daily water exchange with the sea was 1.77 hm3 d−1. This exchange accounted for only 1% of the heat losses in the lagoon heat balance, and it is the most important flow in the water balance. The mean annual evaporation flux amounted to 101.3 W m−2 (3.55 mm d−1), while the sensible heat flux amounted to 19.7 W m−2, leading to an annual Bowen ratio on the order of 0.19. To validate the model, daily water temperatures were predicted based on the daily heat balance of the water body and were compared with remote sensing data from water surface standard products.  相似文献   

11.
For a one type of temperature turbulent convection observed in the ocean, i.e., for the two-dimensional roller-type convection, we propose a model intended for the evaluation of the intensity and depth of penetration of convective motions as functions of a given heat flow from the sea surface and the temperature gradient in the thermocline. This model is based on the methods of the theory of turbulent jets and experimental data on the vertical distribution of temperature in the course of convection. The comparison of the calculated dimensionless values of the depth of penetration of the thermocline in autumn and winter shows a good qualitative agreement with the data ofin situ measurements. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

12.
The influence of high vertical velocity gradients in the Black Sea Rim Current on the intensity of the vertical turbulent exchange is demonstrated on the basis of numerical modeling based on CTD data. The vertical turbulent exchange is confirmed by the anomalous distribution of the hydrochemical parameters in the redox layer. A system of equations for the kinetic energy of the turbulence and dissipation rate (k-? model) is used for the calculation of the coefficient of the vertical turbulent viscosity (diffusivity).  相似文献   

13.
孙涛  何林帮 《海洋学报》2023,45(2):130-138
在多波束测深中,温盐深剖面数据的准确性对测量精度起到非常重要的作用,而在实际测量中,温盐深误差又不可避免地存在。为了分析温盐深变化对波束脚印坐标的影响规律并将其影响值量化,本文在声速剖面间接测量数据的基础上,选择精度较高、适应性较强的声速经验公式推导其误差公式,计算温盐深变化所引起的声速误差值,并且在常梯度声线跟踪模型的基础上推导出声波旅行轨迹的水平位移和垂直位移误差公式,然后结合声速剖面计算出声速误差对波束脚印坐标的影响程度。实验结果表明,温度变化对声速的影响最大,盐度和深度依序次之;温度、盐度、深度3个参量的变化引起波束脚印Z坐标的变化量均大于X、Y坐标,最高可达变化前深度的0.6%。温度和盐度的变化引起的三轴坐标值变化量随入射角的增大而减小,而深度变化引起的三轴坐标值变化量几乎不随入射角的变化而变化。本文研究结果可为温盐深误差对多波束测深精度评估工作提供借鉴作用。  相似文献   

14.
We demonstrate the importance of investigation of the behavior of methane as a source of energy and an element of the Black-Sea ecosystem affecting the global behavior of the climate. We describe the genesis of methane and the processes of its aerobic and anaerobic oxidation. An especially important biogeochemical and ecological role is played by the anaerobic oxidation of methane guaranteeing the formation of its effective sink inside the anaerobic zone and preventing its penetration into the atmosphere as a greenhouse gas. On the basis of the analysis of the experimental data available from the literature, we also discuss the principal regularities of the distribution of concentration of methane and its flows. It is shown that the formation of methane hydrates at the bottom in the abyssal part of the Black Sea and the events of jet gas release on the periphery of the basin can be regarded as the components of a single global process of gas release from the bottom of the Black Sea. We present estimates of the components of methane budget in the Black Sea. The results of simulation of the dynamics of methane bubbles and the processes of their gas exchange with the medium are analyzed. The data of hydroacoustic measurements are used to evaluate the distribution of methane bubbles in sizes and the mass transfer of methane through the ocean–atmosphere interface. Finally, we consider the methods of mathematical simulation of the distribution of methane in the ecosystem of the Black Sea. Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 40–56, September–October, 2008.  相似文献   

15.
In July 2007, integrated studies of the Amur Estuary and the adjacent aquatic areas were performed on board R/V Professor Gagarinskii within the project of the Amur River basin exploration. On the basis of the data obtained during the cruise, the carbonate system of the Amur Estuary in the summer period was considered. It was shown that the distribution of the carbonate parameters in the Amur Estuary and the adjacent aquatic areas points to the high intensity of the bio-geochemical processes of production and mineralization of organic matter. It was found that the organic matter destruction is prevailing over the photosynthesis in the riverine part of the estuary. This aquatic area is a source of carbon dioxide for the atmosphere and rates as a heterotrophic basin. On the contrary, the surface waters at the outer boundaries of the estuary (the Gulf of Sakhalin and the Tatar Strait) act as a sink of the atmospheric carbon dioxide, which is caused by the intense photosynthesis in this area. This part of the estuary is treated as an autotrophic basin.  相似文献   

16.
南沙海域万安盆地地质构造特征   总被引:1,自引:3,他引:1  
利用在南沙海域万安盆地所采集的地震、重磁资料及钻井、地质资料,对该盆地的地震反向特征,沉积特征、区域地质、构造特征及构造发展史进行了的简要的论述,本文以该区Tg深度资料为基础,并利用CCOP年刊发表的新生代基底深度资料,初步圈定了万安盆地的边界,并对盆地二级构造单元进行了划分,将盆地划分为5坳3隆、坳隆相间的构造格局。  相似文献   

17.
The main factors controlling the ground thermal regime characteristic of cold regions are analyzed with the use of a one-dimensional model of heat and moisture transport in the soil and its interaction with the atmosphere. The influence of these factors on the state of permafrost and the present-day climate as a whole is investigated on the basis of numerical experiments with a global model of general atmospheric circulation. It is shown that a decrease in the heat conductivity coefficient of the upper soil level, which can be interpreted as a layer of nondecomposed litter and moss, considerably increases the area occupied by permafrost. The introduction of the dependence of the heat conductivity coefficient on the phase state of water in the ground also increases the area occupied by permafrost and decreases the depth of the layer of its seasonal thawing in this territory. It is also established that the larger the relative amount of water which can be contained in the ground in a supercooled state is, the higher its temperature is, the lager the active layer depth is, and the smaller the area occupied by perennially frozen rocks is.  相似文献   

18.
The WOCE-era 3-D Pacific Ocean circulation and heat budget   总被引:2,自引:0,他引:2  
To address questions concerning the intensity and spatial structure of the three-dimensional circulation within the Pacific Ocean and the associated advective and diffusive property flux divergences, data from approximately 3000 high-quality hydrographic stations collected on 40 zonal and meridional cruises have been merged into a physically consistent model. The majority of the stations were occupied as part of the World Ocean Circulation Experiment (WOCE), which took place in the 1990s. These data are supplemented by a few pre-WOCE surveys of similar quality, and time-averaged direct-velocity and historical hydrographic measurements about the equator.An inverse box model formalism is employed to estimate the absolute along-isopycnal velocity field, the magnitude and spatial distribution of the associated diapycnal flow and the corresponding diapycnal advective and diffusive property flux divergences. The resulting large-scale WOCE Pacific circulation can be described as two shallow overturning cells at mid- to low latitudes, one in each hemisphere, and a single deep cell which brings abyssal waters from the Southern Ocean into the Pacific where they upwell across isopycnals and are returned south as deep waters. Upwelling is seen to occur throughout most of the basin with generally larger dianeutral transport and greater mixing occurring at depth. The derived pattern of ocean heat transport divergence is compared to published results based on air–sea flux estimates. The synthesis suggests a strongly east/west oriented pattern of air–sea heat flux with heat loss to the atmosphere throughout most of the western basins, and a gain of heat throughout the tropics extending poleward through the eastern basins. The calculated meridional heat transport agrees well with previous hydrographic estimates. Consistent with many of the climatologies at a variety of latitudes as well, our meridional heat transport estimates tend toward lower values in both hemispheres.  相似文献   

19.
孙丹译  李爽 《海洋与湖沼》2020,51(6):1310-1319
大气和海洋是影响地球气候系统的两个重要因素,它们之间的相互作用是海洋和大气研究的重要课题,海气耦合模式则是研究海气相互作用的重要工具,而海气耦合模式重点考虑的参数是海气通量。针对传统的大尺度海气耦合模式缺少湍流尺度分析的问题,本文使用并行大涡模拟海气耦合模式(The Parallelized Large-Eddy Simulation Model,PALM),在小尺度上探究风速对海气通量及湍流动能收支(Turbulence Kinetic Energy Budget,TKE Budget)的影响,设置了5、10和15m/s三种地转风速度对大气边界层(Atmospheric Boundary Layer,ABL)和海洋混合层(Oceanic Mixed Layer,OML)进行海气耦合模拟。研究表明:海气通量的分布与风速大小密切相关,风速越大,净热通量和浮力通量相对越大,由于温度上升导致海水蒸发加剧,使得大气的淡水通量增大;海洋湍流动能收支各项在近海面处受风速影响较大,且随着深度加深而逐渐减弱。本研究初步展示了小尺度海气耦合模式在海气通量研究中的应用,对进行小尺度海气相互作用研究具有一定的意义。  相似文献   

20.
针对海表高度计资料的同化,考查了背景误差协方差矩阵的不同求逆方案对同化效果的影响。所使用的求逆方案包括避免求逆的经验正交函数方案(EOF/EOF_var)、递归滤波方案(RF/RF_var)以及采用初等变换法直接求逆的方案(Inv)。基于上述方案开展了热带太平洋地区2002年1-7月的TOPEX/Poseidon高度计资料同化试验,并利用SODA再分析资料和TAO观测资料评估了各方案对温度场的同化效果,主要得到如下结果:与SODA相比较,Inv方案对模式温度场改进甚微,其余四种方案在100~300 m深度之间对温度场改进较多,在其它深度范围内则改进较少;与TAO观测相比较,EOF_var、RF_var方案对模式温度场改进最多,EOF和RF方案次之,Inv方案则对温度场改进甚少。  相似文献   

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