海浪(以及地中海类型海洋和较大的湖泊,但规模较小)是由两个过程:生成——本地生成波(“浪风”),跟着风的方向;——波生成进一步在大海(即。膨胀波),它不一定跟着风的方向。在夜间,你可能看到膨胀波。当然,一些波能量也产生相反方向的离岸风,但我们只能“看见”这些波进一步在海里如果风足够强大的定义(见[取回](https://www.britannica.com/science/fetch))。也检查下面的图\[1 \]的澄清如何生成膨胀(时间越长周期波能量传播速度比短的能量波,所以最初的“随机”波场分解成普通膨胀)。[![在这里输入图像描述][1]][1]浅水波过程衍射和折射曲线波的路径会到达海岸,“感觉”。海浪似乎标题几乎垂直到达海岸时,即使1公里出海他们几乎平行于长距离海岸移动。波出现在海岸观察者如何取决于当地风的方向。 Generally, if the local wind blows in the same direction as the waves (i.e. onshore wind), the waves appear "mushy" as the wind helps to break the waves (see example [image](https://kimasurf.com/blog/wp-content/uploads/2015/01/23012015.jpg)). If the local wind blows in the opposite direction of the incoming waves (i.e. offshore wind), the waves maintain their shape due to opposing wind and they break later (see example [image](https://live.staticflickr.com/3176/3072941457_33c55c22a1_b.jpg)). These conditions are favourable to surfers. \[1\] Holthuijsen, L. H. Waves in oceanic and coastal waters. Cambridge University press, 2010. [1]: https://i.stack.imgur.com/ZFiiQ.png