耦合模式中海浪参数对台风浪预报的影响研究

以西北太平洋一次"双台风"共同影响下的台风浪为例,针对模式中风摄入和白帽耗散、底摩擦、波破碎、波-波非线性相互作用等海浪物理过程对台风浪预报的影响进行了敏感性试验分析。在此基础上,基于各物理过程最优参数化方案探讨了耦合模式和单独海浪模式的海浪预报性能,分析了耦合模式的海浪预报场分布特征。结果表明:不同海浪物理过程参数化对于波高预报的准确性是有所差异的。在相对最优的海浪各参数化方案组合下,无论耦合模式还是单独海浪模式都能较好地反映波高的变化和分布趋势。相比而言,耦合模式对于台风浪大值区的浪高预报要比单独海浪模式的更接近观测,且可以很好地刻画出双台风影响下浪的分布演变特征,对于西太平洋台风浪的预报具有很好的适用性。

A study on the influence of wave parameterizations in coupled model on typhoon wave forecasting

Based on the simulation of binary typhoons over the northwestern Pacific Ocean,a serie of sensitivity experiments are conducted to study the parametric effects of wave physical processes on typhoon wave forecast,such as wind energy input,white capping,bottom friction,depth-induced wave breaking,and nonlinear wave interactions.We also discuss the forecast skill of coupled model and individual wave model based on optimal parameterization scheme of each process,and analyze the characteristics of ocean wave in coupled model.It is shown that the accuracy of wave height forecast varies among the parameterization of different wave physical processes.Both coupled model and individual wave model can reasonably depict the wave height variation and distribution under a combination of the relatively optimal wave parameterization schemes.It is found that the coupled mode can better characterize the distribution and evolution of binary typhoon wave,and predict the wave height with more accuracy over the high wave areas of binary typhoons compared to individual wave model.The study demonstrates good applicability of coupled model in forecasting typhoon wave over the northwestern Pacific Ocean.