海洋对大气加热场的区域性年变化特征   总被引：1，自引：0，他引：1  

全小伟  K.Weikmann 《大气科学》1991,15(6):26-35

本文研究了热带和中纬度一些海表面温度年变化较强的区域中海洋对大气加热场的年度化特征。结果表明海洋向大气提供热通量的强度在冷海区呈年周期性变化,而在暖海区呈半年周期性变化。与潜热的湍流输送及海表面向上的长波辐射通量相比,感热的湍流输送量很小。在暖海区潜热输送总大于长波辐射,并且前者有较强的年变化而后者较弱;在冷海区二者的量级相当,年变化幅度也相当。海表风场和云的变化对海洋对大气加热场年变化的影响非常重要。  相似文献   

Ship-board measurements and estimations of air-sea fluxes in the western tropical pacific during TOGA COARE   总被引：1，自引：0，他引：1  

Xilong Song  Carl A. Friehe  Dunxin Hu 《Boundary-Layer Meteorology》1996,81(3-4):373-397

Direct air-sea flux measurements were made on R/V Kexue #1 at 4 ° S, 156 ° E during the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean-Atmospheric Response Experiment (COARE) Intensive Observation Period (IOP). An array of six accelerometers was used to measure the motion of the anchored ship, and a sonic anemometer and Lyman-α hygrometer were used to measure the turbulent wind vector and specific humidity. The contamination of the turbulent wind components by ship motion was largely removed by an improvement of a procedure due to Shao based on the acceleration signals. The scheme of the wind correction for ship motion is briefly outlined. Results are presented from data for the best wind direction relative to the ship to minimize flow distortion effects. Both the time series and the power spectra of the sonic-measured wind components show swell-induced ship motion contamination, which is largely removed by the accelerometer correction scheme. There was less contamination in the longitudinal wind component than in the vertical and transverse components. The spectral characteristics of the surface-layer turbulence properties are compared with those from previous land and ocean results. Momentum and latent heat fluxes were calculated by eddy correlation and compared to those estimated by the inertial dissipation method and the TOGA COARE bulk formula. The estimations of wind stress determined by eddy correlation are smaller than those from the TOGA COARE bulk formula, especially for higher wind speeds, while those from the bulk formula and inertial dissipation technique are generally in agreement. The estimations of latent heat flux from the three different methods are in reasonable agreement. The effect of the correction for ship motion on latent heat fluxes is not as large as on momentum fluxes.  相似文献   

对热带不稳定海气相互作用模式的改进   总被引：1，自引：1，他引：1  

张人禾  巢纪平 《气象学报》1994,52(3):350-358

对以前提出的热带海气相互作用模式［１］风应力的参数化作了改进。和以前一样，在这个耦合模式中，滤去了大气和海洋中的重力惯性波，只保留了向西传播的Ｒｏｓｓｂｙ波。但经过海气相互作用后，理论分析指出，在耦合模式中存在着快的和慢的两类波动。快波频率的实部、即其相速度是向西传的，并接近于未经海气相互作用时大气中Ｒｏｓｓｂｙ波的频率；而慢波的性质和以前的结果类似，短波部分是向西传的，长波部分向东传，东传波的临界波数随海气相互作用增强向短波部分位移。与以前结果不同的是，除一个慢波不稳定增长外，另一个快波在长波部分也是不稳定增长的。海气相互作用越强，不稳定增长率和不稳定波所出现的波段范围越大。另外，本文的研究结果还指出，高频和低频不稳定波产生的物理条件是不一样的。  相似文献   

海气耦合气候模式的依时解   总被引：2，自引：0，他引：2       下载免费PDF全文

封国林  曹鸿兴 《应用气象学报》1996,7(2):212-220

运用量子力学方法，精确地求出了海气耦合随机-动力模式的依时解。对依时解的分析表明:当气候系统处于基态时，系统的行为呈布朗运动形式，由此从理论上证明了Hassel-mann关于随机气候模式建立的立足点。当系统处于第一激发态时，系统运动呈随时间衰减的形式；在一定条件下则为周期振荡，主周期长度为2.3年。最后将结果用来讨论二氧化碳浓度倍增时的气候影响。  相似文献   

Effects of the air–sea coupling time frequency on the ocean response during Mediterranean intense events     

Cindy Lebeaupin Brossier  Véronique Ducrocq  Hervé Giordani 《Ocean Dynamics》2009,59(4):539-549

The near-sea surface meteorological conditions associated with the Mediterranean heavy precipitation events constitute, on a short time scale, a strong forcing on the ocean mixed layer. This study addresses the question of the optimal time frequency of the atmospheric forcing to drive an ocean model in order to make it able to capture the fine scale ocean mixed layer response to severe meteorological conditions. The coupling time frequency should allow the ocean model to reproduce the formation of internal low-salty boundary layers due to sudden input of intense precipitation, as well as the cooling and deepening of the ocean mixed layer through large latent heat fluxes and stress under the intense low-level jet associated with these events. In this study, the one-dimensional ocean model is driven by 2.4-km atmospheric simulated fields on a case of Mediterranean heavy precipitation, varying the time resolution of the atmospheric forcing. The results show that using a finer temporal resolution than 1 h for the atmospheric forcing is not necessary, but a coarser temporal resolution (3 or 6 h) modifies the event course and intensity perceived by the ocean. Consequently, when using a too coarse temporal resolution forcing, typically 6 h, the ocean model fails to reproduce the ocean mixed layer fine scale response under the heavy rainfall pulses and the strong wind gusts.  相似文献   

海洋飞沫及其对海—气相互作用影响的研究进展   总被引：4，自引：0，他引：4  

赵栋梁 《地球科学进展》2012,27(6):624-632

按照海水滴生成机制和粒径大小,由海浪破碎生成的海洋飞沫分为膜滴、射滴和裂滴三大类,较小的海水滴在大气中滞留时间长,成为云的凝结核,对长期气候变化有重要影响,较大的海水滴参与海—气界面动量和热量交换过程,有利于热带气旋的形成和发展。海洋飞沫的生成与海上风速、海浪、海流和大气稳定度等因素有关,但由于缺乏观测数据,刻画海洋飞沫效应的关键物理量——海洋飞沫生成函数通常用海上风速进行参数化,忽略其他因素的影响,彼此间的差异非常大,给研究海洋飞沫对气候和海—气相互作用的影响造成困难,需要进一步开展海洋飞沫的观测,考虑风速之外的其他因素对海洋飞沫生成函数的作用,改进海洋飞沫热量和动量效应的参数化方案,进而阐明海洋飞沫对气候和海—气相互作用的影响。  相似文献   

亚热带珊瑚礁海域枯水季pCO₂的分布特征及CO₂汇源转换机制-以深圳杨梅坑海域为例          下载免费PDF全文

张卓  杨波  崔洲平  林子燚  谢子强  郑惠娜  廖宝林  肖宝华  朱春华 《海洋科学》2023,47(11):45-56

由于存在极高的初级生产和高效的碳代谢速率, 珊瑚礁海域二氧化碳(CO₂)的汇/源属性仍存有争议。为明晰中国典型珊瑚礁海域CO₂的汇源属性及驱动因素, 作者基于2022年11月(秋季)和2023年2月(冬季)在深圳杨梅坑海域的调查结果并结合室内培养实验所获得的数据, 探究了枯水季节典型亚热带珊瑚礁海水二氧化碳分压(pCO₂)的分布特征及主要控制机制。结果表明, 调查期间pCO₂的变化较大, 其范围为233.3~465.3 μatm。秋季表现为大气CO₂的汇, CO₂吸收通量为1.66±0.41 mmol C/(m²/d);冬季表现为大气CO₂的弱源, 其释放通量为0.36±0.17 mmol C/(m²/d)。调查期间(枯水季)杨梅坑海域受淡水输入的影响较小, 季节性温度影响下的生物过程是驱动pCO₂变化的关键因素, 其贡献pCO₂总变化量的73.6%(表层)和66.5%(底层)。其中, 浮游植物光合作用的季节差异是导致海水CO₂汇源转变的主要成因, 而微生物呼吸作用的影响甚微。相比较, 物理过程(CO₂海-气交换、温度和盐度变化)对pCO₂的影响相对较小, 其作用结果远低于生物过程。此外, 珊瑚的代谢活动对杨梅坑局部海域pCO₂分布产生一定影响, 造成礁区pCO₂值高于非礁区。因此, 海气CO₂通量估算中不能忽视局部海域珊瑚代谢作用的影响。  相似文献   

A Lagrangian biogeochemical study of an eddy in the Northeast Atlantic     

T.D. Jickells  P.S. Liss  S. Turner  J. Read  L.M. Cardenas  F. Carse  M. Hamren-Larssen  M. Steinke  A. Thompson  S.D. Archer  C.S. Law  P.D. Nightingale  C.E. Widdicombe  L.C. Gilpin  G. Savidge  P. Hadziabdic  R. Upstill-Goddard  R. Simó  A. Allen 《Progress in Oceanography》2008,76(3):366-398

We report the results of an experiment in the Northeast Atlantic in which sulphur hexafluoride (SF₆) was released within an eddy and the behaviour of trace gases, nutrients and productivity followed within a Lagrangian framework over a period of 24 days. Measurements were also made in the air above the eddy in order to estimate air-sea exchange rates for some components. The physical, biological and biogeochemical properties of the eddy resemble those of other eddies studied in this area, suggesting that the results we report may be applicable beyond the specific eddy studied. During a period of low wind speed at the start of the experiment, we are able to quantitatively describe and balance the nutrient and carbon budgets for the eddy. We also report concentrations of various trace gases in the region which are similar to those observed in other studies and we estimate exchange rates for several trace gases. We show that the importance of gas exchange over other loss terms varies with time and also varies for the different gases. We show that the various trace gases considered (CO₂, dimethyl sulphide (DMS), N₂O, CH₄, non-methane-hydrocarbons, methyl bromide, methyl iodide and volatile selenium species) are all influenced by physical and biological processes, but the overall distribution and temporal variability of individual gases are different to one another. A storm disrupted the stratification in the eddy during the experiment, resulting in enhanced nutrient supply to surface waters, enhanced gas exchange rates and a change in plankton community, which we quantify, although overall productivity was little changed. Emphasis is placed on the regularity of storms in the temperate ocean and the importance of these stochastic processes in such systems.  相似文献   

南亚地区季风与邻近海域海温相互影响的初步研究   总被引：1，自引：1，他引：1  

刘莉红  郑祖光  夏友龙  吴洪 《气象学报》2004,62(2):180-188

文中利用简化的海 气耦合模式及低谱方法和多平衡态理论 ,讨论了南亚地区冬夏季风与邻近海域海温季节变化之间的相互影响。结果表明 :(1)冬季风较强时 ,冬季海温较低 ,翌年夏季海温也较低 ;反之亦然。夏季风较强时 ,夏季海温较高 ;反之亦然。夏季风强弱对冬季海温的影响不明显。 (2 )海 气相互作用使南亚冬季风和夏季风都加强。海温经向梯度使冬季风加强 ,而夏季风减弱。  相似文献   

南海夏季风爆发前后海-气界面热交换特征   总被引：20，自引：1，他引：20  

蒋国荣  何金海  王东晓  张韧  阎俊岳  姚华栋 《气象学报》2004,62(2):189-199

文中利用 2 0 0 0与 2 0 0 2年二次南海海 气通量观测资料和同期西沙站资料 ,研究了南海夏季风爆发前后海洋表面热收支变化特征。研究表明 :南海夏季风爆发前后 ,影响海面热收支变化的主要分量是净短波辐射通量和潜热通量 ,在季风爆发前后不同阶段 ,二个分量的变化有不同表现形式 ,但不论二者如何变化 ,季风爆发与活跃期 ,海面热收入减小或为净支出 ;季风爆发前及中断期间 ,海面热收入逐渐增加 ;由于大的热惯性 ,海温变化落后于海面热收支的变化 ,海温的这种滞后效应通过影响潜热通量调节海面热收支的变化 ,又反过来影响自身的变化 ,形成短期振荡过程 ,这种振荡过程与季风的活跃、中断过程相对应。  相似文献