用 Monte Carlo方法数值模拟海浪 ,研究其波包曲线跨某参考水平的波包中空波包所占的平均比例 ,并与 Ditlevsen和 L indgren关于空波包的理论相比较。结果表明 ,在二阶近似下该理论近似适用于海浪。在此基础上对 Longuet- Higgins的群性波包理论进行修正。修正后的理论与数值结果的比较表明本文所做的修正是十分有效的。修正后的群性波包理论克服了原理论的某些固有缺陷 The Monte Carlo method is used to numerically simulate ocean waves and to study the average proportion of wave packets whose wave packet traverses a certain reference level and to compare with the Ditlevsen and L indgren’s theory of air-wave packets. The results show that this theory approximates sea waves in the second-order approximation. On this basis, the theory of the wave packet of Longuet-Higgins is modified. The comparison between the revised theory and numerical results shows that the correction made in this paper is very effective. The modified theory of group wave solves some of the inherent flaws of the original theory