Your ocean appears to jitter or chatter along its horizon. If this occurs, you can smooth or filter the flickering pixels along your ocean’s horizon.

To filter your ocean along its horizon

1. In the scene view, select the ocean that appears to jitter along its horizon.
2. In the Attribute Editor, select the oceanShader tab.
3. In the Ocean Attributes section, increase Horizon Filter and then test render your ocean’s simulation. Repeat this step until the jittering along your ocean’s horizon disappears. See Horizon Filter.