Measurements of turbulent vertical kinetic energy in the Ocean mixed layer from Lagrangian floats
Measurements of turbulent vertical kinetic energy in the Ocean mixed layer from Lagrangian floats
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拉格朗日浮标测量海洋混合层湍流垂直动能
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
E. D’Asaro
中科院分区：
文献类型：
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作者：
R. Tseng;E. D’Asaro
D 'Asaro在以前的工作中，在风强迫混合层中使用接近中性浮力的拉格朗日浮子，发现^w2 &5，其中^w2 &5是均方垂直速度，u * 是摩擦速度，使用体积公式从船上气象测量中估计2 Au *。A（z）5^ w 2 &（z）/在2 u * 内的深度剖面显示，混合层中A（z）的最大值约为2，这是单独由壁应力驱动的固体壁湍流边界层中测量值的1.75 - 2倍。这一结果表明，海洋混合层比相同应力驱动的剪切驱动湍流边界层更有活力。本文利用2000年秋季北太平洋两个拉格朗日浮标72个浮标日的混合层垂直速度观测资料对上述结果进行了验证。这些浮子比D 'Asaro以前使用的浮子更中性，从而减少了可能的偏差。风应力估计从快速散射仪卫星测量，因此受到的错误和偏见不同，在D 'Asaro的以前的工作。尽管这些仪器的差异，新的结果是非常相似的，以前的工作，除了不需要修正的内部波速。^w 2的值
D’Asaro, in previous work using nearly neutrally buoyant Lagrangian floats in a wind forced mixed layer, found ^w2 &5 , where ^w2& is the mean square vertical velocity and u * is the friction velocity estimated 2 Au * from shipboard meteorological measurements using bulk formulas. Depth profiles of A(z) 5^ w 2 &(z)/ within 2 u * the mixed layer showed a maximum value of A(z) of about 2, which is 1.75‐2 times that measured in solidwall turbulent boundary layers driven by a wall stress alone. This result implied that the ocean mixed layer was more energetic than shear-driven turbulent boundary layers driven by the same stress. Here these results are verified using observations of vertical velocity in the mixed layer from 72 float days of data from two Lagrangian floats in the North Pacific Ocean in the autumn of 2000. These floats were more neutrally buoyant than those used previously by D’Asaro, thus reducing possible biases. Wind stress was estimated from Quick Scatterometer satellite measurements and is thus subject to errors and biases different from those in D’Asaro’s previous work. Despite these instrumental differences, the new results are very similar to those of the previous work, except that no corrections for internal wave velocities are needed. The values of ^w 2