深水波浪破碎与气体交换速率之间的关系

表面更新理论给出气体交换速率k与海面附近的海水湍动能耗散率呈1/4次方关系,而波浪能量耗散率Dt与湍动能耗散率密切相关。本文利用两种海浪谱耗散模型——Hasselmann模型和Phillips模型,结合深水浮标海浪频谱的观测数据计算了波浪能量耗散率。以前人给出的k与海面上10m高度处的风速U10关系式的平均值为标准,采用最小二乘的方法得到了k与Dt的经验关系。在此基础上,进一步利用SWAN和WAVEWATCHIII海浪数值模式计算了理想深水情况下的波浪能量耗散率,探讨了由海浪模式计算的波浪能量耗散率与气体交换速率之间的关系。结果表明,与SWAN模式相比,WAVEWATCHIII海浪数值模式结果与实际观测更为接近。

RELATIONSHIP BETWEEN BREAKING WAVES AND GAS TRANSFER VELOCITY IN DEEP WATER

We studied the relation between gas transfer velocity k and the wave energy dissipation rate D_t in deep ocean, by dimensional analysis using turbulent kinetic energy dissipation. We obtained D_t with observational spectral data of the Hasselmann and Phillips models. Based on the average of the available relations between k and wind speeds at 10m, we derived the relation between k and D_t using the least-square fitting. Furthermore, we adapted the SWAN (Simulation Waves Nearshore) and WWATCH (WAVEWATCHIII) models in deep-water experiments under ideal conditions to derive the relation between the model-simulated D_t and k. The results show that the WAVEWATCHIII simulation is more consistent with the observations than that of the SWAN modeling.