| 摘要: |
| 基于高分辨率CFSR（climate forecast system reanalysis）风场资料、气候态海洋混合层厚度资料和卫星高度计海面高度异常资料，本文估计了大气风场向全球海洋混合层的近惯性能通量和近惯性能量输入功率，并探究了混合层厚度、风场时间分辨率、经验衰减系数和中尺度涡旋涡度对近惯性能通量和能量输入功率的影响。浮标实测风场和流速表明，本文所用的风场和阻尼平板模型可用于估计风场向全球海洋的近惯性能通量。本文计算得到的大气向全球海洋输入近惯性能量的功率为0.56TW（1TW=1012W），其中北半球贡献0.22TW，南半球贡献0.34TW。在时间上，风场的近惯性能通量呈现各个半球冬季最强、夏季最弱的特征，这和西风带风场的季节变化有关。在空间上，近惯性能通量的高值海域为南、北半球西风带海洋，尤其是南大洋。混合层厚度和风场空间不均匀性使得西风带近惯性能通量呈现纬向变化，即海盆西部强于海盆东部。风场时间分辨率对近惯性能通量的估计至关重要，低时间分辨率风场对近惯性能通量的低估达到13%—30%。阻尼平板模型中的经验衰减系数对近惯性能通量估计的影响不超过5%。中尺度涡旋涡度仅改变近惯性能通量的空间分布，而对全球近惯性能量输入功率的影响可以忽略。 |
| 关键词: 近惯性能通量 CFSR风场 阻尼平板模型 混合层厚度 经验衰减系数 中尺度涡旋 |
| DOI：10.11693/hyhz20200100018 |
| 分类号:P731 |
| 基金项目:国家自然科学基金青年科学基金项目，41706017号 |
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| WIND-GENERATED NEAR-INERTIAL ENERGY FLUX TO THE OCEANS——THE SPATIAL-TEMPORAL VARIATIONS AND IMPACT FACTORS |
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YANG Bing1,2,3,4,5, HOU Yi-Jun1,2,3,4,5
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1.Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;2.CAS Key Laboratory of Ocean Circulation and Waves, Chinese Academy of Sciences, Qingdao 266071, China;3.Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China;4.Laboratory for Ocean and Climate Dynamics, Pilot National Laboratory for Marine Science and Technology(Qingdao), Qingdao 266237, China;5.University of Chinese Academy of Sciences, Beijing 100049, China
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| Abstract: |
| Based on high-resolution CFSR (climate forecast system reanalysis) reanalysis wind, climatological ocean mixed layer depth, and remote sensing sea level anomaly data, the wind-generated near-inertial energy flux to oceans was estimated using the damped slab model, The spatial and temporal characteristics of the energy flux were revealed, and the roles of the mixed layer depth, empirical damping coefficient, and mesoscale eddy vorticity and wind data resolution were examined, Using wind and currents observed by buoy, the CFSR wind and the slab model were confirmed competent to estimate near-inertial energy flux from wind to ocean, Results show that the global wind-generated near-inertial energy input power was 0.56 TW, and the Northern and Southern Hemisphere contributed 0.22 and 0.34 TW, respectively, The global mean near-inertial energy flux was 1.94 mW/m2, of which the Northern and Southern Hemisphere contributed 2.02 and 1.90 mW/m2, respectively, The energy flux reached maximum (minimum) in winter (summer) of each hemisphere, which is related to seasonal variation of wind, The maximum near-inertial energy flux appeared in the mid-latitude westerly belt, especially the Southern Ocean, The spatial inhomogeneity of mixed layer depth and wind led to zonal variation of near-inertial energy flux, i.e., energy flux of western sea basin was stronger than that of the eastern sea basin, The temporal resolution of wind was vital to energy flux estimation, and low temporal resolution wind underestimated the energy flux by 13% to 30%, The empirical damping coefficient of the slab model could cause energy flux change of less than 5% only, The vorticity of mesoscale eddy only resulted in local spatial distribution of energy flux and did not influence the global power input. |
| Key words: near-inertial energy flux CFSR(climate forecast system reanalysis) wind slab model mixed layer depth empirical damping coefficient mesoscale eddy |
