Green's law

In fluid dynamics, Green's law describes the evolution of non-breaking surface gravity waves propagating in shallow water of gradually varying depth and width. The law is named after George Green. In its simplest form, for wavefronts and depth contours parallel to each other (and the coast), it states:

where ${\displaystyle H_{1}}$ and ${\displaystyle H_{2}}$ are the wave heights at two different locations – 1 and 2 respectively – where the wave passes, and ${\displaystyle h_{1}}$ and ${\displaystyle h_{2}}$ are the mean water depths at the same two locations.

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