Photo: One claim I have repeatedly seen in online arguments about global warming is that it has not really paused, because the "missing heat" has gone into the ocean. Before asking whether that claim is true, it is worth first asking how anyone could know it is true. A simple calculation suggests that the answer is one couldn't. As follows ... .

Part of the claim, which I assume is true, is that from 90% to 95% of global heat goes into the ocean, which implies that the heat capacity of the ocean is 10 to 20 times that of the rest of the system. If so, and if the pause in surface and atmosphere temperatures was due to heat for some reason going into the ocean instead, that should have warmed the ocean by 1/10 to 1/20th of the amount by which the rest of the system didn't warm.

The global temperature trend in the IPCC projections is about .03°C/year. If surface and atmospheric temperature has been flat for 17 years, that would put it about .5° below trend. If the explanation is the heat going into the ocean, the average temperature of the ocean should have risen as a result above its trend by between .025° and .05°.

Would anyone like to claim that we have data on ocean temperature accurate enough to show a change that small? If not, then the claim is at this point not an observed fact, which is how it is routinely reported, but a conjecture, a way of explaining away the failure of past models to correctly predict current data.

The next question is what has actually happened to heat content. The data are shown at

http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/.

If you go to the page it insists on showing you a series of different graphs, so I am pasting in a screenshot of the first one to supplement the URL: The second shows heat content down to 2000 meters--you are welcome to look at that and see if you agree with me that it shows the same pattern, if a little less clearly.

Examining the graph, in particular the black line which shows the yearly average, it looks as though the rate of increase from about 2003 on is slower, not faster, than over the previous decade. The change isn't as striking as the corresponding change in the graphs of surface or atmospheric temperature and it seems to start a little later, but it is just the opposite of what we would expect if the slower warming elsewhere was being balanced by faster warming of the ocean. And, since the ocean is being heated from above, one would expect the pattern of ocean temperature to lag the pattern of atmospheric temperature.

Anyone interested in disputing either half of this post and defending the claim that there hasn't really been a slowdown in global warming because the missing heat went into the ocean? I'm not looking for links to articles claiming that it's true--too much of the online argument on climate consists of dueling appeals to authority. I'm looking for actual arguments.
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David Friedman
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One claim I have repeatedly seen in online arguments about global warming is that it has not really paused, because the "missing heat" has gone into the ocean. Before asking whether that claim is true, it is worth first asking how anyone could know it is true. A simple calculation suggests that the answer is one couldn't. As follows ... .

Part of the claim, which I assume is true, is that from 90% to 95% of global heat goes into the ocean, which implies that the heat capacity of the ocean is 10 to 20 times that of the rest of the system. If so, and if the pause in surface and atmosphere temperatures was due to heat for some reason going into the ocean instead, that should have warmed the ocean by 1/10 to 1/20th of the amount by which the rest of the system didn't warm.

The global temperature trend in the IPCC projections is about .03°C/year. If surface and atmospheric temperature has been flat for 17 years, that would put it about .5° below trend. If the explanation is the heat going into the ocean, the average temperature of the ocean should have risen as a result above its trend by between .025° and .05°.

Would anyone like to claim that we have data on ocean temperature accurate enough to show a change that small? If not, then the claim is at this point not an observed fact, which is how it is routinely reported, but a conjecture, a way of explaining away the failure of past models to correctly predict current data.

The next question is what has actually happened to heat content. The data are shown at

http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/.

If you go to the page it insists on showing you a series of different graphs, so I am pasting in a screenshot of the first one to supplement the URL: The second shows heat content down to 2000 meters--you are welcome to look at that and see if you agree with me that it shows the same pattern, if a little less clearly.

Examining the graph, in particular the black line which shows the yearly average, it looks as though the rate of increase from about 2003 on is slower, not faster, than over the previous decade. The change isn't as striking as the corresponding change in the graphs of surface or atmospheric temperature and it seems to start a little later, but it is just the opposite of what we would expect if the slower warming elsewhere was being balanced by faster warming of the ocean. And, since the ocean is being heated from above, one would expect the pattern of ocean temperature to lag the pattern of atmospheric temperature.

Anyone interested in disputing either half of this post and defending the claim that there hasn't really been a slowdown in global warming because the missing heat went into the ocean? I'm not looking for links to articles claiming that it's true--too much of the online argument on climate consists of dueling appeals to authority. I'm looking for actual arguments.

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