"Oceans have about 200 times the mass of the atmosphere."
Not quite.
From Bob Carter's Climate: the Counter Consensus
The heat capacity of the ocean The ocean covers more than 70 per cent of the Earth's surface, and over much of its area it is 3-5 km deep. Comprising water, which is one thousand times denser than air, the ocean has far more mass than the atmosphere (1.5 x 1018 tonnes compared to 5 x 1015 tonnes) - notwithstanding that the atmosphere covers the entire planet and is 50 km high to the top of the stratosphere. The result of this is that the ocean has a much greater heat capacity than the atmosphere, specifically 3,300 times more. Put another way, all the heat energy contained in the atmosphere is matched by the heat content of only the upper 3.2 metres (m) of the worldwide ocean.
