It looks to me as if your calculation
But when people worry about AGW it usually isn't primarily ocean temperatures they're worried about, it's land temperatures where people live and grow crops, and the mechanism they worry about isn't that human activities make the oceans hotter and everything else follows along, it's that human activities warm the atmosphere which changes human comfort and crop yields and so forth.
So, assuming the consensus view on AGW generally, what your calculation suggests is that we should expect to see the atmosphere warming faster than the oceans. (That might have interesting consequences for things like winds but I don't know enough about this stuff for my guesses to be worth much.)
Let's not debate the larger AGW question, just the specific one about ocean temperature. Based on the estimated rate of ocean heat accumulation taken from the graph, as well as my calculation about the heat capacity of the ocean, it appears that we will get 1 degree of ocean warming in 500 years. True or false? If false, what's wrong with the calculation?
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
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