What effect does spreading oil on the open sea have?

Spreading oil on the open sea primarily affects the water's surface by creating a thin film that can disrupt the formation and behavior of waves. When oil covers the surface, it reduces the surface tension of the water and creates a barrier that prevents the wave crests from breaking as they normally would. This is because the oil dampens the energy transfer that occurs between the air and water, leading to a calmer surface.

In addition, the presence of oil can significantly alter the marine environment, impacting how waves behave and potentially influencing currents. The other effects related to ocean oil spills include potential harm to marine life and ecosystems, but the specific impact on wave dynamics is best described through the influence of oil on wave crests not breaking.