Surface and atmospheric temperature appears to have been roughly constant for about the past twelve years, perhaps a little longer, a pattern not predicted by the IPCC models. One response has been that the "missing heat" is going into the ocean. This raises a number of questions, but I want to start with one that only occurred to me recently. Data on the surface and atmosphere is routinely reported in the form of average temperature. Data on the ocean is routinely reported in the form of total heat content. Why?
What is measured, in both cases, is temperature. Presumably the heat content numbers are produced either by multiplying average temperature by the heat capacity of the ocean or perhaps by doing it for different parts of the oceans and adding. To reverse the process, one divides the increase in heat content of the ocean by the heat capacity of the ocean. The result should be the increase in average ocean temperature. I have not been able to find any exact statement of what the heat capacity of the oceans, so calculated it, using the following figures found online:
Heat capacity of ocean water:
Volume of the oceans:
billion cubic kilometers
A cubic kilometer is 10^9 cubic meters and a cubic meter of water is 10^3 kg. Multiplying it out, I get a heat capacity of the ocean of about 5x10^24 Joules/°K. Readers are invited to check the calculation.
Consider the following graph:
It shows an increase in ocean heat content from 1960 to the present of a little less than 2x10^23 Joules. Dividing that by the heat capacity of the ocean gives us an increase in average ocean temperature over fifty years of .04°C. That looks a lot less scary than the graph of heat content, which may explain why it is not the form in which the data is usually presented.
And it matters. Assuming the IPCC calculations of net heat content increase are correct, the effect of heat going into places other than the ocean is significant. The effect of heat going into the ocean is not.