The Structure of Light Radiance in the Depth of the Sea for the Problems of Horizonal Visibility of Submerged Objects

The spatial and angular structure of light radiance in the depth of sea water can be precisely computed with such numerical programs as Hydrolight. Unfortunately, such calculations demand a lot of computational time if used for problems of visibility of submerged objects. In this case, due to the much greater computational efficiency and logarithmic dependence of visibility parameters on radiance values, analytical radiative transfer methods are preferable. In this presentation, a new analytical radiative transfer method is proposed to solve visibility problems in sea water. The angular structure of depth-dependent light radiance in the sea is obtained in the framework of previously published self-consistent approximation. The analytical expressions proposed in this paper allow one to compute a horizontal visibility of submerged objects. This approach can be applied to problems of diver visibility in shallow water bodies of arbitrary turbidity and illumination. Presented at the Conference on Remote Sensing and Modeling of Ecosystems for Sustainability held in Denver, CO on 2-4 Aug 2004. Published in Proceedings of SPIE, v5544, p372-379. Sponsored through program number VSF-73-6641-04-5.