The methane emission from soil to the atmosphere is mostly through rice plants, only small amounts of methane is released across the water-air interface via bobbles or molecular diffusion.

Oil gas diffusion can probably occur from the product pipeline due to some factors such as pipe corrosion, foreign power collision, oil stolen by drilling hole or water hammer.

At the same time, it also shows that the diffusion from cooling water is affected by both of tidal current and heat flux.