Plass G N, Humphreys T J, Kattawar G W
Appl Opt. 1978 May 1;17(9):1432-46. doi: 10.1364/AO.17.001432.
The color of the ocean is calculated from a model that realistically takes into account the various types of scattering and absorption events that occur in both the atmosphere and ocean. Solar photons are followed through the atmosphere and into the ocean by a Monte Carlo technique. The reflection and refraction at the ocean surface are included in the calculation. The upward and downward flux is calculated at several different heights in the atmosphere, at thirteen different wavelengths from 0.4 mum to 0.7 mum. These results are compared with two approximate theories: (1) one-dimensional; (2) single scattering. The first of these theories gives results which are accurate within 10% in most cases and are easy to calculate. The chromaticity coordinates as well as the dominant wavelength and purity of the color are calculated from the Monte Carlo results for the variation of upward flux with wavelength. The ocean color near the horizon is almost entirely determined by the color of the sky reflected by the ocean surface. The upwelling light from the ocean can be observed near the nadir if precautions are taken to exclude as much light as possible reflected from the ocean surface. The color of this upwelling light from the ocean contains much information about the hydrosol, chlorophyll, and yellow substance amounts in the ocean water. The model calculations show how the ocean color changes from a deep blue of high purity for relatively pure water to a greenish blue and then to green of low purity as the cholorphyll and yellow substance amounts increase. Further increases in these substances cause the color to change to yellow green of a higher purity. A large increase in the hydrosol amount usually causes a marked decrease in the purity of the color.
海洋的颜色是通过一个模型计算得出的，该模型切实考虑了大气和海洋中发生的各种散射和吸收事件。利用蒙特卡罗技术追踪太阳光子在大气中并进入海洋的过程。计算中包括了海洋表面的反射和折射。在大气中的几个不同高度，计算了从0.4微米到0.7微米的13个不同波长下的向上和向下通量。将这些结果与两种近似理论进行了比较：（1）一维理论；（2）单次散射理论。这些理论中的第一种在大多数情况下给出的结果准确在10%以内，并且易于计算。根据向上通量随波长变化的蒙特卡罗结果，计算了色度坐标以及颜色的主波长和纯度。地平线附近的海洋颜色几乎完全由海洋表面反射的天空颜色决定。如果采取措施尽可能排除从海洋表面反射的光，那么在天底附近可以观测到来自海洋的向上光。这种来自海洋的向上光的颜色包含了有关海水中水溶胶、叶绿素和黄色物质含量的大量信息。模型计算表明，随着叶绿素和黄色物质含量的增加，海洋颜色如何从相对纯净的水的高纯度深蓝色变为蓝绿色，然后变为低纯度绿色。这些物质的进一步增加会使颜色变为更高纯度的黄绿色。水溶胶含量的大幅增加通常会导致颜色纯度显著降低。
