摘要
分析浮标漂流速度和表层地转流、风海流结果表明:浮标漂流速度和表层地转流具有良好相关性。针对卫星跟踪漂流浮标运动的准地转性,建立了以海表地转流为主要回归自变量的几种回归模型,用以模拟浮标漂流轨迹,以期对浮标运动特性有进一步的认识。对南海中伴随涡旋运动的2个浮标模拟试验显示,诸多模型中以海表地转流、风海流及背景流为自变量的回归模型模拟浮标漂流轨迹效果较好。利用该回归模型,模拟出南海2个漂流浮标轨迹和真实轨迹距离偏差较小且二者运动趋势基本一致。通过分析回归模拟所得风海流、海表地转流及背景流发现:涡旋中心附近浮标漂移主要受地转流的控制,而涡旋边缘处风海流起到关键性作用,正是这部分贡献使得浮标能够进入(脱离)涡旋。背景流的空间分布决定着浮标漂移的最终去向,特别是背景流方向改变的区域,背景流的存在使得模拟浮标轨迹能够像真实轨迹一样运移。
A dataset of two drifters in South China Sea was analyzed, together with the MSLA, Ekman drift, and mean sea surface height. It was shown that the velocity of the drifters is consistent with the geostrophic current derived from MSLA. Several regression models, with an independent variable of sea surface geostrophic current, were set up to simulate the real trajectories of drifters. Experiments on the two drifters showed that the model, with independent variables of sea surface geostrophic current, Ekman drift, and mean circulation, has the best efficiency of simulating real trajectories. The simulated trajectories match the real trajectories perfectly. By analyzing the simulated velocities, it was shown that:①In the middle of eddies, the drifter was controlled mainly by the sea surface geostrophic current;②In the edge of eddies, the Ekman drift played an important role in driving the drifter into (out of) eddies;③The mean circulation made the drifters flow correctly in some regions.
出处
《地球科学进展》
CAS
CSCD
北大核心
2005年第6期607-617,共11页
Advances in Earth Science
基金
国家自然科学基金项目"南海中尺度过程时空变异特征的遥感研究"(编号:40376004)
"南海夏季越南沿岸上升流及其在区域气候变化中的地位"(编号:40476013)
国家863计划项目"面向全球海洋同化计划的南海区域系统"(编号:2002AA639250)资助.
关键词
漂流浮标轨迹
回归模型
南海
中尺度涡旋
Trajectory of drifter
Regression model
Meso-scale eddy, South China sea.
