Observations of ocean temperatures have revealed that the ocean heat content has been increasing over recent decades.
The ocean "skin layer"is the very thin – up to 1 mm – layer at the top of ocean that is in direct contact with the atmosphere.
Absorption of the infrared emissions from atmospheric greenhouse gases reduces the gradient through the skin layer.
As a result, the flow of heat from the ocean beneath the skin layer will be reduced, leaving more of the heat in the top few meters of the ocean water, increasing water temperature.
In a stable climate the net heat into the ocean would be zero. Generally, there is cooling at high latitudes, warming in the tropics, but the heating would match the cooling. and the ocean heat content would be roughly stable.
There are short term disruptions to that stability from ENSO (El Nino and La Nina cycles that redistribute heat to and from the surface of the Pacific Ocean). Over a long period, such as 30 years, those cycles will offset each other
Greenhouse gases and clouds reduce the difference between the ocean surface temperature and the bulk temperature in the few meters below the surface, which reduces the rate at which this area would be cooling.
That's comparable to greenhouse gases in the atmosphere, which reduce Earth's ability to cool itself.
The ocean surface is on average warmer than the overlying air, because the ocean absorbs a lot of heat from the sun.